Prepress Technology for magazines and newspapers - 1994

Proceedings of the IPP Prepress Conference

The second day of the conference took up for consideration output devices. An overview of present and future technologies was provided by Pranav Parikh of TechNova, Bombay. The users’ considerations in evaluating output devices were presented by Purnendu Sen of The Times of India, Bombay. His presentation also included a brief discussion of the IFRA document on frequency modulated screening. Then, Kek Hwa Choon of Scitex Asia-Pacific, Singapore, presented Scitex’s outlook on the future. This was followed by a marathon performance by Pranav Parikh and Purnendu Sen on the Standard Specifications for Offset Printing. The final session of the conference was a panel discussion in which all the presenters were joined by Naresh Nath of Delhi Press and George Jacob of Malayala Manorama. The panel discussed magazine systems, used prepress equipment, and training issues for the industry.

The path forward for digital prepress: the highway versus the bylanes

PRANAV RANAV PARIKH, OF TECHNOVA, BOMBAY, MADE the first presentation of the day which was an over- view of computerized prepress and output devices, “Is your vision of the path fraught with paralysis and confu- sion in the face of multiple options and opportunities? Or do you see yourself chasing your tail trying to decide which vendors will give you the cheapest system and then trying to decide whether that system will do what you want it do? Or do you see yourself trying things out by trial and error and essentially moving around in a circle? Or do you see yourself knowing the path forward, having a clear concept of it and waiting for a breakthrough but not getting support for going ahead from the top man- agement?

“The best way to see the path forward is to see it is as a highway between information and the printed page: thei way or the imaging highway. This is the path forward for imaging solutions which will keep you on the high- way and not in the bylanes where you have a mix and match of solutions that don’t really work. If you stick to the highway, the fastest route from point A to point B, you can knock off a lot of solutions and avoid a lot of pain. Various CTP routes: “The first landmark consists of closed loop prehistoric working systems which are proprietary but have no future and are of only historic significance. These provide text galleys only, suitable for pasteup. The next historical stage may be described as a computer to where the editorial front end has been moved to standard computer platforms but where the back end is still proprietary and produces text only galleys for pasteup. Computer to page positive is the next landmark where you end up with full pages including text, illustrations and photographic images. Computer to plate is one of the newer technologies that bypasses the film stage and outputs directly to lithographic plates. Many types of small offset plates are also available including those using a polyester base. On offset printing machines such as the GTO-DI, fresh plates are imaged directly on the press. There is computer to press, digital printing, such as the Indigo and Agfa Zeikon which are colour oriented devices. Inkjet printing is used for personalized and customised products where every piece, even at high speeds on a web offset machine has a different piece of information on it.

Large format imagesetters and platesetters: “Although large format page imposition imagesetters and computer to plate are very exciting because you eliminate all the films, these are being tested at beta sites and may not yet be appropriate for the Indian market. An auto magazine has just been printed without any films, the world’s first colour magazine to be digitally produced. Even the ads which were received on film have been again put into a digital form for output to plate.

“Computer to plate does not yet lead to savings by avoiding the cost of film. The new kind of plate is more expensive than the cost of film and conventional  presensitized plates. The real advantage of this technology is flexibility of the workflow and ability to cope with last minute changes. Imposition can be changed on the fly Bat if you need to make two or three sets of plates you are still better off going the film route. “We are already negotiating with two large newspapers to supply full computer to plate systems using silver sensitized plates.

“Although there are approaches such as electrostatic plates and organic photoconductive plates, there is a strong trend in favor of silver based plates since they resemble film and also can be exposed on imagesetters with appropriate upgrades CCD flatbed scanners. “CCD flatbed scanners are cost effective. They are much cheaper than PMT drum scanners for the same quality level. The density range can go up to 3 and you don’t need much more than that. Scanning resolutions are over 5000 DPI and you don’t need more than that for 15 times enlargement at 150 line screens. The image depth available is 12 bits per colour and you don’t need more than 8 bits per colour. These scanners give much higher throughput with up to ten scans per hour and all kinds of originals including thick flat reflective originals can be scanned.

“In terms of speed, volume, and quality, one should define requirements into one of three segments. The maximum speed and quality would define high end co- lour on coated stock or what could be described as commercial level prepress. Midrange quality, midrange vol- ume could define ROP colour on newsprint. Entry level may be defined as black and white, low volumes with text and 85 DPI halftones. If possible, one should define where you need to be in the next five years and how to get there step by step without throwing anything away.

“A beginning configuration could be a PC linked to an 1800 DPI laser printer that outputs 12 inches by 19 inches with crop marks. This can also send data to your proprietary system for film or bromide output or to an older editorial system. Some of the older imagesetters could also be enhanced with newer software RIPS.

“Gearing up to the next level could be full PostScript for black and white text and graphics PCs could be connected to your editorial network, you may have a server, a low cost scanner, connect your 1800 DPI laser printer which is still useful for most of your work and for higher level output such as halftones you could go in for an entry level imagesetter.

“Further upgradation could take you up to full PostScript. In the same configuration you may want to upgrade the RIP which, if it is a software RIP, would be easy. A colour desktop scanner would be useful. Various cap- stan imagesetters have entry level colour options. And you could use an inkjet colour option for proofing. This makes an entry level colour configuration.

“Mid range PostScript colour would simply add a mid- range scanner instead of an entry level scanner. You can add a Mac with Photoshop and could upgrade to the highest level of colour capable capstan imagesetters. Midrange high speed colour for higher volumes. Your Mac may now work with higher level software. You could get a Scitex $40 L. scanner. Proofing may have to be up- graded to something like high end inkjet such as the Iris and the imagesetter should be an internal drum and not just a capstan. The entire configuration would be capable of taking in and outputting in PostScript format. And every workstation would have this flexibility.

“The top end configuration would include high end colour and computer to plate. If you were upgrading you would simply add on storage devices and a direct com- puter to plate imagesetter. This would eliminate the films from your workflow completely.

Imagesetter speeds and spot sizes

“A quick idea of the speed of the capstan imagesetters in the market today: The range is around 8 inches per minute to 22 inches per minute at 1200 DPI. If one compares that with the price chart, the relationship is not simply one to one and don’t go on price alone.

“One of the most important considerations is the spot size which is related to addressability. We generally mix up resolution and addressability. Addressability is the number of dots that an imagesetter can put in a linear inch. So if you are talking about an addressability of 2540 you are talking about 2540 spots possible in a linear inch. If you have an 10 micron spot size then with 2540 addressability you are actually putting down spots without any overlap at all. This is zero overlap or one divided by the addressability. What is therefore the optimum spot size that one should have? There should be some overlap and it should be less than two divided by the addressability; roughly some- thing like a 25 per cent to 50 percent overlap. If the spot is too small or if there isn’t any overlap you may get streaks in the dark tint areas. The solids won’t be solid. If the spot size is too large, there will be a loss of tonal gradation in highlights and shadows. A one percent dot at 150 LPI is equal to a 20 micron size. Also keep in mind what is the finest line that you need to have; a 10 micron spot is equal to three hundredths of a point.

“Thus you would look to compare maximum output width, laser type, spot size, repeatability, and resolution related to screen rulings. There are many intangibles, such as the shape of the dot, durability, support in the field, and the component changeability in the field. How- ever the most important factor for evaluation is the out- put on film.”

Sunil Khullar from Digital Studio in Bombay, com- mented: “We have missed out another important component of newspapers: advertisements. In the next five years we still cannot expect to get digital media from ad agencies.”

Pranav Parikh, in response, commented, “There is no problem in scanning in separation films using scanners such as CCD flatbed scanners and so you don’t have to sacrifice full digital output. On the question of dot gain and loss in this process, a lot of work has been done by us for a large newspaper in the South without any loss or gain in dot area or grey balance or moire patterns. The project is not yet complete, however.”

Naresh Khanna, putting in his two cents worth, added, “In what may be a partial answer to Sunil’s query on advertisements, Misomex has come out with a hybrid platesetter that can output from a combination of digi- tally imposed pages and film pages. With the recent international tie-ups of advertising agencies, we can expect a lot of advertising to be available to us digitally but the local agencies, publishers, and repro houses are not yet really able to absorb or output this data.”

Satya Mohapatra of Ananda Bazaar asked a question about various screening approaches, about rational and irrational screening and for comments on whether an open rosette or closed rosette would be most appropriate for newspaper printing.

Pranav Parikh responded, you have to finger- print your to the profile of your capa- bilities under different conditions, the paper ink combi- nations, blankets, plates, the fountain solutions. Once you determine these, you can experiment with all kinds of screen rulings. It’s a misnomer to think that higher screen rulings will give better reproduction. It’s also a misno- mer to think that an elliptical dot will have less dot gain than a square dot, nor can round dot screens be ruled out. Even the high end auto magazine that was produced entirely direct to plate had to deal with many advertisements that had been supplied on film. The other issue here is colour management. You may get a digital proof and you may get a file but unless you have colour specs which you can use for communication, these still won’t serve the purpose. We are still at the SSOP stage in India with maybe five different shades of magenta, ten differ- ent shades of cyan and we don’t seem to be ready to talk about colour management at this stage.”

Mr Shankaran from Monotype also pointed out that in the high end prepress configurations it would be necessary to use a OPI server to avoid the bottleneck of large image data files having to move around the network.

As far as dot gain, Pranav Parikh added, “You will obviously have a larger dot gain on a toner based ma- chine than on an imagesetter. However, the trade-off is that on a film, a polyester based film with special coating and which is designed to restrict the dot gain you can control the dot gain. On an imagesetter you always have problems with the laser intensity and with the develop- ment process. If the developer is not properly controlled you will always have problems with dot gain. On a laser printer we found that the same image exposed on a 1800 DPI laser printer there was negligible dot gain. Also there was no problem with density and polyester base is the same as that of film.” Purnendu Sen to some extent re- futed this argument later on in his presentation.

Registration. Arun Shankar of Data Quest, said that, “Our experience with PostScript colour and capstan imageset- ters is that apart from the problems of outputting time and moire, there were problems in registration.”

Pranav Parikh replied, “For commercial quality colour you need internal drum imagesetters. But for mid range colour there are colour capable capstan imagesetters. You actually need to take a test. I to 1.5 mill is a good range as far as repeatability.”

Selecting output devices, a user’s view

HE NEXT PRESENTATION WAS BY PURNENDU SEN, Times of India, Bombay. “First, as a user if I had to select an imagesetter, how would I do it? I will talk about some specs and some related issues. One cannot talk about imagesetters without talking about RIPS and the selec- tion of RIPS. As far as all the technologies and options we have been hearing about for the last one and a half days, according to me, the manufacturers are not fools to invest thousands and millions of dollars in research. Every product has a place or a purpose or a justification but we must choose the right one or the right combination for our- selves.

RIP developments, PostScript Level 2. FM Screening. “There are several types of output engines but really speak ing as far as conventional specifications we must look at: machine type, the measure (width), resolution, speed, laser source, repeatability, spot size, optic system, film transport, exposure, space and power requirement, com- munication interface, screen technology, the RIP, and the price.

“Suppose you are buying a laser printer: You need to establish the requirement. Is it for my personal printer? Is it for a workgroup or a single activity department? Or is it for an entire department? If you need from 3,000 to 8,000 pages per month, or 10,000 to 20,000. Even tab- loid size laser printers of 200,000 outputs per month capacity are available. It is necessary to first establish the output requirement

“Normally people keep on talking about RIP speed without taking into consideration what kind of graphics and without differentiating between simple and complex graphics. RIP speed and engine speed have to be looked at separately. In certain situations even a slightly slower RIP with a fast engine may suffice.

“Network interface, Local Talk, Ethernet, the communication interfaces have to be looked at. As well as resolution. And what kind of paper handling and additional emulations does the output device have?

“IFRA, based in Germany, has done various studies and we have used the IFRA output test form for testing laser printers and imagesetters. We have used it for evaluating output engines including the Linotronic 300, Q and R imagesetters and laser printers. We have found the staircase effect (jaggies) to exist both on laser printers and imagesetters “We are normally defining density in lines per inch or dots per inch. Generally, the lower the density, the lower rendering quality of the device. The IFRA test form is available in a floppy which contains a step wedge, type in large and small sizes, negative, positive, halftones in 20% and 40% and a continuous tone step wedge. This test form on a floppy costs a few hundred DM. Output it on any device and print the result on the press. Why talk? Printing is a science. I would say please use this when you are making a buying decision of this magnitude. We have done this and I can report our observations. With type, at low resolution you have a blurring effect around type which doesn’t disappear on web offset presses. Even on photographic paper this effect is there. Of course at higher resolutions on a photographic paper it is much less. In our case it is more because we use facsimile transmission. If you are using a direct copy camera it is much less.

“We validated or cross checked an IFRA study on do gain on our GOSS Metroliner. Look what happens to your 50% dot; it goes to 72-73 %. But look at what is happening in the highlight area and this is critical for colour reproduction. The dot gain is nearly 17 to 22%. However, the final print dot gain reduced to 10%. It is accepted in offset printing anything within 20% in the midtone is okay and we follow this. We achieve this sim- ply by following the manufacturer’s instructions.

“There is always a difference between a photographic process and something which has a dye. Photographic output is a chemical deduction process, it is not an additive process. Anything that you add has its own surface tension and the surface to which you apply it also has its own surface tension. Therefore, any dye that you are depositing will spread no matter what you do, whether you take it on paper or film where it may be less. But in chemical deduction it may be only .5 or 1%.

“When you are deciding on an output engine you can- not overlook the front end system and the management system. Front end, communication, and graphic handling capabilities. How good is your resource management in the whole system? The difference between vendors is often the detailed work that they do in the communication within the environment.

RIP evaluation. “For one of our language papers with a PC system running an old imagesetter we needed to up- grade the RIP. We short-listed two RIPs and requested a day’s production trial. I did not believe the Seybold Report and the only reports that I believe in are the IFRA reports. I don’t allow any computer engineer to come and give me a lecture. So we tested the RIP in our envi- ronment with six typical jobs called job one to job six.

“We ran the test suite of six jobs on this system which contained a PC based editorial system, a file server, a device server with a Centronics interface to a Linotype RIP 2, which is a hardware RIP, and on to the Linotronic 300.

“We found that the bromide consumption is constant at 24 units and imaging time was constant. The new RIP ran on a 486 with 64 MB. We noted all the times in the existing situation and then using the new RIP. We found that with the new RIP nothing happened. It turned out that our old front end was supposed to be PostScript but it was routed from the file server to the device server and only then to the RIP by the supplier for security reasons. This was not a problem of the new RIP but of our old front end software and I am dwelling on this simply to highlight that we need to know what we have and that we cannot take this concept of PostScript too much for granted.

“After the Hyphen engineer wrote a small software program, however, the configuration did work. We discovered that 50% percent of our time was spent in file transfer and 40% was the imaging time and only 10% of the time was spent in RIPPING. We then moved the files to the file server and directly connected the Hyphen and the Harlequin RIP and rechecked the times with a stop- watch. And then we looked at other features such as whether the RIP works on the parallel mode which means that while one job is being imaged a second job can be ripped. We also looked for features such as film saving mode and bitmap storage facilities, preview modes etc. etc.

“However, since our testing in the last two months, newer versions have been released. For your informa- tion, your application software generates a PostScript file. And what RIPs do is to interpret and render these files on a particular device. The new Hyphen RIPware 2 has divided interpretation into objects numbered zero to n and they have separated the bit mapping and image set- ting. Multiple processing reduces your ripping time. While normal processing means a linear handling of objects, parallel job handling, allows a somewhat random access to the separate and numbered objects. Other new RIP features include: the imposition of various types of pages, vector objects, multiple processors, buffer storage, and a driver manager to prioritise and manage the various combinations of multiple rips to multiple imagesetters. Also incorporated are various compression algorithms from JPEG to fractal. These are also known as G list processors.

“PostScript Level 2 is also meant to take care of irregu- larities in the line widths, provide space for composite fonts with larger character sets, which will be especially useful for non-Roman language sets. Level 2 also pro- vides better screening and data compression algorithms.

FM screening. “The IFRA report has done nothing but taken away some biases that we have had in newspaper printing. In conventional halftone screening we keep vary- ing the dot size. The two related parameters are the lines per inch and the dot size. In Frequency Modulated screen- ing, the size of the dot does not vary but the number of dots increases or reduces according to the gradation.

“In gravure there are three technologies: the first is conventional gravure, where the dot size remains the same and cell depth varies. The second is where cell depth remains the same and the dot size varies, and in the third the depth remains the same and the dot size remains the same but only the number of dots varies. We learned this 25 years ago when I was an apprentice. And this is similar to FM screening.

“The IFRA report says that to decide on resolution we need to go first to the reader to see what the human eye can resolve. Our eyes can resolve 28 pairs of lines in a centimeter. This translates into 56 lines per centimeter. All the business of spot size and diameter and resolution starts from here. In newspapers we are conventionally using 65, 85 or 100 lines per inch screens. Why are we not using higher resolutions? The last answer is dot gain. As you go from 22 to 35 lines per centimeter the dot gain keeps on increasing. This is why newspapers come down to 28 lines per centimeter. This was also my idea until I read the IFRA report last week and now I am going to try out FM screening and print this screen on a high speed. rotary offset machine and calculate the dot gain that we get.

“It is not yet recommended to use FM screening if you are still using paste ups and copy cameras or even full page transmission. But if you are using imagesetters to output full pages including images FM screening could be tried. In frequency modulation the dot gain is really very high but we can control it to a large extent. Although the dot gain is higher this should not prevent us from going for FM screening for newspaper printing. If you can control your dot gain and you can select the appropriate spot size, FM screening will give better results be- cause with an increase in the number of dots, your gradations will be far smoother. This is why if you compare the same image on offset and gravure, will be far better. Keep in mind that the minimum gravure screen is 270 lines per inch and this is also the magic or charm of gravure. Provided we can control the dot gain, that we can select the correct spot size and that can also look after the ma- chine conditions and the other inputs we can achieve positive results in our tests. I hope to show the results of FM screening experimentation at our meeting next year.”

Sunil Khullar pointed out that, “The formulae presented by both Sen and Parikh in their talks for calculating grey levels were for PostScript Level 1 where dot shapes remain constant in position. In Level 2, and even in Hyphen’s Spectracell and Adobe’s Supercell dot shapes change and you can get much higher LPI for the same resolution. For instance if you have 1000 DPI devices, and you are looking for 100 LPI output in a conventional Level 1 PostScript you will get only 100 grey levels but on PostScript Level 2 or using Spectracell you can get up to 256 grey levels at 133 LPI. Thus the biggest advantage of Level 2 is that it gives you much higher LPI at lower resolutions.” Khullar raised a further query on dot gain, “PostScript gives you a function called transfer table which lets you compensate for dot gain. Even applications such as Photoshop and Quark allow one to compensate for dot gain. Then, why are we so bothered about dot gain? Dot gain is well documented and the measurement of dot gain is also documented. Is it really an issue?”

Sen’s response essentially pointed out that the print- ing process was a series of steps and variables where the end product is perhaps still a subjective visual compro- mise. Pranav Parikh added, “The issue is standardization and you may be able to compensate in-house for dot gain but what about separations from outside? In my view more important than resolution is the tonal gradation and the moment you compress something you are losing tonal gradation throughout the entire scale. We are talking about measuring the 40% dot only to monitor or evaluate dot gain but don’t forget the full range. Which means you have to be able to work out curves of what will pre- serve the tonal gradations while you are compensating for dot gain. Thirdly, why tolerate dot gain at all? One must fight it like cancer. If you can keep it at a fixed level day in and day out, that’s all right but if you resign your- self to high dot gain, like cancer it will change. There are periods when cancer is passive and periods when it will grow and you can do nothing about it. Thus, let us not misuse the ability to compensate for dot gain in the imagesetter.” Naresh Khanna added that, “As far as frequency modu- lated screening, the human eye is most easily deceived at a resolution of 56 lines per cm which is approximated by 150 lines per inch and this is the normal resolution that we associate with art paper, with some coffee table books going to 200 or 300 LPI nowadays. Newsprint printing and even colour printing on newsprint is at much lower resolutions. The point that the IFRA report really makes is that there are a lot of problems associated with FM screening at higher resolutions but newspaper printing is an ideal and low cost, high benefit problem to solve in regard to FM screening. As for dot gain, we are currently relying on hybrid systems and on flat bed proofs which in fact have a dot loss compared to actual production machines. So when we go to totally digital systems and proofs we may be able to more easily monitor and com- pensate for dot gain. I was recently in an installation which had three different kinds of digital proofs all indistin- guishable from the final print.”

Purnendu Sen: “I will never look at a digital proof. These are for my editors and customers who do not un- derstand the ABC of printing…. Digital proofing is like a war that I don’t want to discuss here.”

More on digital proofs. S. Mohapatra pointed out that Parikh and Sen seemed to have opposite views on digital proofing. Although Mr Sen acknowledged this as a possi- bly healthy fact, Mr Parikh attempted to clarify the issue by saying that “the objective is that firstly, proofs should be matchable on the press. And secondly, the customer requires a cheap method of seeing what he will get on the final print. A printed proof is acceptable to a printer. A flatbed proof is a compromise. So also is a Chromalin. A digital proof which does not take into account the press characteristics or does not resemble the printed product will not be acceptable. But a digital proof which calibrates the printing conditions, the ink paper combinations, the dot gain, trapping etc. has a high possibility of being acceptable to Mr. Sen. Ink jets do not generate the same dot shape and so are not generally acceptable. A new technology, just released, exposes dry materials in an imagesetter at 2400 DPI and is closer to the printed proof and will perhaps be acceptable to Mr Sen.”

Mr Sen again highlighted the very high media rates for colour advertisements with their attendant risks and tight deadlines and the erratic input materials. He accepted that the science of digital proofs may not be wrong but that a lot of standardization would have to be put into place before it could be useful.

Dots and spots. Referring back to some of Purnendu Sens’s earlier comments on spot sizes, Pranav Parikh clarified, “We must remember that a one percent dot of 150 LPI screen is equal to 10 microns in size. If you had an imagesetter which is set to 50 microns in spot size that will not produce up to 5% dot at all. Thus a large spot size brings the screen ruling down.

“Also, a spot size of 20 microns does not mean a dot size direct relationship because every dot or halftone cell is made up of several spots. So if you have 150 lines per inch and if you are looking at an addressable resolution of 750 spots per inch. Thus you are putting for a 150 LPI screen five spots for every halftone cell, every dot. And five spots in both x and y direction so you have 25 spots making every dot. 25 spots plus white gives you 26 grey levels for each dot. This is what you get if you use a 150 line screen with a 750 resolution laser printer. Superim- pose on that the spot size that you should select. Consequently the ideal imagesetter is one capable of making the smallest spot size since one can overlap the spots to make a larger spot size.”

The future as Scitex sees it based in Singapore made a presentation based on EK HWA CHOON, OF SCITEX ASIA PACIFIC, his companies increased activity in the country in the last year. “When I talk about the future I speak of what is especially relevant to Scitex and India. Scitex has many views about the future and in order to realise the future we do a lot of research and development. We have 685 engineers solely in R&D. Along the way we have acquired a few more companies, the most important or recent being a manufacturer of post production video equipment. This should signal something about our future di- rection. This year Scitex came out with a new mission statement which basically says that we will be a global partner in providing a format or information or media to other carriers in publishing or multimedia or to movie producers. We will provide our technology, our format and our expertise.

“In the last year where we have been very active in India we have been finding a great deal of variety within the country. Different regions have their own requirements. There is a latitude of technologies in such a large market. And for the last one year we have been learning,

“As a vendor we look at our existing customers. For all the customers that we have today, we must provide some product to take each of them forward. Multimedia is part of this. We have acquired a multimedia company and we are no longer restricting ourselves to ink on paper or to publishing. When we look at our customer base we also need to make them more productive and to aid them in improving quality. ISO 9000 is very popular and we are still not aware of any Indian printer who has achieved ISO 9000.

Being practical. “It is interesting to talk about new technology such as FM or high definition screening. This is a new and difficult area which we will tell you about but not really push it.

“Technologies like digital colour, such as the Indigo or the Agfa Zeikon are practically impossible to introduce in India. On the other hand in India there are thousands of printing machines and not many printers are going to move to a completely new machine or technology. We do have a product for digital scanning of colour files from media such as CD-ROMs. I am very sure that this will be a new meaningful technology for India.

“A lot has been said about open platforms although they have not really been defined. It is important to be able to share files. PostScript is still gathering more strength and hardware products have come down in price but many manufacturers are going out of business. We are expecting a shakeout of those who do not have the technology or do not have the financial strength. In fact many players have already gone.

PostScript output devices. “Imagesetters are only one of them. The RIP speeds are similar and it doesn’t really matter that much, they only get faster processors and better software. On the other hand imagesetters are get- ting faster with better and better air bearings etc., but the technology seems to be mature and it will probably be- come a volume game.

“Some of the new output devices with new green tech- nologies and media are interesting but the costs are high right now and we see demand mainly in countries where strong public opinion favours green technologies.

“Computer to plate has many approaches including flatbed and drum and imagesetters. The conventional plate exposing frame still allows a great deal of flexibility in combining variously sourced films. Direct to plate will require both a special workstation and a special imagesetter. We feel that this is not very practical in the medium term, say in the next three to five years.

“Postscript digital proofing is useful if you are looking only at the layout. The function of a digital proof is speed. For a publisher this could be useful. The good thing about digital proofing is that it can be remote. You can send a remote digital proof especially for layout over the telephone line. The integrity of digital proofing with good calibration is acceptable. This is different from the issue of remote proofing.

“Inkjet technology will be very important. Colour la- ser is still expensive but the ink jets from Epson and HP have already come down enormously in cost. The ink jet technology will get more and more advanced. There will be more advances in ink jet than in laser. The basic cost of the laser drum is very high. Iris is just one of the Scitex ink jet products. We have done a lot of work in high speed inkjet for newspapers with mainly text and spot colours and this technology is meant for 60 thousand feet per hour machines. The multiple printing head means no plates and no impact; the information comes directly from the computer and it doesn’t have to be sequential information, thus we have what we might call variable imaging on demand. The quality at present is not very good. It approximates 250 DPI. It can bring down the newspaper run with a great deal of flexibility to some- thing like 50,000. This could make a difference in a country where everyone reads more than one newspaper.

Purnendu Sen asked, “In the regional newspaper, zoning is becoming the need of the hour. Can inkjet play a role in producing regional or district wise editions?”

RN Sahni of IGAM, Delhi, clarified Sen’s question, “Can ink jet technology at rotary speeds replace a page in a small edition of a full broadsheet newspaper?”

Kek’s reply to these queries was that, “The ink jet head can be very big, even eight inches. Two heads together comprising 16 inches can be placed on top of a continu- ous paper handling web machine something like a forms press. On a continuous stream of paper with a zig zag folder you could print an entire book from page 1 to 600 without making any plates. But the best thing about ink jet is that the worse the quality of the paper, the better the printing. It is very effective on newsprint but not on coated paper. The ink jet head can be placed anywhere on the web and is also used to personalise the run or for addressing. It may of course be necessary to insert the special edition pages in a newspaper since there are some problems in mounting these heads on normal web offset machines. These ink jet technologies are not all Scitex technologies. After some initial work, Scitex acquired Iris, and recently we acquired Kodak’s ink jet technology. This technology is also moving us into multicolour signage on special material or to single page colour in large formats for paper, canvas and polyester. These inks can be both waterproof and ultraviolet proof. 

“Ink jet ink will definitely come down in cost. Of course it will have to be manufactured locally. The versatility of this technology is the key. Ink jet is not high quality so it is only for text and spot colour. 60,000 feet per hour can be achieved because of the non impact nature of the process and the fastest output is achieved reel to reel. This technology can also be used for randomizing the numbering in lottery or security printing.

Client-server architecture and connectivity. “In the com- puter industry, client server is the hottest architecture. For the graphic arts industry as well, we believe that the trend will be to go to client servers simply because of the management tools that will be provided. Also many of the process intensive tasks like writing to disks or RIP- PING can be allocated to the server.

The other issue of great concern is connectivity. Graphic arts are very differ- ent from other kinds of information processing. In bank- ing maybe there are frequent transfers of small bits of data. For our applications we may need to send a file of 40MB every half an hour. We have spent a lot of effort in the past year in developing connectivity devices. We are developing very fast and reliable transfer software between different computers and operating systems. This is a very difficult task, and since connectivity is a very big issue, we are very proud of our knowledge and expertise in this area. For instance we bought a company called Leaf. Leaf had an economically priced scanner but it took some- thing like half an hour to move their scans. So Leaf was forced to develop two cards that allowed transfer at 10 MB per second to a Mac so that a file could be moved in about 6 seconds. We are building our own connectivity between Macs and PCs and RS 6000s and our own plat- form. We call this LAN C, P top. We cannot rely on stan- dard networking from Apple or Novel. SCSI 2 is too slow. Even DDI is too slow.” And, in answer to the query, Kek replied, “Yes, we do sell our connectivity products be- cause they contain a great deal of intellectual value.”

Descreening. Kek went on to finish, “We punch and scan the four pieces of film on a Monoscan which we OEM from a Danish company and we can not only descreen the old separations but enhance the quality by doing what we call a digital scan. This was originally developed for the packaging industry which often has old films and does not want to pay for making new artwork.”

Standard Specifications for Offset Printing

HERE WERE TWO PRESENTATIONS ON THE SSOP T1989 document and it use. (The entire document was circulated with the conference papers and we have again reproduced it in this issue.) Purnendu Sen introduced Pranav Parikh’s overview, “It was felt that Bombay advertising agencies, newspapers, magazines, photographers, ink makers, paper makers, cylinder makers for packaging, and repro houses should sit down and discuss some do’s and dont’s. This is a common practice everywhere in the world and although it may be somewhat elementary or ‘trivial’ it is very important that it be down on paper and be used as a reference. This is not just a theoretical exercise but we are using this day in and day out at Times of India, Bombay.

Image quality improvement

PRANAV PARIKH: WE DEFINED THE GOALS AS fidelity, consistency and predictability. The single most important problem for the printer at that time was to match customer supplied proofs. The problem in 1994 is still matching customer supplied proofs. Where do we look for solutions? Equipment, materials, systems or communication? Clearly we need to communicate the limitations of the process. We need to communicate the pro- cess parameters and specifications for inputs and materials. That is the need today as it was in 1989.

“We need to understand the limitations of vision in terms of what the human eye can perceive and what we can consistently reproduce by using ink on paper.

“The real devil is dot gain. Dots determine tonal re- production which is the most important thing in matching colour proofs. The tonal reproduction provides the depth in an image; it provides the colour palette. Two dimensions only provide the resolution and detail, the third dimension gives you the depth and it is here that dot gain does the most harm. Total dot gain is the in- crease in tonal density of a mid tone dot from film to final print. Its made up of mechanical do gain and opti- cal dot gain.

“Mechanical dot gain is due to the increase in the physical size of the dot because of all the pressures that we are using and the squash effect. All impact printing processes have this kind of dot gain. Optical dot gain is the apparent increase, an optical illusion, due to the varying qualities of paper. Let’s assume that on the positive film the dot is 40%. On the plate it may be 35%. It shrinks because the dot itself has a fringe and is not of uniform density. This is known as dot sharpening in the making of positive plates. On the machine, the squash is generally around 10% which means that your original 40% dot has now become 45%. Then let us add an approxi- mate optical gain of 13% for a total of 58% which repre- sents a net dot gain of 18%.

“In negative plates the dot grows because the exposed areas become insoluble and there is undercutting and refraction of the plate exposing lamp. The 40% dot on film would become 43% on the plate and then you add on the 10% mechanical gain and the 13% optical gain for a net gain of 26%.

“In America 70% of printing is done from negatives. In Europe it’s the other way around. They started using negatives because of an early shift to wipe-on plates. With negatives considerable time is saved because the deletion of film edges and tape marks is not required. “Now with full digital pages where there is no strip-ping or deletion required there is a rapid shift to positive

for quality reasons. Europe and Japan are also on positive. “Circumferential and lateral slurring and ghost dots also add to the dot gain. Optical dot gain depends largely on the smoothness and efficient reflectance of the paper.

“If you have a good imagesetter, good film, good chemistry, a well controlled situation you can eliminate one area of dot gain.

“The SWOP standard is a typical dot gain curve which is acceptable in America. Wherever there is midtone in all three colours the dot gain can be expected to do the maximum damage. Influences on dot gain on the press. “Ink has the maxi- mum effect, temperature, the thinners that one adds to ink, type of blanket, pressure setting, damping solution, damping system, machine type, and the type of paper. Contrary to common belief the type paper has relatively less impact than the other elements on dot gain. The other factors can be controlled by the printer, and normally the type of paper cannot be controlled by the printer but it has less impact or effect than all the other factors put together. The type of plate and standardized plate- making process are important. The dot gain on an anodized wipe-on negative plate will be less than a presensitized negative plate.

“What’s the solution? The solution is to provide proofs which can actually be reproduced on the press. To do this of course requires proper communication between print buyers, photographers, designers, processors, plate makers and printers which can only be done if they speak a common language. Specifications are the language of print communication.

“Why do we need a standard? Let it be a low standard but let it be consistent. Let it specify a quantifiable level of achievement in each of the processes: separation, proofing, platemaking and printing. Often these happen in separate departments or separate companies. If they are working to different specifications there are bound to be difficulties. Separations from different repro houses come together on the same plate and on the same machine. And each machine has a unique fingerprint which keeps changing from day to day.

“Instead of muscle power we need to go to measure- ment, to quantification, even to settle quality disputes, And one could meet various requirements as long as specifications are followed. The American Association of Ad agencies, Business Press, GATF, IFRA, PIRA, FOGRA, FIP, International Association of Periodical Press, IPA, and national associations and bodies in Germany, Canada, Australia, South Africa all subscribe to this style of work- ing. They cannot reject a job that falls within specifications as a matter of course because these standards be- come contractual or legally binding.

“The necessary tools include a control strip: Fogra, Gretag, UGRA, etc. and a densitometer, a viewer. For viewing the colour temperature has to be 5000 K. In the course of getting support of allied industries for these specifications, the president of the paper mills associa- tion in India was quite surprised that printers would buy high technology machines at all. His standpoint seemed to be that the paper manufacturers should have been consulted and they would have advised the printers not to buy these machines if they required paper of these specifications to run on them. Although the ink manufacturers have been very forthcoming and very cooperative, ink manufacturers still give in to what process houses want and supply specially saturated inks for proofing. In fact they should be using special inks for proofing which emulate the dot gain on production machines rather than produce the sharpened effect that is achieved on flatbed proof presses. Thus what is needed is total understand- ing on all these issues. Remember, if you cannot mea- sure it you cannot manage it. Don’t go by visual judge- ment, you have to put everything down in a form that you can measure.” 

The practical experience of SSOP

PURNENDU SEN IN RELATING THE EXPERIENCES of his organisation in applying the SSOP standards, said, “I want to share with you my experience in imple- menting SSOP for over the last 5 years. Our objective results are that before we introduced SSOP our rejection or make good of colour ads was 25%. This includes dis- counts, make goods, disputes etc. This has come down to 1% and considering our colour ad revenue in Bombay is something like Rs 15 crores this is a significant recurring benefit and this has been achieved at an incremental pace.

“Secondly, we are investing heavily in expensive pre- press and press and post press equipment but we some- times we use very cheap materials. We little realise that if we have spent Rs15 crores on a heatset machine what is the harm in using the best ink. The cost performance of the best inks is really comparable if not cheaper. Thus, the fear of using inputs which seem more costly needs to be looked into.

“A few things we do everyday. The standards are given in the SSOP document. We blindly follow the standards given in the SSOP. We have imagesetters and typesetters cach with their own electronic test scale and on-line pro- cessors. Every morning we use the pre-exposed step wedge and we plot and check the end densities against the previous days’ or our standard. This establishes the chemistry and replenishment and temperature. Then we expose the electronically self-generated step wedge of the image- setter to establish the laser or exposing values are cor- rect. We carry out similar exercises for the camera. Our Chromalin proofing is similarly checked using a Gretag step wedge. We have a standard test form for our fac simile which we have pasted on a bromide page and we transmit it and we check it once in a week or once every two weeks. Then in the platemaking stage, we expose the Howson or Fogra scale. On all the plate exposing units and processors there are two charts. One shows the chemistry history, the temperature and proportion when it is changed etc. The other chart shows the step wedge expo- sure results in graph form.

“A test form is printed on each and every machine at least once in every three months. We read and try to match the values with the SSOP. If there is any deviation, we sit down with the ink maker and look at the other things such as blankets, fountain solutions, and plates. And then we come back to our scanning station to check for dot gain, grey balance, the transparency of the inks and then we refit these values into our system. It is as simple as that and all it takes is a bit of commitment. This is essential. One repro house in Bombay follows SSOP and we have never had a dispute or rejection on any advertisement processed by them and printed by us.

“On our Goss metroliner double-width press which runs at 60,000 copies per hour on standard newsprint with colour we were getting blurred dots and a ghost around the serifs of the text. We went into it, checked the fountain solution, impression system, roller setting, plates, changed the ink but all without results. We work in close collaboration with the blanket manufacturer. I got a list of blanket import batches from our commercial section to find out from when our problems began and I faxed these to our blanket manufacturer. I asked for the details and then I asked for rolling characteristics of the blankets.

“Every batch of blankets is measured for rolling characteristics by mounting the blanket on one cylinder in contact with another cylinder which is bare. This creates halation or doubling if the result is more than zero or our minimum acceptable limit as shown on a graph. By using blankets with acceptable rolling characteristics the problem was reduced from 100 to 10%.

“We have done similar exercises on fountain solutions and on hickies. These are just examples to show that when you get deeply into a problem and you have the will to solve it systematically then it can be solved.”

Queried about the quality difference between the group publications, Purnendu replied that he had been disturbed when many people said that only small owner-managed presses could deliver quality. And although his team strives to produce quality at high volumes it is difficult to deny that in low volumes the attention of the best man is there and slower speeds are also possible. “Nevertheless, we plan to produce the highest quality at 50,000 impressions now. per hour on a heatset machine within a year from

“We used to meet once in a month with the sales de- partment and the advertising department. In answer to the criticisms, we first streamlined our prepress. We brought in full page makeup. Then we went in for offset and heater. And then we went in for litho gravure, conver- sion gravure where we could accept positives. We react with a wogance to the advertising industry criticism feel Heat the small newspaper and regional papers need to treden themselves toward the importance of printing The owners need to consult their print man as much as their accounts, marketing, and editorial people and only sex down some guidelines in terms of efficiency and productivity. The troubles of the small newspaper all happen for the classical reason that the printing tech- nologist is not treated like a manager.”

Panel discussion on magazines, used equipment, and training

THE LAST SESSION OF THE CONFERENCE, IT WAS A suggested by the audience that the panel discussion dwell a bit more on magazines and magazine production.

George Jacob of Malayala Manorama, began, “We pro- duce a magazine called The Week which is done on an editorial system. Pictures are scanned in on a conventional drum scanner and stripped in manually. Deadlines were reduced drastically when we switched over to an editorial based system from a production based system. We have four vernacular magazines. We have been using standard software like PageMaker on standard hardware like Macintosh’s. We experience a lack of training for graphics artists or info-graphics and are forced to figure it out from manuals.”

Naresh Nath of Delhi Press talked about his organization’s experience, “We are producing magazines for the age groups 4 to 60 in seven languages for both children and adults. Our experience is that you have to know the language to really sell a magazine and this is the key to our success.

“Last year we launched the Gujarati edition of a lead- ing Hindi magazine Greh Shobha. The Hindi circulation was 350,000, and the Gujarati circulation is already 85,000. We naturally believe that there is a great future for vernacular publications.

“Apart from that we have a new magazine that we started last year, Saras Salil, which is meant for those with a monthly income below Rs 1000 per month. For those who cannot afford a daily newspaper. We have priced this 32 page magazine with 16 pages in colour at Rs 2 and we print it entirely on heatset web. It started with 80,000 and it has crossed a circulation of 700,000 per fortnight. In English the circulations have stabilized or are increasing slowly compared to the language publications However the pro- duction values are becoming very critical, the advent of colour television advertising has led to the linking of co- lour ads in magazines to the television campaigns. We find that this kind of colour quality is only achievable by the heatset process. The other bottleneck when circulations are rising is binding.”

“While electronic media seems to be competing with the high circulation English papers, it seems to be helping the language papers with colour advertising. Earlier, the vernacular papers only seemed to attract advertising for down market products or necessities.

Reiner Ebenhoch added, “The magic words are: cor- porate image. McDonalds or Coca Cola would never advertise in black and white. If you are able to offer colour you are offering a much bigger market to your advertisers.”

Arun Shankar of the Dataquest group, which produces four magazines, asked, “How would a pagination system work for magazines? Magazines have a greater number of pages, 160 or 200. How would the system display your production decision system? Another difference might be that several magazines with separate editorial systems share common production and business systems. How would one pagination system handle this kind of problem?

Reiner’s answer was that, “Totally different functionality is required for newspapers and magazines. In a newspaper you have many stories on one page and in a magazine you may have several pages for one story. P.Ink has a market base of 60 % newspapers and 40% magazines, including Focus in Germany and People and Fortune of the Time Warner group. We make very consistent use of the SQL database. This modular design allows all departments of any production step or process in a magazine or newspaper to communicate with each other.

“We believe the key issue is the division of labour to divide and distribute the workload. All the elements can be tracked by everyone who is connected to the data- base. We can display 128 pages on a screen but they would be too small. You could display 16 or 32 pages and scroll through the pages, the physical limitation of the screen doesn’t allow more than 32 pages to be displayed sensi- bly.”

George Jacob added that, “One section of a magazine on the screen should be enough. Four different editorial systems can be linked to the same database. A newspaper works in real time every day. A magazine has a longer cycle. The main thing that a database does easily is to avoid duplication of stories.”

Arun Shankar, still unsatisfied, pointed out that in a newspaper system at two at night you can actually see the page but in a magazine the delays are even more than that.

Purnendu Sen advocated a system study. “Is it the edi- tor or is one individual looking after a certain number pages or section or subject? A tracking system has to be developed on the basis of editors or groups or sections of pages or subjects.”

Patrick Venn of ATEX, commented, “With a magazine some of the pages would be locally paginated. With a magazine of something like 160 pages a production tracking system is essential.” Reiner Ebenhoch, reiterated that “Only with pagina- tion systems can you have tracking and imposition. You can track your pages according to your signatures.”

Pranav Parikh said that, “In magazines the pagination systems are most cost effective in India. This is where the maximum savings are and where they could enter into the industry in a big way.”

On the issue of in-house colour for magazines, Pranav Parikh said that “With digital prepress the savings directly accrue to the publisher, especially if they have their own printing facility. If your volumes are lower and your quality requirements are extremely high then it may be easier to continue to go to a repro house.” Reiner Ebenhoch added that “It was true even five years ago that it was easier to find a man to fly a jumbo jet than to find a scanner operator. You need to have the people who un- derstand colour. It still needs people who understand the context of colour in its total sense. If you bring it inside you must have the people.” The moderator, Viren Chhabra asked: “Do you think that the suppliers of high technology have an obligation to help us to train people in the new technology.”

Pranav Parikh replied, “Like all other issues this will also be settled by competition. If vendors want a higher market share they will offer value added services. Since all hardware and software will be similar the only way to compete will be on the basis of intangibles such as train- ing. Heidelberg’s success is linked to its school. I am sure that ATEX and Scitex are all thinking on these lines. As a vendor we have made a commitment to set up a training establishment for which the industry has made the initiative. However, I don’t think the owners or the users can disown this responsibility. Loyalties come when people learn.”

Kek Hwa Choon added, “Since last year our practical experience is that in many cases the ability to use the equipment is very low. The basics are important although it may at times seems repetitive. We look at training as very important. And also the training in workflow. We do it for ourselves. I think there is certain equipment such as the flatbed scanner where we will be running courses so people who may not even have bought the equipment can have a go at it.”

Viren Chhabra said that, “Many of us invest in second hand equipment. How do your ensure the availability of spare parts? Often a small circular comes and says that spares will be discontinued on a particular date. What do we do for maintenance?”

Naresh Nath of Delhi Press clarified that his organisation never buys secondhand equipment and George Jacob also suggested that second hand electronics are not ad- visable.

Kek Hwa Choon speaking on this issue said that “Be- cause of the newer flatbeds, drum scanner prices have come down. Even relatively modern used drum scanners are being imported into India. Even the spares are avail- able but the real issue is that the running cost is very high. The duty is very high on spare parts.”

As the conference wound down to its end, Viren Chhabra thanked the presenters and reminded the participants that one of the key benefits of these kinds of functions is the opportunity to meet other users. “Although we have come to the end of our conference, at the end of the day it is our own network that counts,” he said..

Naresh Khanna, on behalf of the organisers thanked the participants and said, “We hope that this can be an annual event. That we get a positive response from the participants. That the participants from abroad think it is a worthwhile activity. I think we can do it again next year. The strategy is to make it an annual conference, that is, always after IFRA, after Diwali and before Christmas. So we would like to develop it as an Indian event, a South Asian event. There are many decisions to be made such as whether it should be a two day event or a three day event. Some people have said that we should not do it every year.

“It is up to the participants and to the industry as a whole whether it is worth building this up as a compact self moving activity with a very cost effective management and not a very elaborate management. We have not asked in the questionnaire what you think the conference should be about since we really see it as our full time job to get feedback and to motivate people and to improve all the inputs and facilities.

“Obviously this year there were many constraints. It was an almost foolhardy attempt and although the participants seem very pleased, we were very fortunate to get, in a short period of time, very high quality inputs. We really think this is a great forum for the people who have been doing things in this industry and we’ve been lucky to get some of the hot shots from all over the country. Of course Tapash has not come and GS Mani could not make it at the last minute. Panchanatham has recently had surgery and was not well enough to travel. We see this as a forum for people in the industry. They have to learn to prepare the material. They have to learn to share. We must create a platform for them to share and they have to learn to be as articulate as Purnendu and Pranay and they have to scientifically present their conclusions. This is our idea and although we’re a small organisation we can make it work. This is an annual event and we’re ready for it. Thanks to all our friends and to all of you.”

Prepress Technology for Magazines and Newspapers

A two day conference at Hotel Holiday Inn, New Delhi ORGANISED BY INDIAN PRINTER & PUBLISHER standards for the eventual digital transmission of colour advertise-

A panel of international and local industry professionals will take up for discussion, editoments. rial front end systems, high end colour for magazines and newspa- pers, output devices such as communications for complete pages including halftone colour separations

The tentative programme of the two day event includes presentations on industrial strength front PostScript imagesetters and tele-end systems with special attention to full pagination, colour and Indian languages.

This is the first of what we hope will be an annual event and it is meant for senior technical person- nel in newspapers and magazines to share their experiences and to positively interact with leading technology vendors presenting the state of the art.

Thus far, international industry experts who have confirmed participation include Bill Solimeno, Industry Consultant from the United States; Patrick J Venn, Atex Publishing Systems; Dennis Doolittle and George Meier of Autologic Ashish Chowdhury of Hughes Escorts Telecommunications Systems, and Bernhard Marbach of Scitex/PInk Senior representatives of the Telecommunications Ministry, Government of India will be invited We also hope to sensitise advertising and media and production participants to the newspaper and magazine industry’s concern for page.

Communication systems based on VSAT technologies will be dis- cussed with reference to the trans- mission of full PostScript pages. There will be extensive interaction among participants and panel discussions of open system, stan- dards, as well full page image-set- ting with PostScript colour.

We hope to have the stars of the Indian publishing industry, both the ones who have made us proud over the years and those who will have to sort out the technology issues in the competitive future.

This is your chance to leam, to ask questions and to share your experiences of the turbulent technology that is daily transform- ing our industry and giving the edge to those who can figure it out and make it work before others Find out. Get organized. Participate. Call us for the detailed programme brochure. Or fill out the registration form on the facing page.

 

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