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| Payback of color register control |
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Overlooking these factors, the color-register awareness has grown drastically last years and this development looks a little bit similar like the development in heatset magazine-printing. When in the eighties the number of new presses at higher speed increased significantly, the printing-contracts with magazine publishers became tougher and tougher due to a necessary cost-cuts in economy of printing. Since then, heatset printers continuously try to wrench every penny out of their presses' start-up and running efficiency. It's a well known fact that the heatset-segment is characterised for it's very tough competition, which is the leading factor to judge press-automation auxiliaries like color- and cut-off register as absolutely normal. However, newspaper printing feels competition differently, due to ownership structures. The newspaper publisher is much more keen on minute-deadline matching compared to a magazine publisher. That was a major reason to handle quality differently in the past. But as soon as advertising figures go down, the interest in quality goes up and additionally the need for efficiency improvement as well. Q.I. Press Controls has to deals with these tendencies and did a good job by preparing themselves in giving the market improved information about the added value of their Intelligent Register System color- and cut-off register system, when it comes to decision-making discussions with newspaper managers concerning pressroom efficiency. "Since commercial coldset will tackle the lower heatset market and newspapers comes under advertising budget-pressure, the theme of automatic color- and cut-off register gains increasing attention from print-management. Obviously, presses become too expensive per hour to allow any loss of effective hours and/or material" says Menno Jansen. During a discussion we compare total press-investments with the investment for an automatic Intelligent Register System color- and cut-off register system. It's just e few percents of the press-investment to put on the press for a return within a very short period of time. QIPC knows that specifically because a number of customers decided in favour of an Intelligent Register System-system for color- and cut-off register after a period of printing without any automatic registercontrol. So affectivity of waste-reduction could be counted. A British customer counted a payback period of eight months and gains now a minimal annual saving of 180.000.- Euro on paperwaste, apart from savings in effective presstime. Intelligent Register System Colour Register System; the three legs Intelligent Register System stands for 'Intelligent Register System and it's intelligence basically improves the intelligence of the press and in particularly the operation-effectiveness of pressroom operators. How? Like most color register-systems Intelligent Register System comprises three major components: processor, register-mark detector and register-marks itself. In particular the Intelligent Register System distinguishes itself from other systems on detector and register-marks in particular. Processor and software are dedicated and hardly visible on most presses, because on new presses these components are integrated in the press drive-system and commanded through the same keyboard and touch-screen. The registermarks are completely different from the well known solutions. Due to application of a fast operating CCD-camera the small register-marks act like a picture. Other systems apply line-scanners which detects begin and end of key-element and the processor counts the distance between the marks. Comparison between actual- and setting-value will conclude in a correction-signal or not. The Intelligent Register System' registermarks is that small (0,04 mm2) so the human eye can hardly detect the element. In newsprint normally the set of registermarks need a white space of 5x5mm in which eight tiny targets (two for each CMYK color or more in case of spotcolour + CMYK-printing). Thanks to CTFilm or CTPlate it's not too difficult to get these tiny targets on printing plates. Due to invisibility by the human eye, the Intelligent Register System registermarks can be positioned somewhere in the editorial page. So there is no conflict or difficulty to copy plate-edges, because the registermarks aren't necessary to be positioned in the spine, where other clearly visible elements have to be positioned in most cases. The eight tiny target-elements have a theoretical ideal and interrelated position within the square 5mm white space. Exposed in one go with the fullcolour images on films or plates, these will print in perfect register as soon as the targets have their ideal interrelated position during print. Obviously one has to realise that just one registermark is required on the plate-cylinder. Cylinders will be wrapped with single page plates or panorama plates and one should consider the most optimal position in approximately the centre of width to compensate for fan-out. Like printing without a color-register system will be served also by a very precise and accurate maintenance of the plate-register on the plate-cylinders, this is an absolute condition to make a color-register system fruitful. So, a very precise maintenance of plate-register from copy-department till register-pins on plate-cylinders has to be guaranteed. One of the presently available punch- and plate-benders, equipped with CCD register-crossmark recognition will do a good job to fulfil that condition. Register-detection is the job for the high-resolution fast operating Intelligent Register System CCD-camera, driven by well proven software for a very fast picture-analysis. The picture of the multicolour target-matrix, found by the camera after press start-up, will be analysed one time per press-revolutions. The difference between theoretically ideal interrelated position and real interrelated position of the targets is calculated very rapidly and converted to steering-signals for adjustment of the plate-cylinders by the drive motors. The advantage of this camera-type is that a printed web should not specifically run over a roller in order to create a fixed measuring point. As long as running paperweb stays within a free web flutter of plus and minus 7mm the Intelligent Register System-camera can run properly. Recto and verso side of the color-printed web should be measured as soon as possible after leaving the printing tower. The closer to the printing tower, the better the conditions are for a very fast reaction time of the Intelligent Register System-software on servo drive-motors. Although fan-out is a subject that can behave differently depending on printing principles, printers operating with an Intelligent Register System color-register can rely on the fact that the register gets automatically in theoretical ideal position within the shortest period of time. That position will be based upon center-to-center related position between the different color cylinders. On condition that a certain pre-allocation (based upon standard fan-out behaviour) has already been incorporated into the printing plates, the press operator just needs to inspect the still resting deviations from an ideal color-register on the web-edges. As said before, any color register-system has to rely on a perfectly maintained register of all printing plates united on one plate cylinder, from copy-department through the plate-bender till on press. So does the Intelligent Register System-system. Profit of the system To achieve a stable printing process as soon as possible after press start-up, the setting speed will be chosen as close as possible to the limit of the running speed. But in practice, when acting without color register-systems, operators set the press start-up speed on a level that gives them sufficient time for folding/cut-off control and adjustment, color-register and color-balance. With this procedure one tries to avoid too many waste-copies. Later speed-increases need additional adjustments on the mentioned elements. But a quick printing-balance incorporates the achievement of quick quality-balance and will be facilitated by a very rapid optimisation of all mentioned factors like speed and register during press start-up. The full automatic Intelligent Register System-system has already proven many times that it is built for that facilitating task and will take over the printer's job of getting a copy and inspecting through the copy what adjustments he has to make. Intelligent Register System does that thousand times faster, which will save tuning-time of the press and reduction of waste copies. This specific saving performance during start-up of newspaper presses is not just valid for four-high presses, which is the common idea. Neither a four-high nor a satellite press will print in register from it's first revolutions on. Neither it will be so after a plate-change nor with a restart-up after a web-break. Only a lesser or wider variation might be applicable depending on press-configuration, but will depend on paper-quality, status of the blankets and printing surface as well. Although a fullcolour printed page may look quite heavy, an individual color can have just small ink-occupation and ask for more dampening than the black. This will happen color-after-color till the black is printed, which will affect on paper-fibre swelling. Combined with printing tension one may assume that satellite printing adds the dampening and stretches the web just by 50% during recto-printing and the other 50% during verso-printing, whilst four-high printing adds 100% in one go by printing blanket-to-blanket. This principle-difference means that satellite-printing might be in a more favourable condition and create less color-register by fan-out, but even the fewer swelling will have some register influence. Depending on quality-demand in advertising (e.g. by multicolour small diapositive texts) adjustments will be necessary. Next to that the physical circumstances of the press plus the mechanics of the printing process make that after start-ups and re-starts an acceptable fullcolour register won't be there without any interference. Not just on four-high presses the operators have to interfere but also on satellite newspaper presses. Cut in start-up waste and improved running-up conditions will be the leading factors for pay-back for satellite-presses as well like proven on a number press-concepts during the five years Q.I. Press Controls is operating now with an installed base of controlling the color-register position of 751 plate-cylinders on webpresses. Experiences in the past and parallel printing industries have shown that automatic color- and cut-off register-system have reduced crew as well. The average experience is heatset weboffset means that -apart from reelstand- and pressdelivery-operators the printing crew could be reduced by one-third. Anyhow, newspaper pressrooms could start to analyse their potential savings in terms of material, time and crew. |