B2 printers who opt for ctp face a further decision. Should they choose a thermal or a visible light solution? By Marion Wilson.

B2 printers following B1 companies down the ctp track are confronting a dilemma. When it comes to plates and platesetters should they opt for a thermal or a visible light solution?

The protagonists for each technology put forward a very persuasive case so extracting the facts from the hype is far from easy for newcomers to the ctp scene. A growing number of suppliers including Heidelberg, Agfa and Fujifilm Graphic Systems are backing both horses by offering the two systems.

Informed decision

Fuji's group product manager Steve Cookman says: "We believe in offering unbiased advice and allowing customers to make an informed decision. Luxel Vx-6000 CTP (violet) can be a very attractive proposition for many commercial printers as can the Luxel T-6000 CTP (thermal) with Fuji's Brillia LH-PIE thermal plate."

However, the relatively new technology of violet ctp is rapidly gaining ground, especially where cost is an influential factor. "The Vx-6000 uses a 30mW low cost, long life violet laser diode that with internal drum imaging leads to a very low cost of ownership," says Mr Cookman who claims that the latest version of Fuji's photopolymer plate (Brillia LP-NV) can match the print quality of thermal systems for 175/200lpi commercial print. "Under the microscope thermal dots might look sharper," he says, "but if you could have a system that consistently met your clients' requirements, produced twice as many plates per hour and cost less to run then you'd have to think seriously ­ it's about making an informed choice."

Fuji's thermal and visible light solutions can be driven by either Celebrant (built around the Adobe Rip) or Valiano Rampage (built around the Harlequin Rip) both of which offer Rip Once Output Many (Room) capability for complete data integrity. Rampage can also directly drive many different output devices where the new system has to work with existing equipment. The Vx-6000 semi-automatic platesetter with Celebrant Rip and processor lists for around ?00,000. An entry level T-6000E configuration with Rip and processor is ?0,000. Both include installation, training and 12 months warranty.

Jim Todd, sales director of Heidelberg UK, says: "Most B1 printers now have ctp and since its introduction we have seen thermal technology take hold in the larger, high volume print houses. The B2 and B3 markets are following on. Any company that is still using an imagesetter, film and plates must be struggling to remain competitive." Heidelberg has made improvements to both its thermal and visible light platesetters. Its Prosetter violet systems are now equipped with a new laser head that can be switched from 5mW for silver halide plates to 30mW for use with photopolymer plates that are better suited to longer run work or UV ink applications. The Topsetter has been enhanced to cater for a wider range of plate formats from GTO to B1+ at a faster rate of 20 B1 plates an hour at 2400 dpi.

Agfa launched its thermal Xcalibur 45 platesetter with external drum imaging at Ipex 2002 but systems product manager Colin McMichael believes that violet diode's inherently lower running costs make it the better choice for B2 printers. For these customers Agfa offers a package comprising a Palladio B2 platesetter with an Apogee Rip and Print Drive and auto-loading plate manager for around ?0,000. Mr McMichael comments: "Most customers in the B2 market are commercial printers with runs below 350,000 so speed and the ability to produce 20 plates an hour are important considerations ."

Tight margins

Derek Sizer, managing director of ECRM, agrees that visible light is the best option for the B2 and B4 markets where margins are tight and more plates are needed for short run work. He argues that although there is currently a bigger choice of thermal plates from different manufacturers this is set to change and predicts that by the end of this year a number of new companies, including Lastra, will be selling violet plates.

When it comes to cost, not every printer moving into ctp wishes to invest in a whole package including workflow. Many are looking for a platesetting system that will fit in to their existing workflow and there are a number of suppliers who can meet this requirement. ECRM, for instance, has just launched the Mako 4, described by Mr Sizer as "a very simple hand-fed machine aimed at the four-up market".

Priced at ?0,000 it comes with three pin bars for different press configurations and an online transport system that can go straight to a processor. Whether it is online or offline, the Mako is designed to slot into the user's existing workflow. "You could virtually unplug your imagesetter and put this in its place because Mako works with any Rip that produces a one-bit Tiff. It comes in two versions: either 30mW for use with Fuji's photopolymer plate or a 3mW for use with silver plates from Agfa and Mitsubishi," says Mr Sizer.

In the same price bracket, HighWater's Platinum flatbed platesetters use violet lasers for working in yellow, near daylight conditions and come in two versions. The 2218 (maximum plate size 525x459mm) ­ priced at ?8,000 ­ is for two-up B2 while the 2230 (maximum plate size 745x605mm) ­ priced at ?5,000 ­ is for four-up B2. Both use Mitsubishi SDP or Agfa's Lithostar LAP-V metal plates.

Sales and marketing manager Sue Wood says: "The Platinum is simple to operate because it is so similar to a traditional printdown frame that a printer can be producing press-ready plates on the day of installation." Manual loading and unloading also makes for ease of use and HighWater claims it takes only three minutes to load, expose and unload a plate at 2540dpi. The average output from the two machines is said to be around 750 plates a month on the 2218 and 2,500 on the 2230.

Two other manufacturers that have introduced platesetters aimed at the B2 sector are L黶cher and Krause. The latter's LS70 is a violet or green visible light device incorporating the internal drum technology Krause uses in its B1 models. Trevor Darlington, director of UK supplier Krause DtP, describes the LS70 (priced at around ?0,000) as a "plug and go" machine that connects with existing workflows. L黶cher's Xpose 75 4-up platesetter is a thermal platesetter that also features an internal drum design but one in which the laser diodes, rather than the plates, spin round. The Swiss manufacturer claims this gives greater accuracy by eliminating loading, vibration and balancing problems. Distributed in the UK by Turning Point Technologies, the Xpose 75 costs ?5,000.

Twice the productivity

For printers with more money at their disposal, thermal becomes a feasible option. Screen UK has two thermal devices; the entry level PlateRite 4100 at ?1,850 and the PlateRite 4300 which costs ?0,600 and gives twice the productivity at 20 plates an hour.

Then there is a choice to be made between manual, semi-automatic and multi-automatic loading. Managing director Brian Filler says: "A B2 printer with only one press needing 300 to 400 plates a month would be advised to go for one of the first two options but a company with two or three presses and a plate requirement of around a thousand a month should look at multi-automatic." Not surprisingly, Mr Filler subscribes to the thermal school of thought. He reasons: "Thermal is completely daylight operational which, unlike any of the visible light alternatives, gives a printer the option of imaging processless plates in the near future. Another benefit for a printer who opts for thermal at this point in time is that he has the choice of as many as eight different suppliers instead of being tied in to one or maybe two plate manufacturers."

KPG is well known as a supplier of thermal plates and its website (www.kpgraphics.com) gives a comprehensive list of the advantages to be gained from thermal technology. These include long runs without post-baking, no need for silver recovery and the ability to carry out stochastic printing.

The Big Daddy of thermal ctp is Creo. Co-founder of the company, Dan Gelbart, states: "Thermal imaging technology delivers better imaging fidelity than violet light systems because of the binary nature of the thermal media ­ it is either exposed or it is not."

Range of options

Creo's Lotem 400 devices for the B2 printer come with a range of options from semi-automatic through to fully robotised giving an output of up to 35 plates an hour. An entry level package comprising a Lotem 400 bundled with a PS/M software Rip for ?7,639.

It is now eight or nine years since Purup introduced its first B1 platesetter and in that time its products have gained a reputation for superb build quality and accuracy. Purup has moved on through various amalgamations and now has worldwide ambitions as Esko-Graphics. The attention to detail and build quality that made the Magnum so recognisably a premium product is now personified in the PlateDriver. But there is a versatility and functionality designed into the PlateDriver that gives Esko-Graphics a tool that allows it to challenge the market on many fronts.

Possibly its best design feature is that the imaging source is remote from the mirror carriage resulting in the potential for a much more extended life. As well as being able to field upgrade the imaging light source, the PlateDriver can also be changed from B2 to B1 in the field. BasysPrint, is a very different animal from most ctp systems for it uses a standard uv light source to expose conventional plates. It does this using an electronic grid system to switch the light source and resolution is interpolated to give the effect of 2,400 dpi. As a system it has been around for many years, but its take up in the UK has been very modest.

 

[时间：2003-06-05  作者：Bisenet  来源：Bisenet]