Optimum output
The quality of output
available from digital printers has improved
enormously over recent years. Some photographers
find they actually prefer the print quality
produced by high end bureau machines. I see two
reasons for this: The ability to finely control
the colour output yourself and the wider choice
of paper bases available, compared to RC plastic
matt or plastic glossy.
When a computer is instructed to print a
document, graphic or photograph, the data has to
be converted into a digital language the printer
can understand. Cheaper Mac colour printers use
Apple's 'Quickdraw' - the same language that
describes how documents appear on the monitor.
This internal processing method has its
drawbacks, chiefly the incredible length of time
it can take to print out even a medium sized
colour picture, plus we're talking basic inkjet
machines here which are hardly capable of
delivering photographic quality. A better method
is to process all the information either via a
separate computer, or using the printer's
internal memory - a process known as Raster Image
Processing (RIP). For example you'll notice many
printers come supplied with Postscript (level 2
is best). This is the page description language
developed by Adobe. Once processing is completed
the document is ready to print in one smooth
operation. Printing speed is therefore dependent
on the type of print driver software the printer
uses and the amount of RAM memory installed in
the machine. Too little memory and either the
document will take ages to process or won't print
at all.
There are so many Postscript
printers to choose from in the under £10,000
desktop market - which one you should go for
depends on the type of colour work you do.
Inkjet, thermal wax or laser printers are useful
to graphic designers where the low cost of
consumables such as paper and toners is a major
consideration. For professional imaging purposes
though, the best solution is to buy an A4
dye-sublimation printer, prices of which vary
between £1,500 - £10,000. Dye-sublimation is an
RGB colour process in which a specially coated
receptor paper is overprinted with three
transparent colour dyes which diffuse into the
surface. Better machines such as the Kodak XLS
8600 (basic price £6,500) are capable of
delivering excellent near photographic quality,
glossy colour prints in under 75 seconds. Higher
specifaction models such as the XLS, allow more
control over the final print size with a full A4
imageable area. Dye-sub prints can't match the
archival permanence of a conventional colour
print and are known to be unstable. The print
dyes may react when they come in contact with
soft plastics such as transparent portfolio
sleeves or are heat sealed. Kodak have addressed
this problem by introducing a special
'Extra-Life' printer ribbon which will coat the
print surface with a transparent protective
layer.
I'll briefly
mention the Fargo Fotofun A5 dye-sub printer -
this little gem attracted a great deal of
attention at the recent Apple Expo and with a
price tag of £300, it's easy to see why. The
results I saw were quite reasonable and with the
A5 paper costing less than a sheet of polaroid,
this might make a useful intermediate proofing
device with several useful applications.
Many colour labs and bureaux also provide a
dye-sub printing service for both A4 & A3
formats, but there are also other types of print
output available which use hardware normally
beyond the budget of a small studio. First there
is the A4 Fujix Pictrography process which most
experts agree gives a true photographic finish.
Instead of three passes (as in the dye-sub
process), exposure is made with a thermal laser
diode once onto a silver halide donor paper,
followed by a thermal development transfer to the
receiving print, which Fuji claim has the
permanence of a conventional colour photograph.
Admirers of the New York based photographer
Raymond Meier, may be interested to know that he
supplies all his editorial clients such as
Harpers Bazaar with pictrographs as finished
artwork. Fuji have plans this year to release a
desktop machine which uses a similar process to
Pictrography, known as Thermal autochrome. Expect
the price to be around the £5,000 mark.
Digital
prints
For blow-up prints, poster
inkjet plotters are capable of printing up to A0
size. These outputs are suitable for all
commercial purposes. Inkjet technology has
improved to the point where very fine resolutions
of 300 dots per inch are now attainable. The inks
are more colourfast and can be guaranteed to last
longer than before. One of the latest and best
models is the Hewlett Packard 755CM Designjet.
For exhibition quality work you should consider
looking at fine art Iris prints. Richard Mathews
(AKA Harry) of Quicksilver in Covent Garden has
spent the last two years testing and refining the
process on various archival quality paper
surfaces. The results I saw showed Iris's
potential to capture delicate colour tones on
different types of fibre base. Iris proofing has
taken off in the states as a medium for
exhibiting and selling art photography - whether
manipulated or not. David Byrne's recent
exhibition at the Photographers' Gallery were all
Iris prints. You'll need a pop star's income if
you're thinking of having your own portfolio
reprinted because they can be very expensive (up
to £600 per print). Though prices start at £70
up to A3 on art paper and prints on normal stock
will cost about the same as an A3 dye-sub.
Colour laser copiers can be linked to a computer
via an image processor such as the Efi Fiery.
They are ideal for producing intermediate proofs
and short run printing. Metro for example offer a
composite card design service with colour laser
run ons from as little as £1.05 each. If you
supply your own layouts on disk to be printed
seek advice on preferred page layout
applications, file fomats and print resolution.
Depending on how you supply your work and the RIP
used by the bureau, image processing can take
anywhere between 5 minutes to half an hour for a
single A4 page and some bureaux charge their
computer time by the minute!
Having outlined the range of services available
from colour bureaux, which is the best removable
drive media to transport your digital files
there? Syquest EZ and Iomega ZIP drives are
highly rated for their reliability and because
they are cheap to buy. However, most bureaux
still only accept the Magneto Optical and older
Syquest formats. These drives are more expensive
to buy, though of course this may all change in
the future. It's just that with so many different
media formats about these days, itÕs worth
checking which ones your bureau uses.
Calibration
Calibration is important.
There will always be variations in colour output
between different printers and the only way to
guarantee consistent results is to run a test,
and then adjust your Gamma control monitor
settings by comparing the printed result with the
screen picture and saving these for future
reference. Metro Imaging and Joe's Basement will
supply their customers with a test transparency
and its original on a floppy disk to help you to
make a comparison. Colour laser copies direct
from disk always print a lot darker than you
might expect. Once the screen is calibrated you
can overcome this problem. Where a printer is
connected direct to your computer you can also
adjust the print transfer functions via the 'Page
set up menu' to achieve good colour and tonal
matching with the monitor.
In conclusion I would say that at the very
minimum you should buy the best desktop
dye-sublimation printer you can afford. If your
budget will stretch to £13,000+, you could
purchase the Pictrography 3000 or wait to see
what the new Fujix Thermal autochrome process
promises. If these are all beyond your means,
then stick to transfering your files to a good
bureau. I firmly believe that photographer will
always be best served by the processing houses
which provide bureau facilities such as Ceta,
Sky, Tapestry or the others I mentioned earlier.
These companies specialise in electronic imaging
for photography and will be far more sympathetic
to your needs. They've certainly been patient
enough to answer all my questions over the years.
Copyright - Martin Evening 1996
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