Re: Scanner Training Advice (was: UCR vs GCR...or Neither - RAW CMYK?)


Martin Orpen <orpy@...>
 

on 9/10/01 1:39 pm, samarsh@... at samarsh@... wrote:

4. Black and white prints. Take one of these along as a test of
the
scanner's light source.
Are you referring to native scanner RGB grey balance?
Sorry, I didn't make myself very clear on this point.

The light source on the flatbeds is extremely critical when it comes to the
apparent sharpness of the images. IMO the first Scitex and Scanview flatbeds
produced horrible, oversharpened images. The results from photographic
prints were pretty much unusable unless the USM was turned off!

The smallest specs of dust or surface imperfections were magnified, so your
high quality fibre print ended up looking a real mess.

Scanview have since modified the light source to make it less focused and
more diffuse -- this cured the problem.


Each time you check a new area of the image, its a new 'max
detail' scan. This can take about 30 seconds just to evaluate the
USM.
This is similar to our scanner -- we get a general preview that is fairly
mediocre -- but can choose to scan a portion at final resolution before
committing the whole image.

Unfortunately you just have to keep a bunch of settings in your mind --
ColorQuartet allows adjustment of strength, noise, light contours, dark
contours and contour thresholds. With power comes the responsibility to
RTFM!

There is a weird table called 'LUT.id' which I cant find any
mention of - but I presume it is something to do with calibration.
Lut is a look-up-table which is probably used to display your image on
screen, or convert native Lab data to RGB.


There are also 'device link profiles' which are a proprietary
combination of tables/profiles/scanner settings which are
presaved into a 'profile'.

This does not seem to be a true ICC profile - but a proprietary
one.
Proprietory always bothers me -- which is why we don't buy much Scitex kit.

--
Martin
Idea Digital Imaging Ltd - the "image" specialists
http://www.idea-digital.com

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