Digital BW, The Print

Hi Bill,

Nice to see someone is trying real images.

You mention using both 8 bit and 16 bit files -- are they the same basic
data?  I.e. was all the image creation done in 16 bit and then just
at the end convert one copy to 8 bit in Photoshop?
Printing both of these with the same driver and same settings ought 
to tell you if the 16 bit version makes any visible difference.

Roy

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, BKPhoto@a... wrote:
> 
> In a message dated 1/14/05 10:28:11 AM, tyler@t... writes:
> 
> 
> > Long ago, testing with a different RIP, I did see a difference,
> > sometimes. Since the RIP I use accepts hi bit in, I'll just stick with
> > it to make sure I'm getting the best possible for now.
> > It's working, and at some point it's more satisfying to make prints
> > than tests.
> > 
> 
> Guys-
> 
> I've been following this thread and would like to mention something that 
> dovetails with Tyler's comments.
> 
> Recently I've been testing a number of RIPs (ColorBurst, ImagePrint, Bowhause 
> and Lyson's Daylight Darkroom based on Bowhaus, and QRT) on a 7600 and 4000, 
> both with UC inks. My initial interest was to compare the supplied profiles. 
> The idea was to establish a baseline: what kind of print do these applications 
> produce out of the box (I've built custom profiles for the ColorBurst RIP, 
> using the i1 spectrophotometer and MonacoProof and compared those to the 
"canned" 
> profiles, as well).
> 
> I ran a series of test prints with a healthy 8-bit grayscale file, another 
> with a good 16-bit grayscale file. Both had 21-step tonal ramps attached, which 
> was very helpful.
> 
> As you might expect, each RIP produced distinctively different prints. They 
> all did a good job; each is an improvement over the OEM print driver. However, 
> I've noticed a difference in the 16-bit test prints made with IJP/OPM (made on 
> the 4000). It seems to do a better job with local contrast. Similar or very 
> close tonalities separate better, giving the print an improved sense of overall 
> sharpness and depth. It is definitely noticeable to the eye.
> 
> I have no idea if this is directly attributable to IJP/OPM's internal 16-bit 
> architecture, and I have no way to objectively test this, but it makes 
> intuitive sense to me. Better data in, better data out provided each link in the 
> imaging chain does it's job properly and is managed properly. There could be many 
> other factors, of course. It could be that the IJP/OPM's canned profile 
> happens to match-up well, with the printer, ink and paper combination I used. 
Maybe 
> the planets were in alignment. However, I'd also say that the IJP/OPM print is 
> at least as good as those made with my custom profile. Not bad, especially 
> considering the difference in cost and the time one has to invest in the 
> learning curve.
> 
> 
> 
> Bill Kennedy
> Associate Professor of Photocommunications
> St. Edward's University
> 512/448-8680
> 
> 
> [Non-text portions of this message have been removed]