Digital BW, The Print

David Murphy wrote:
> So I'm new to this but am now at least knee deep in seeing what is 
> possible w/ modern inkjets for b&w.  At the moment I have an Epson R280 
> loaded with the 6 cartridge Eboni inkset from MIS.
> 
> I shoot two films, Ilford HP5 and Delta 3200 in both 35mm and 120mm. 
> I'm quite happy w/ my film and processing methods.  Scans look great. 
> Traditional wet prints look great.  Some of my new inkjet prints look 
> great, others look very bad.
> 
> As a generalization it seems like in some circumstances and with some 
> photos the printer is able to convincingly render the film grain and 
> it's gradations smoothly and in other cases it can not.
> 
> Where I notice this most is usually with people's hair or beards.  They 
> often appear very splotchy as if the printer is printing straight black 
> or white and doesn't understand that there should be a gray transition 
> in between.  These are mostly natural light candids on 35mm where grain 
> is fairly visible.  I like grain.
> 
> What confuses me somewhat is that if I take the identical file and print 
> it out with QTR in Black Only mode, QTR seems to handle these 
> transitions in tone much more smoothly and hair is rendered much more 
> convincingly as opposed to splotchy. I would just print with QTR but I 
> do not like the brown look and I greatly prefer the overall tonality of 
> the 6 cartridge setup.
> 
> So, if the above makes any sense, am I running into a limit of the 
> technology or am I doing something wrong?  Why is QTR rendering hair 
> much more convincingly using only one cartridge?  What should I be 
> experimenting with?


In your case it is more  likely the better tonal 
distribution through QTR than what is possible (or harder to 
achieve) with the normal driver. But it could as well be one 
of the issues below.

At some stages in the process aliasing can occur. At the 
scanning phase the actual grain can more or less accumulate 
to larger digital grain. Grain effect (and noise in digital 
images) can also increase when downsampling is done without 
proper anti-aliasing filters. If the software you print from 
leaves the downsampling to the printer driver and the last 
has inferior downsampling routines then aliasing can happen 
there too. There are ways to avoid that. Lanczos 
downsampling shows the effect less for example. Using a high 
quality printer setting requires a higher native resolution 
and the chance your data is downsampled is less likely.

There's another issue with grain and pixels: to the eye both 
grain and pixels have the tonal information and they 
interfere with one another. For example sharpening will 
increase general contrast much more in a digital image with 
grain than one without grain, the other way around a general 
contrast change will increase grain. If the software applies 
a smart print sharpening on the fly when printing, grain 
will become more visible and contrast increases.


-- 
Met vriendelijke groeten, Ernst


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