Re: filmscanners: Sprintscan 120 and new negative proile scheme

[Julian Robinson <julian@austarmetro.com.au>]

At 23:07 08/06/01, you wrote:
>Do minilabs read the emulsion type before printing neg? No.

My lab once told me that my prints were not up to their usual excellence 
"because we haven't got the Supra profile right yet".  So I understand that 
minilabs DO use individual film profiles for some purpose.

That said I agree with Austin that this is not the best way to go for a 
scanner - for three reasons:

a) as Johnny said, emulsions change with bewildering rapidity, so even if 
you try hard you can be trapped without the correct profile.

b) as Austin said, the exposure and light source used when taking the photo 
etc must change the characteristics

c) films change from nominal characteristics before and after exposure - so 
there is no accurate reference anyway.  Changes start as soon as the film 
is out of the fridge, and fading can easily take a film a long way from the 
assumed profile.

The point of using profiles of course is to match the scanner's filter 
characteristics (or LED bandwidth) with the film response curves, and to 
remove the mask of a neg.  But there is an alternative, and that is for the 
scanner to do some kind of analysis of the film itself and attempt to 
automatically "profile" the film and hence produce a good automatic 
scan.  (which is what I thought minilabs did until the exchange quoted 
above).  This is what the Nikons do, by means which are beyond me, and IMHO 
they do it very well.  I have used only five film scanner/software 
combinations in my time, but the Nikon with Nikon ver 3 software is IME far 
and away the best at producing good default scans.  With ROC I imagine it 
is even better.

Julian

Julian Robinson
in usually sunny, smog free Canberra, Australia