P3D Re: Grain! (PHOTO-3D digest 3475)

[bobh@xxxxxxxxxxxxxxxxxx]

RE: Mark Shields says "Yes, slide film. The heavier and denser the 
layers of emulsion are, the more layers of grain there will be."
 This sounds logical thinking of silver image..BUT it is wrong!!! Slide 
film does not have 'grain' for the following reasons.
 1. Original silver recording image (a negative) is all three layers of 
color sensitivity is retained for second exposure and redevelopment.
 2. On redevelopment dye image develops alongside of second 
silver image (now a positive) (or in Kodachome with three 
exposures and developments). Silver image is then bleached out!!!
 3.What may appear to be grain is really spaces left  by silver grain 
or dye packets (which Kodachome does not have.)
 4. Each layer is unique, so spaces do not line up hence less 'grain 
effect' that a signular silver image. 
  A color negative onto color paper is very grainless and the Ilford 
XP-1 and XP-2 (colorless dye image..i.e b&w) gets finer grained     
in the print the more overexposed and desenser the layers for this 
very reason.  BobH
Bob Howard (bobh@xxxxxxxxxxxxxxxxxx)
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