What dilution did you use for the ammonium dichromate? If you use it too
strong you will get excessive contrast and graining as well: for a
modest contrast gain a single drop of 2% is good for an 8x10 print.
Overall, I find very dilute a.d. is a far superior contrasting agent to
the pot. chlor. in the #2 solution for Zia, but a drop of 20% solution
will send any proper negative through the roof.
If the contrast was correct, but the print was grainy, then I suspect
you may have hit the wall on the printer's imaging ability. You may
simply be resolving the digital artifacts of the negative.
>
> I'm using the Epson Backlight Film. Gives a max density of 5.7 (fb+f
> density is .38), if you limit the range to 2.2 or so you get a pretty
> straight line portion of the curve to work with. I'm concerned with
> compressing a digital tonality with a range of 255 to something much
> less to fit this curve though. I can work with 16 bits with Photoshop 5
> now, hopefully that will smooth it out.
What you want to do is use the PhotoShop controls like "curves" or--oh
heavens I've forgotten the name of the other one and I'm not at my
design computer--that massage the data rather than simply truncating it.
Never use the "brightness" or "contrast" controls, they just throw data
out the window. Use the histogram viewer to see whether you've kept most
of your data after manipulating the curve. If the histogram is "gappy"
and looks like a comb with missing teeth, you've probably lost too much
data for smooth output.
>
> The density range and full Epson 1440 dpi resolution is there for sure,
> wether things less easily measured and quantified will hold up is
> another question.
1440 is enough for "sharp" results, but inadequate to carry the data
needed to portray smooth tonal progressions. Take a look at Dave Fokos'
excellent treatment of this subject to get an idea what you can
reasonably expect from the Epson.
---Carl