U of S | Mailing List Archive | alt-photo-process-l | Re: solarplate images up on my website

Re: solarplate images up on my website



Christina Z. Anderson wrote:
One last thing: I found that using a colorized ink neg a la PDN vs a greyscale neg on the 2400 (all inks) produced better blacks. Who knows why that is.
Chris
I know David Hoptman uses greyscale 2880 dpi using all colored inks for his inkjet transparencies very successfully since moving from imagesetter transparencies to inkjet. I don't. I use black ink only currently.

I did a test early on comparing the two approaches (greyscale using color and greyscale using black ink only) and found the tones in the color/greyscale one to be much less accurate with the polymer plate I was using at the time (JetUSA I think was the brand). The results were extremely different, in fact. Kind of makes sense to me in this way: These plates are clearly more and less sensitive to different colors, but who, apart from the PDN users can tell us precisely what colors these are (I know Chris can).

If, when using all colors, a 30% grey contains, say, 9% red to create the grey, and the polymer plate happens to be more sensitive to red, that 30% grey is going to wind up being lighter than it would on the computer on your poly plate.
A pure PDN approach would inform the happy user what color most accurately blocks light on their particular plate after the testing is done. So it would be as predictable as all black and possibly more controllable.
I believe what I'm saying about greyscale/color transparencies is correct, but I'm not a PDN expert user...

Let me know what you think.

Jon