U of S | Mailing List Archive | alt-photo-process-l | Re: more and more and more solarplate

Re: more and more and more solarplate

Keith and Jon,
Have you ever run a step wedge group side by side of different ratios of exposure times within your parameters to see how the tonal range is affected up and down the step wedge? For instance, if you do a 44/44 sec exposure, to do a step wedge at 10/78, 20/68, etc. etc...I have done this with different times of exposures, but not a bunch of same time of exposure. I know that Dan says the more the aquatint the darker the overall exposure, the less the aquatint the lighter, etc. etc. which I won't go into again because I am REALLY supposed to be packing, downloading my hard drive, going to the post office, and exposing one more solarplate all before I head off to the airport for Miami....

The reason I ask is that I find it odd that Diane Longely just gives the aquatint that 1 minute after the image exposure. Although she does say to vary this ratio to achieve the correct tonality of the image. But it seems as if she is giving a minimal exposure just to deal with open bite.

I got some good points out of her book to be sure. One was the fact of plate tone within the varying plates--solarplate having lots of plate tone and others having none. Then I went back and reread Keith Howard's tome and that also adds lots of info if you can weed out the Imagon differences. I am assuming he might be there at SPE, too--or maybe it was CAA I saw him at.

BTW I got no mottling yesterday with an image wherein I powdered the positive and not the plate. But I'm SURE it is purely luck. Howard says emphatically under NO circumstances use UVBL light with this process. Put me in my place, as I limp along.

Scott Weber, I'll see you at SPE. Thanks for the tip on Marguilies.
----- Original Message ----- From: "taylordow" <taylordow@sprintmail.com>
To: <alt-photo-process-l@usask.ca>
Sent: Thursday, March 08, 2007 2:05 PM
Subject: Re: more and more and more solarplate


The exposure times are very close to what Jon suggests, 10-11secs for a 5K lightsource. This is much less than I would have usually have exposed the plate for (45secs). From the very quick test I ran, there is definitely a deeper black although the midtones don't seem to have shifted at all. With such a short exposure/washout, I was worried that it might be uneven but it's actually very uniform, even in a smooth grey sky.

I have never liked deep blacks or stark whites in my work, preferring some tone in the highlights, and detail that you have to look for in the shadows; the km73s give you that plate tone in the highlights. But with Jon's method I may have to be careful, for the blacks are so deep.

As I mentioned before, I've played with numerous combinations of screen and image exposures and every time, the best was always 50:50 (+or- 10%).


On Mar 8, 2007, at 9:40 AM, Christina Z. Anderson wrote:

What effect did you notice with shorter washout?

Longley exposes the positive on KM73 for about 3 minutes (2.5 in summer sun) and then the aquatint on top for 1 minute. I find that an interesting combo of times...