U of S | Mailing List Archive | alt-photo-process-l | Re: Photopolymer Plate Options

Re: Photopolymer Plate Options



Hi Chris,

I'm using 80% density, 1800 dpi stochastic.  It's all in my procedure online at http://www.lytescapes.com/procedures/polymer_photogravure.html

Some people who use my procedure also like 1200 dpi with the KM73 plates, and have found that works better for them.

Susan spoke with Copygraphics recently and apparently they're having Q/C issues producing the 1800 dpi screens.  They are comfortable doing the 1200 dpi screens, however.  Some kind of striations were appearing in the output of the 1800 dpi ones. 

Duane, the owner, is looking into the issue to see if their tech was not using the same procedure/software Peter Ellzy was using when he made mine originally.  It may also be a hardware issue with their Agfa Imagesetter.

In any case, any good service bureau with an imagesetter should be able to output the 80%, 1800 or 1200 dpi stochastic screen for you.

Susan, have you found another source for screens?

Thanks,
Jon

zphoto@montana.net wrote:
All of you doing solarplate,
what is the exact specifications of your imagesetter
aquatint screen so I can order one?
I am using the Welden one, and was wanting to try one from
Copygraphics as comparison.
Chris

----- Original Message Follows -----
From: Jon Lybrook <jon@terabear.com>
To: alt-photo-process-l@usask.ca
Subject: Re: Photopolymer Plate Options
Date: Fri, 16 Feb 2007 16:24:24 -0700

  
Hi Keith,

I actually learned the splash/scrub technique from Dan
Welden, but my  time in the drink is shorter.  I think he
now recommends 90 seconds.  35  is what seemed to work best
for me with my plates/screen/exposure  times/curve/light
source, etc. 

35 seconds might, of course, produce different results
under your  approach if you're using the standard aquatint
screen -- even if we're  using the same plates, etc.  I'm
sure you know this, but it seems  pertinent to mention it
here.

It's like an inverse domino effect.  Once the preferred
approach is  established, each parameter is related to all
the others by necessity to  get consistent results.  If one
is out of place or somehow different,  then only some of
the dominoes will fall:

___  ||||

:-o

And if you do decide to move one of the dominoes as an
experiment, other  ones must also be moved accordingly for
it to work in a similarly  consistent manner to your proven
and preferred approach.


___////

:-)

Jon

taylordow wrote:
    
Hi Chris,

I've never used a washout higher than 70-72 degrees with
either types  of plate, although I admit to extending the
time very occasionally  from 2 to anywhere up to 8mins.
No scientific reasoning going on here,  other than some
plates and exposures you can just <feel> need a little 
      
longer washout. Naturally, I'm curious to try Jon's times
    
of 35sec. I  tend to let the plates sit still in the
water for the first minute and  then gently scrub them in
a linear movement, rotating the plate 90  degrees each
time. Rinse with cold water and immediately blot with 
sheets of newsprint to remove excess water. 
I'm using an aquatint screen that I got through Dan
Weldon. 
Keith.

On 2/16/07, Christina Z. Anderson <zphoto@montana.net>
wrote: 
      
Jon, Nancy,  Keith, etc. etc.

          
".............  I also notice that 100 degree washout
for 5-10mn is recommended whereas solarplate requires
        
68-78 for 2 mn. " 

      

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Photography Option Coordinator
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College of Arts and Architecture
Department of Media and Theatre Arts, Room 220
P.O. Box 173350
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