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Old January 26th 04, 08:37 AM
Richard Knoppow
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Default Adjust B&W paper development time when using Uniroller?

(Phil Glaser) wrote in message . com...
Hi,

For the first time this evening I developed a B&W print in my
Uniroller drum on a motorized Uniroller base. I am using Ilford
Multigrade IV RC "Deluxe" with Ilford Multigrade developer. Having
never used a Uniroller before (and being unable to find directions for
B&W print processing with it on the web), I just followed the paper's
instructions for dish developing, using a dilution of 1:9 for one
minute.

This first print was a series of test exposures starting with 2
seconds at f/11. Now I realize that agitation and development time do
not affect paper in the same way as they do film, and that saying 2
seconds at f/11 is completely relative to the density of the negative.
Nonetheless, I was rather shocked to find that the the print came out
absolutely completely black -- absolutely nothing came through, not
even a hint of that 2 second exposure. So I experimented with the
development time for the uniroller, and found that if I developed for
only 20 seconds with constant drum agitation, I got relatively more of
normal image (normal given that I was still over exposing the print by
two stops -- see below).

Now this is all very disorienting to me (I feel as dizzy as I myself
were spinning in that drum!). I mean, it seems like I eventually got
an ok print when developing it for 20 seconds (the final exposure time
for this particular print turned out to be two stops less than where I
started, half the time, and down from f/11 to f/16). But I'm working
with a questionable negative, and am unsure if what I don't like about
the final print is the negative, or whether something about the print
process is mudying the print. Given my set up, I don't have a way of
developing in trays and comparing the results with what I'm getting
from the Uniroller.

I AM SO CONFUSED!!!

Is there a rule of thumb for print development time with a Uniroller?

Should I try working with the multigrad developer in a more diluted
form (ilford suggests 1:14 as an alternative to 1:9)?

And does anywone know where I can find information about using a
Uniroller for B&W processing on the web?

Thanks!

--Phil


This sounds like an exposure problem rather than a development
problem. The time of development in a Uniroller should be about the
same as time in a tray with constant agitation. The "normal"
developing time depends on the developer and paper but for an active
print developer, which this is development will be complete in about 2
minutes for fiber paper or RC paper without an incorporated developer,
or about one minute for RC paper with incorporated developer. Ilford,
AFAIK, is the only major company who makes RC paper without developer.
The developer is to allow the paper to be processed in rapid access
roller transport machines. In normal developer it causes the image to
appear quickly (perhaps 10 to 15 seconds) and to reach maximum in 60
to 90 seconds.
Exposure should be adjusted to achieve these development times.
Although some books recommend against compensating exposure by
changing development time some variation is possible in print
development. The time should not be shorter than about 45 seconds for
any paper because it will result in uneven development and poor
blacks. Probably one minute is the minimum for any paper. Stronger
developer does not change the required time very much. Even with
Dektol stock paper should take 45 seconds or so to give a decent
image. This is because prints are developed to reach maximum black
rather than a specified contrast index as is film.
What kind of enlarger are you using. If its not a color head type
what filter are you using? Note that the speed of variable contrast
paper without a filter is twice what it is with the filter. If you are
using a color head and still get overly short times try adding some
yellow to get a neutral density effect.
Desirable times for other than production printing are around 20
seconds, or longer if you must do any burning or dodging. Most
enlarging lenses have their best performance around f/11. I am really
curious about the enlarger because I think this is the source of the
problem.

Richard Knoppow
Los Angeles, CA, USA