Re: Film Length vs Dev. Time

"HypoBob" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> OK, confession time.  I went back and looked at my
exposure notes and
> found that the subject for the frames I was examining was
of high contrast.
>
> However, for a normal contrast landscape, the negative
contrast was
> still nearly one grade higher in the 7-frame clip than I
usually get
> with a full roll.
>
> The test was 35 mm TMX in Xtol 1+1 in a typical stainless
steel tank
> that was about 3/4 full of developer.  There were two
reels in the tank,
> and the agitation was 5 inversions every 30 seconds.  I
have always done
> very vigorous inversions with Xtol because I read
somewhere (probably in
> this ng) that Xtol 'likes' energetic agitation.
>
> Thanks for all the comments and suggestions.  They will be
useful as I
> continue this test.  So far, the TMX looks very good in
Rodinal 1:100.
>  (Agitated two gentle inversions every minute.)  There is
a noticeable
> graininess in smooth mid-tones, but the prints have a
slight edge in
> sharpness, and the midtone contrast seems a little higher.
>
> Bob
>
  Snipping...
  I think perhaps the agitation was too vigorous. A two reel
tank should hold 16 ounces of developer which is plenty for
a 36 exposure length of 35mm film. I don't think Xtol needs
any more vigorous agitation than other developers. The fact
that the tank was not filled suggests also that the
developer could slosh inside it producing a lot of local
turbulance and consequent uneveness of development. I think
if you do this test again using a filled tank and normal
agitation the clip test and full roll will come out much
closer if not the same. I use whatever the manufacturer
specifies for agitation. Kodak recommends 5 seconds every 30
seconds with at least three inversions in that time, Ilford
recommends 10 seconds every minute with no recomendation of
number of inversions. I follow this depending on the film
being used and find little difference between them.
  I develop 35mm film in Nikor tanks. Sometimes single rolls
in an 8 ounce tank, sometimes two rolls in a 16 ounce tank
and occasionally four rolls in a 32oz tank. This comes out
to the same amount of developer per roll. I get contrast
reasonably close to the developing chart contrast this way.
I use mostly D-76 diluted 1:1 for most films, Rodinal
occasionally for sheet film. My taste runs to fine grain
rather than acutance so I am biased in my choice of
developers. Diluted Rodinal is pretty reliable for good
acutance without having problems.


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Richard Knoppow
Los Angeles, CA, USA
[EMAIL PROTECTED]