Hi,
from my experience and from what articles and data I have read,
developer exhaustion is not a big problem, Shel, you are not
dealing with exhaustion (after all, even the homeopathical amount
of developer - 10ml or less, which sticks to film in 2-bath
development, is sufficient to fulyl develop a film! The second bath
is only alkali!), but with getting enough developing agent in the
dilution. That's why Agfa-Gevaert recommends using at least 2.5ml
of stock rodinal with 1:100 dillution. Same is with Microphen,
where certain amount of stock solution is minimum too.
Although the chemical effect might be (IMHO is) different from
developing agent exhaustion (remember the 2-bath dev), the result
is still the same. Perhaps the original poster's problem lies with
not using enough developing agent in the dillution, at some
dillutions, some tanks are not large enough to hold enough liquid
for the developer dillution to have enough of 'stock' agent. In my
1250ml Jobo tank (older, 1000 series), I can't develop full 5 films
in microphen at anything else but 1+0 or 1+1 dillution, because
IIRC minimum stock solution of Microphen per film is 125ml.
Good light,
Frantisek
Wednesday, February 27, 2002, 3:17:06 PM, Shel wrote:
SB> Good morning!
SB> That's a good point, Aaron. I've been using more than the minimum
SB> amount of developer solution for so long that I don't even think about.
SB> For example, a single-reel Jobo tank uses 250ml of solution to cover the
SB> film, but the tank will actually hold quite a bit more, I use 400ml of
SB> solution. The two reel Jobo tank will use 485ml (465ml?) of solution to
SB> cover two rolls of film, but I use 650- 700ml. There are also times
SB> when using very dilute solutions, such as Rodinal at 1:100, where I'll
SB> develop one roll in a two-reel tank, using 600ml of solution.
SB> Aaron Reynolds wrote:
>>
>> I'm not Shel, but it sounds like you're exhausting the developer with
>> longer rolls in the tank. I would suggest perhaps using more developer
>> per roll, and going with the correct time for the 'hotter' development
>> you get with 24 exposure rolls, and then compare that to the results you
>> get with the longer time. My guess is that you'll find the film
>> developed for a shorter period with more developer in the tank will have
>> finer grain.
Good light,
Frantisek Vlcek
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