Maybe..... I did 1+150 in testing Tech Pan films and you will find no difference (densitometer) 1 h or 2 h semi-stand. But a higher dilution is quicker oxydized. 1+100 is then maybe on the edge. So 1+50 will then certainly work till two hours.
I haven't found it to be exhausted in 40-50 minutes (20c), I've done 1+100 2 hour semi-stand
But on lower temperatures the process of oxydizing is also ran slower.
The difference for my Tri-X results between 1h and 2h was tremendous.
Originally Posted by RobertV
I'll put some 1+50, 1+100 and 1+200 rodinal in open air beakers tomorrow and do a timelapse video with my digital SLR, see how long it takes to oxidise.
Imo, it should be the film thats doing the majority of the oxidation, especially in stand or semi-stand.
Originally Posted by mablo
Please look at
my web page (in German), and the Rodinal article. Both are in German.
Strange idea, what if you started off at 24 degrees and let cool to 14 degrees? Pick a different starting temperature if necessary but you should have some serious developing action to begin and the cooling will not be as significant since while you end up at the same place, you just allow more action to begin with. 24 might be high, start with 22 or 23.
Once a photographer is convinced that the camera can lie and that, strictly speaking, the vast majority of photographs are "camera lies," inasmuch as they tell only part of a story or tell it in a distorted form, half the battle is won. Once he has conceded that photography is not a "naturalistic" medium of rendition and that striving for "naturalism" in a photograph is futile, he can turn his attention to using a camera to make more effective pictures.
Uwe, hast du mal einen Rodinal Test gemacht wie die Aktivität runter geht nach zirka 50 Minuten in einen Hochverdünnung?
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If you adjust the temperature adequately then your cold temperatures are no problem. Eder´s "Rezepte und Tabellen" (German book) says the original Rodinal´s temperature coefficient is 2. That means that if you lower the temperature by 10 degrees Celsius then you have to develop twice as long. To use your normal dilution and multiplicate by about 1.6 could be a good starting point for 14 C.
I developed in Rodinal at different temperatures, also at 14 C and everything was fine at every temperature. Unfortunately I don´t remember the time and dilution I took at 14 C. In contradiction to other opinions I found no optimum or especially good temperatur between 14 C and 20 C. Maybe somewhere over 20 C Rodinal becomes worse in grain, but I never tested that.
Lieber Robert, ich arbeite nicht mit Hochverdünnung. Aber man muss beachten, dass niedrige Temperaturen auch die Oxidation verlangsamen. Nach 20 Minuten bei 16° und 1+50 ist noch Aktivität da, aber bei weitem nicht mehr die volle.
Originally Posted by RobertV
That way you introduce a variable that is hard to control: the rate of cooling.
Originally Posted by Kevin Kehler
That's why i want to work at whatever the thermometer says (currently 14 C).
The alternative would be trying to keep the temperature up for an hour or so. Not having a heated, controlled water bath, i'd rather not.
It would appear that 14 C is not a problem, perhaps even a boon. So i'll go with that.
I will warm up the fixer though. Shouldn't be a problem, since that doesn't need to be kept at temperature for that long.
Originally Posted by piu58
I read your article (thanks, Folker!) and it removed all my worries. Thanks!
A few times I developed Fomapan 100 using Rodinal in my fridge, which I keep at 6 °C. The negs came out fine (I checked them now, for the sake of this post), with good density. The grain didn't become noticably much smaller, this is why I abandoned the idea, which was actually rather good, since there was no need to worry about controlling the temperature of the developing tank with the help of a water bath. I calculated the development time using an approximated thermal coefficient. Thanks Neelin for giving us the exact figure.
According to my notes, I used Rodinal at 1+25 and agitated normally.
Have fun with it!