how hot is too hot?

[ciaran_mcmenemy]

<p>Hi all, a quick question. What is the limit of the developer temperature that I can use without the film becoming damaged?<br>

I'm developing Tri-X as 1600, another as 3200, and I don't feel like spending half an hour sitting by the sink. <br>

thanks!</p>

[andrew_brown7]

<p>Hi,<br>

you could try the digitaltruth.com page. it has boxes you input film type, developer and temperature<br>

I typed this into google and got loads of info '''film development temperature chart'''</p>

[larrydressler]

<p>Here is a conversion chart. But much over 82F and you risk losing emulsion off the base with B&W film.<br>

http://www.digitaltruth.com/devchart.php?doc=timetemp</p>

[maris_rusis]

<p>You can go hot if you are careful.<br>

My favourite temperature for sheet film (one at a time) in trays is 32 Celcius = 90F. Hundreds of rolls of colour transparency film go through the E6 process every day at 37.8 Celcius = 100F. I've developed 35mm Tmax 400 at 45 Celcius = 113F with no problems. The key thing at higher temperatures is to ensure that nothing touches soft photographic emulsion except liquid and air. And avoid rapid changes in temperature which might cause reticulation.</p>

[glen_h]

<p>E6 and C41 hardened the emulsion to allow the higher temperatures.</p>

<p>As far as I know, B&W films also have harder emulsions than they used to have, but it isn't well documented.<br>

It looks like the Kodak data sheets still only go up to 75F, but the recommendations for the Versamat processor are at 80F. </p>

<p>http://www.kodak.com/global/en/professional/support/techPubs/f4017/f4017.pdf</p>

<p>gives times for EI1600 and EI3200 at 75F that aren't all that long. </p>

<p>You could try to fit it to Arrhenius and then predict higher temperatures. </p>

<p>https://en.wikipedia.org/wiki/Arrhenius_equation</p>

<p>Plot log(time) vs. 1/T and see if it is a straight line.</p>

[glen_h]

<p>See:</p>

<p>http://web.stanford.edu/~kaleeg/chem32/kin/</p>

<p> problem 11.</p>

[glen_h]

<p>When you plot ln(time) vs 1/T, the T should be in Kelvin ...</p>

[glen_h]

<p>The official chart for D76 has EI1600 at 6.5 minutes, and EI3200 at 7.5 minutes, so much less than half an hour at 75F. </p>

<p>As I noted, Kodak seems to allow at least to 80F but doesn't give times. Fit the function above and that should get you to 80F.</p>

[bethe_fisher]

<p>If you warm it it up to the point where the development is under about 6 minutes, you're going to start having problems with uneven development. Yes, it will take some time, but you won't be just standing around. Also, I've found that the Ilford wash sequence takes less time than constant running water wash. </p>

[sam_morris1]

<p>A two or three stop push isn't going to increase development times to half an hour, more like 15 min if using HC110 B, if I remember. And higher heat shouldn't effect the film, at least if you are thinking the emulsion will melt. I worked at a paper where we developed TriX in a mixture of D76 and Dektol which was heated in a tank to around 100 degrees. I think it took about a minute with constant agitation and resulted in a rather contrasty negative, but not unusable. And it allowed you to go from spooled negative to being in an enlarger in as little five minutes (1 minute developer, 1 minute rapid fix, 2 minute wash and squeegee film, find your frame, dry that frame with a hair dryer and get it in the enlarger).</p>