D-76@ 20C, stop and fix at 22C. Sloppy?

[willy_boots]

<p>I was just wondering, when people say to keep all solutions the same temperature, would you call this sloppy? My apartment is reliably 22C, so I mix up my D-76 1:1 for 20C and then figure everything else is close enough. Whaddya think?</p>

[larrydressler]

<p>If you are talking stop and fixer then you are close enough. How is your wash water?</p>

[willy_boots]

<p>Wash water, so far I've been 'eyeballing' it to get it in the neighbourhood, but I haven't been testing it, should I? Hypo-clear and photoflo at room temp (22C) from the distilled water that's sitting around. I have this glass thermometer but it's a little slow to change temperatures. Can anybody recommend a thermometer that responds really quickly to small temperature changes? Would make things easier.</p>

[leicaglow]

<p>No. You're within range. I always use a water bath for all solutions to get them to the same temp, then go from there. In other words, don't worry about individual chemistry, worry about the water bath temp.</p>

[Fotohuis RoVo]

<p>Within 2 degrees this should not give any problem.<br>

Apart from good (old type) Mercury thermometers, you have some pretty good digital thermometers too. 0-100C +/- 0,5 or +/- 0,25.</p>

[willy_boots]

<p>Ok, maybe I should go with the water bath technique. I guess it would take a little while before all the solutions were at the same temperature, but once they're there then I should just keep a close eye on the temperature of the bath itself? What sort of method do you use to maintain the water bath temperature? I'm working on getting a really solid reliable system down so I can be scientific about this whole thing.</p>

[larrydressler]

<p>Turn your thermostat down a little. :)</p>

[User_5888660]

<p>If your apartment is "reliably at 22C", why not just process the film at 22C? There is nothing magical about 20C. Check out the "time/temperature" chart on the massive development chart site. Freestyle also has a chart on its website. </p>

[willy_boots]

<p>oh, there's a temperature chart???? Ooooooohhhhh.</p>

[thirteenthumbs]

<p>IMO, yes. I routinely maintain ± .5⁰F/?C up to room temperature exceeding developing temperature by 10⁰F/5⁰C, but that is me.</p>

<p>Most if not all manufacturers print a conversion table to determine processing time at other temperatures. 68⁰F/20⁰C is considered the optimal development temperature but 65⁰F/18⁰C to 75⁰F/23.8⁰ is usable with higher temperatures giving more grain with most developers.</p>

<p>Adding a few cubes of ice to the tempering bath during the processing session helps keep the tempering bath temperature constant. Putting the chemicals in sealed containers in the refrigerator 30 minutes to an hour prior to processing then transferring to the tempering bath works well also.</p>

[jpo3136b]

<p>As long as you're not visibly busting and breaking the emulsion with a reticulation failure (looks like orange peel), then you're OK. Bad temperatures would be something like running a developer hot, like 100F/37C, and then shocking the emulsion with a cold, like 68F/20C or below. The film is built to be tough. All the hard work was done by the engineers in advance.</p>

[randy_boren1]

<p>I've seen reticulation with as little as a 5 degree F difference between dev and fix. It depends on the particular film. If you keep the dev, stop, fix within 2-3 degrees you shouldn't have a problem and if you are using a hardening fix then your wash water can be 5-8 off without any harm. I rarely process at temps above 75 degrees as this can cause other problems, too rapid initial development which can cause swirl marks, having a too short a dev time which can cause a timing issue, a change in contrast, etc. Temps above 80 degree greatly increase the chance of emulison damage. Modern films are much better at preventing reticulation but you should still keep the temps as close a possible.</p>