Can I use catechol developers for push processing ?

helios1014

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So I am considering adding either pyrocat had, hypocat, or obsidian aqua in my darkroom process. Are any of these good for push processing? Also, has anyone noticed a difference between hypocat and obsidian aqua performance wise?
 

Anon Ymous

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Hypocat? Perhaps you meant Hypercat? But anyway, IMHO, any developer can be used for push processing, but some will give better results. I would start with a developer that gives as much true film speed as possible. Xtol is a good general purpose developer that usually gives a tad more speed and fine grain. I have used Pyrocat HD, but it seems to give lower film speed than a typical developer, so I'd say it's not ideal. 2/3 of a stop less or so.
 
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"Pyro" developers typically result in a LOSS of film speed, not a boost, so they're not good candidates for pushing film beyond it rated speed. Instead, look to a developer that is known for boosting film speed. I have found Crawley's FX 37 easily gives a half stop more speed with most film, and increasing development time will certainly give you more.
 
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Paul Howell

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MCM 100 utilizes both Catechol and P-phenylenediamine, I shoot at box speed with most film, Tmax 400, TriX, at 400 Foma at 320, so pushing might be doable, but due to long development times for high speeds films that run 18 to 22 minutes at 70 degrees F, adding 30% additional time for a one stop push might cause base fog. Due to cost, around $48 a gallon, I have stopped using MCM 100. I shoot a lot of Tmax 400 at 800 at standard development times with only little loss of shadows detail, a true one stop push is 1600 with 30% in development time in HC 110, DK50 or D76.
 
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