Pyrocat-HD: Changing The Ratio Of Part A To B

thronobulax

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I've done a bunch of semistand development with Pyrocat-HD using the proportions of 1.5:1:200,250, or 300.

I am curious for those of you doing more traditional agitation, have you departed from the normal 1:1:100 proportions and, if so, why?

My understanding is that increasing the amount of Part B raises alkalinity and thereby makes development more aggressive. I am less clear what fiddling the amount of Part A would do.
 
If you change from 1+1+100 to 2+2+100, then you get more grain. Not obvious in large format, but noticable in 35mm. I deliberately used to use it that way when I liked a bit of grain in 35mm.
Shortens the development time too.
 
When i started using Pyrocat HD in rotary tanks on the Jobo, i had to increase the ratio to 2:2:100 to avoid oxidation problems that the Expert tanks displayed.

Mike
 
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