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onnect17
9-Dec-2010, 20:15
Just ordered some Pyrocat-HD.
Looking for feedback and suggestions regarding its use as two bath developer.
Any way to control the shoulder/toe shape and lowering the F+B?
Thanks,
Armando

sanking
10-Dec-2010, 07:27
Just ordered some Pyrocat-HD.
Looking for feedback and suggestions regarding its use as two bath developer.
Any way to control the shoulder/toe shape and lowering the F+B?
Thanks,
Armando


Armando,

I have tested and used both Pyrocat-HD and -MC as two bath developers. One of the interesting results of two-bath development with these developers is that most films give a very straight line, with short toe and almost no shoulder. This is normally a very desirable feature that we would not want to change. That said, I don't really know of any mechanism that will alter the straight line characteristic as it seems to be simply inherent with the mechanism of development in a true two-bath developer, i.e. one like Pyrocat, Diafine or Jay DeFehr's Hypercat. You do not get the straight line curve with two bath developers like divided D76 and divided D23 because with these developers the mechanism of development is different as there is some development that takes place in Solution A, and this continues in Solution B, whereas with the true two bath developers the film merely soaks up the reducer in Solution A, then the image develops immediately when you plop it into Solution B.

Sandy

onnect17
10-Dec-2010, 12:03
Sandy,

Thanks for the explanation. I think the stain is helping me with the scanning when the resolution gets near the grain size, acting as a aliasing agent. That's whay my interest.
I went back to the unblinkingeye article and read it again. It mentions the importance of using slow speed in the rotary processing to minimize the general stain and the role of the gelatin thickness.
So I'm guessing, the length and agitation of the pre-soak enters to play in the equation too, right?
Any other factor to minimize the general stain without reducing the image stain, let's say temperature?

Also, any suggestion regarding exposure for TMX, Across with the two bath development?

Armando

Ken Lee
10-Dec-2010, 12:44
There has been considerable discussion of Divided Pyrocat on this forum.

You can find links to these discussions - and others on Pyrocat in general - on this page: http://www.pyrocat-hd.com/

Look for "Divided Pyrocat"

onnect17
10-Dec-2010, 15:30
Thanks Ken,
I found most of the answers in one of the links: "Pyrocat-HD/-MC 2 Bath Developing... "