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Baisao
23-Feb-2016, 23:24
I need some assistance and I am hoping Sandy King might chime in. I am trying to use Pyrocat-HD (1:1:100) @ 21° in BTZS tubes to develop 4x5 FP4+. I am having tests done by The View Camera Store and the initial test for dilution is to develop for 4 minutes.

The problem is that the step wedge is too thin at 4 minutes using the above parameters. I barely have any density at step 11.

In addition to the above params, I used 60ml per tube and no presoak.

* If I am getting an exceptionally thin neg at 4 minutes, does it point to an error on my part or a characteristic of Pyrocat-HD?

* What is the best dilution and/or temp to use Pyrocat-HD with FP4+ in BTZS tubes?

Thank you,

Jim

SMBooth
24-Feb-2016, 00:20
On Sandys web site it states 8.5 min in rotary tubes/tanks for 1:!1:100 & pre wash.
http://www.pyrocat-hd.com/html/times.html

iml
24-Feb-2016, 01:36
4 minutes seems awfully short to me. I don't use tubes, but I give my 4x5 FP4+ 12.5 minutes in trays in Pyrocat HD 1:1:100 at 20 degrees C, and shoot it at ISO 100. I presoak for a couple of minutes, and agitate by gently rocking the tray 4 times every minute (I only process one sheet at a time, I like to be careful). Results are always good.

Steve Sherman
24-Feb-2016, 05:21
I need some assistance and I am hoping Sandy King might chime in. I am trying to use Pyrocat-HD (1:1:100) @ 21° in BTZS tubes to develop 4x5 FP4+. I am having tests done by The View Camera Store and the initial test for dilution is to develop for 4 minutes.

The problem is that the step wedge is too thin at 4 minutes using the above parameters. I barely have any density at step 11.

In addition to the above params, I used 60ml per tube and no presoak.

* If I am getting an exceptionally thin neg at 4 minutes, does it point to an error on my part or a characteristic of Pyrocat-HD?

* What is the best dilution and/or temp to use Pyrocat-HD with FP4+ in BTZS tubes?

Thank you,

Jim

I agree, 4 minutes is too short a time to ensure accuracy. My Fp4 in tubes is developed at 70 degrees at a dilutin of 5-3-800ml for a relatively low contrast highlight density, .9 - 1.0 above film base plus fog.

Would need more information on your process to offer an opinion

Cheers

Baisao
24-Feb-2016, 07:53
I agree that 4 minutes is too short to develop the negative, however this is an initial test to determine dilution, per Fred of the View Camera Store.

I'm curious to hear from people who use BTZS and what dilution they settled on.

sanking
24-Feb-2016, 08:56
I need some assistance and I am hoping Sandy King might chime in. I am trying to use Pyrocat-HD (1:1:100) @ 21° in BTZS tubes to develop 4x5 FP4+. I am having tests done by The View Camera Store and the initial test for dilution is to develop for 4 minutes.

The problem is that the step wedge is too thin at 4 minutes using the above parameters. I barely have any density at step 11.

In addition to the above params, I used 60ml per tube and no presoak.

* If I am getting an exceptionally thin neg at 4 minutes, does it point to an error on my part or a characteristic of Pyrocat-HD?

* What is the best dilution and/or temp to use Pyrocat-HD with FP4+ in BTZS tubes?

Thank you,

Jim


Jim,

For most applications (silver and scanning) I prefer the 1+1+100 dilution of Pyrocat for FP4+, 2+2+100 for most alternative processes.

For your BTZS tests I would run the tests at 5-8-12-16-20 minutes, I always pre-soak for 3-5 minutes with rotary processing. The shortest time should give a negative with very low contrast and somewhat less than full film speed.

Sandy

Baisao
24-Feb-2016, 09:40
Jim,

For most applications (silver and scanning) I prefer the 1+1+100 dilution of Pyrocat for FP4+, 2+2+100 for most alternative processes.

For your BTZS tests I would run the tests at 5-8-12-16-20 minutes, I always pre-soak for 3-5 minutes with rotary processing. The shortest time should give a negative with very low contrast and somewhat less than full film speed.

Sandy

Thank you for responding, Sandy. What temp would you suggest for those times?

Cheers!