Stop bath

[Photo Engineer]

This fogging has happened to me. I do not have running water in my darkroom, and am using a three-slot processor with standing water in the middle (TF-4 at the end). Could I just dedicate the middle slot to another TF-4 bath and go straight from the developer to that first fix? What is the best setup for 3 slots using TF-4, or should I just go acidic and use stop bath?

You can use a stop bath with TF-4. I do it regularly.

Or, a running water rinse.

PE

 

[rwboyer]

You can use a stop bath with TF-4. I do it regularly.

Or, a running water rinse.

PE

Interesting - wonder why PF recommends against it?

Not that I am going back to acid stop or anything - just curious.

RB

 

[Photo Engineer]

PF is being conservative and wishes to preserve the pH against any changes. With an acid stop bath, and with the buffer in TF-4, the capacity and life will be reduced a tiny bit, and the wash times will go up a tiny bit. If you run regular tests for retained hypo and silver, there should be no problem.

PE

 

[cbphoto]

That's good news, PE! I wasn't sure how to solve this problem.

 

[rwboyer]

That's good news, PE! I wasn't sure how to solve this problem.

What developer are you using when you experience an issue? What dilution?

RB

 

[cbphoto]

Would using the stop before the TF-4 be preferable to using two TF-4 baths? Ignoring the economics of it, for a moment.

 

[cbphoto]

What developer are you using when you experience an issue? What dilution?

RB

LPD, near full strength (started 1:1, replenished with stock).

 

[rwboyer]

LPD, near full strength (started 1:1, replenished with stock).

I use standing water with sheet film only and have never seen the issue at all - I use a much more dilute developer though.

RB

 

[Photo Engineer]

Would using the stop before the TF-4 be preferable to using two TF-4 baths? Ignoring the economics of it, for a moment.

Without some sort of bath between the developer and fix you will probably have a problem. Running water or a stop are the only real alternatives.

Two fix baths after either of the above is better than one.

I use one though as I run continual tests on process quality.

PE

 

[rwboyer]

Would using the stop before the TF-4 be preferable to using two TF-4 baths? Ignoring the economics of it, for a moment.

I would guess it would exacerbate the fogging issue.

RB

 

[cbphoto]

Thanks, both. I'll grab some stop KISB tomorrow.

 

[WolfTales]

Thanks everyone. I'll grab some Heinz tonite.