Printing...do you use a stop with TF-4?

[PVia]

Hi all...

I know the bottle says no need for a stop bath, but I was wondering if that was OK. It makes sense because the TF-4 is alkaline, so a stop would be fouling the fixer with acid, but would the development be arrested by just throwing the print in the fixer?

This would definitely give me a bit of room on my small darkroom table to allow 2-bath fixing. So far, I've been using it with a stop...

 

[jim appleyard]

Hi all...

I know the bottle says no need for a stop bath, but I was wondering if that was OK. It makes sense because the TF-4 is alkaline, so a stop would be fouling the fixer with acid, but would the development be arrested by just throwing the print in the fixer?

This would definitely give me a bit of room on my small darkroom table to allow 2-bath fixing. So far, I've been using it with a stop...

I'm no chemist, but I don't use a stop bath, IMO, it would shorten the life of an alkaline fixer. Stop bath is another chemical I have to buy, even if it is grocery store vinegar. I just use a water rinse.

There is carry-over of developer to the fix if no stop, acid or water, is used, and yes, fixer arrests development, but there is speculation that this small amount of developer keeps the fixer from doing its job as effectively. I don't know how important this is, but it makes sense, especially as the build-up of dev increases.

 

[clay]

I think the speculation came about back when acid fixer was the only fixer to be had. The developer is alkaline, and carryover would slowly change the pH of the fix. With alkaline fixer such as TF-4, this particular worry is unfounded. FWIW, I never use stop either, but I always use TF-4 or on of the other alkaline fixers.

but there is speculation that this small amount of developer keeps the fixer from doing its job as effectively. I don't know how important this is, but it makes sense, especially as the build-up of dev increases.

 

[JBrunner]

Water, H20, the wet stuff. With certain developers and stocks, direct to fix can make pin holes in film. I slow it all down with a couple minutes of water stop. (not really a stop, it pretty much dilutes the developer away) I have fewer problems film processing over all using the water stop, and a presoak. If you are talking about printing, I use a two bath stop. IDK why you would feel the need for a two bath fix with something as good as TF-4.

 

[MikeSeb]

You only need one fixer bath with TF-4, and no stop. Just a water rinse. Any slight increase in development because you're no longer abruptly screeching to a halt with vinegar will be negligible.

TF-4 is great stuff. Simple is best.

 

[Photo Engineer]

TF-4 is very highly buffered. It can therefore be used with a stop without any significant harm being done to the fix. The buffer is the suspended solids you see in the concentrate, which dissolves when you dilute it.

PE

 

[DJGainer]

But, PE, even if the fix can withstand the stop, would the cycle of base dev, acid stop, base fix cause any issues? Would the benefit of the stop be outweighed by the effect of the shifts in pH during the process?

 

[Photo Engineer]

It has no effect. I have done it!

Having worked side-by-side with Bill Troop in the lab, I have heard no comment from him about this either, nor have I heard of any problems from Grant Haist who originated the idea. Grant and I worked together as well.

PE

 

[Dan Henderson]

When I switched to TF4 I stopped using stop bath (huh?)...anyway, I go from developer to a 30 second water rinse, to the TF4. Since I use the exact same process for test strips, pilot prints, and final prints, any increased development by not using stop bath is accounted for by the visual inspection at each stage, and my prints are never darker than intended.

 

[Thomas Bertilsson]

I have used TF-4 extensively in the past and all I can say is that it makes little difference whether you use acid stop or just water, as far as fixer capacity goes.
I switched to Ilford Hypam which is rather neutral pH and available around the corner when I need it. That switch had nothing to do with the quality of the fixer. They both do the job.
- Thomas

 

[Richard Jepsen]

I am a longtime user of TF-4 to reduce DR odor, improve workflow and toning. I toyed with the idea of using a weak stop; just in case. But what is the modern case for using a stop bath for prints?

J Lootens, On Photographic Enlarging and Print Quality (1967) recommends a stop bath when using an acid-hardener fix. Hardeners were required if drying on ferrotype plates. kodak/Ilford recommend stop baths to prevent stains and assist in preserving the typical acid fix. But today, I think we can avoid acid stops with film, and with more care, processing fiber prints.

 

[bruce terry]

Deep tray of water and 45 seconds of agitation is all the stopping TF-4 needs. Great stuff.

 

[dancqu]

... nor have I heard of any problems from Grant
Haist who originated the idea.PE

Clyde Hornacker is the original originator. It was in 1857,
a few years after it was found that sodium thiosulfate would
'fix out' silver halides, that he tested an alkaline fix and found
that it worked better. I don't recall the source so can not quote.

The story is he was treating a case of acid-indigestion and
spilled some bi-carbonate of soda in the fix. The alkaline
fix was born. Another one for Ripply's. Dan

 

[Photo Engineer]

Dan;

Thanks, I was referring to his entire publication of the idea and theory which kicked off Bill Troop's research which lead to TF-4. Of course others have worked on alkaline fixes. In fact, alkaline fixes were used by Kodak in X-Ray and in the P-122 process years before Haist published.

He was the one that explained the reasons for wanting an alkaline fix, namely increased swell and reduced wash times.

The fix came long before Hornacker IIRC. It was done by Sir Humphrey Davey due to his work on both photography and on thiosulfates:

Dead Link Removed

Hornacker had no clue as to what he had though if the reference is indeed correct. It took work in the mid 20th century to describe things properly.

PE

 

[dancqu]

Hornacker had no clue as to what he had though if
the reference is indeed correct. It took work in the
mid 20th century to describe things properly. PE

Perhaps there was a Mr. Hornacker and more did
test an alkaline fix some 100 years ago. If only he
had kept records and afterwards they been saved
and published. Then again film and papers
have changed. Dan