Overdeveloped, overstained PMK negatives

[Cor]

This is of course my personal opinion, but...I was never happy with PMK or it's incarnation Rollo Pyro for processing sheet film in a JOBO. I got excessive stain as well as a lot of B+F stain (afterbath with sodium metaborate, later I quit that step), resulting in flat negatives for VC printing and long exposures for UV processes.

Switching to Sandy's PyrocatHD cured all these problems. For 4*5 and 8*10 I use a JOBO (CPA2), For 4*5 I use special tank and 4*5 reel (2501n?), for 8*10 I use a paper drum in which one can put 2 sheets of 8*10 film, works like a charm, takes 600ml developer. Use the slowest rotation speed. I am happy with the JOBO no more messing with trays..

Best,

Cor

 

[Cor]

Oh, one more thing: it seems that you can (partially?) remove the Pyro stain: I quote from an old Email I saved:

>>>>>>>>>>>>>>>>>>>>>>>>

Here is the Kodak S6 formula for removing of stain:

Stock solution A:
Potassium parmanganate 5.2g
Cold water to make 1l

The permanganate has to be dissolved completely to avoid spots on the neg.

Stock solution B:
Cold water 500ml
Sodium chloride 75g
Sulfuric acid, conc. 16ml
Cold water to make 1l

Caution: Never put the water into the acid, it will boil up!

Stock solution C:
Sodium bisulfite,
1% soilution, this means 1g for 100ml water

1. Harden the film (2-3min) in a hardener solution like 5-10% glyoxal
2. Wash for 5min
3. Bleach in equal amounts of A and B for 3-4min,
the mix is of short shelf life
4. After bleaching put negative in solution C until
all stain is removed
5. Wash thoroughly
6. redevelop under 100W bulb in a non staining developer of low alkali
like D72 dilution 1:2. D76 does no good because of it´s high sulfite
and low alkali which would dissolve the silver image

I did use this formula successful with some overstained Pyro negs a couple
of times.
>>>>>>>>>>>>>>>>>>>>>>>

This is of course my personal opinion, but...I was never happy with PMK or it's incarnation Rollo Pyro for processing sheet film in a JOBO. I got excessive stain as well as a lot of B+F stain (afterbath with sodium metaborate, later I quit that step), resulting in flat negatives for VC printing and long exposures for UV processes.

Switching to Sandy's PyrocatHD cured all these problems. For 4*5 and 8*10 I use a JOBO (CPA2), For 4*5 I use special tank and 4*5 reel (2501n?), for 8*10 I use a paper drum in which one can put 2 sheets of 8*10 film, works like a charm, takes 600ml developer. Use the slowest rotation speed. I am happy with the JOBO no more messing with trays..

Best,

Cor

 

[frotog]

I recall how enchanted I was with my first pmk negs sometime in the early 90's. That was 35mm developed in Paterson tanks. Since moving to large format in 5x7 and 8x10 I have experienced many of the problems that other users have mentioned in this forum - streaking, mottled negs, overdeveloped edges in tray processing, the seemingly unavoidable fingerprints from film handling during dev. etc. I've tried a slosher tray, roto pyro, btzs tubes, rabbit feet, and prayer and each time I was lucky if I got a few flawless negs. I hear a lot of folks talking about pyrocat and its superior results to pmk but it's not the same thing - I was unable to get the incredibly smooth transitions between highlights (most notably in skys) that I see in a pmk neg. From my experience there are two ways of souping large format negs in pyro - both involve using a jobo 3000 series tank. The first entails filling the tank all the way with a water prewash and then inserting the sheets, put the lid on the tank, empty the prewash, fill tank with 2.5 ltr. of pmk, cork tank and hand roll. A bit of a pain, a lot of developer but good, consistent results. The second technique is even better and is a combination of G. Hutchings recommendation of a nitrogen feed through the jobo lift and Loose Gravel's technique (as spelled out in an earlier forum) of adding the "b" solution for 2' of agitation before adding the "a" solution. With the jobo at the lowest setting and the nitrogen feed regulated at a ltr./minute I'm able to develop six sheets at a time in one litre of developer and get flawless, perfectly even development (even with negs exposed n-2!). It's been a long time coming but totally worth it.

 

[dslater]

You could try processing single sheets in a rotary drum, dumping the developer halfway through the development time and replacing it with fresh developer with PMK or using something more suited to rotary development like Rollo Pyro or Pyrocat-HD.

That's exactly what I do when I use my Jobo for processing 4x5 sheets in a drum. Basically, I make up enough PMK so that I can change it every 4-6 minutes depending on how the total time divides up. So for my normal development time of 11 min, I use 2 batches for 5:30 each. If I wanted to develop for 12 minutes, then I'd use 3 batches of 4:00 min each. Another thing I do is to add 5ml of a 1% EDTA solution to each liter of mixed PMK - this prevents uneven development with the Jobo - althougn I think if you're using one of the expert drums with a CPP or CPA machine, you won't run into this problem. I have the CPE2 and use it with the 2509N reel which can have problems with uneven development.

 

[dslater]

I use 11x14" trays for 8x10". 16x20 is a very large tray for 8x10" negs, requiring an unnecessarily large volume of solution, particularly if you're developing with a one-shot pyro developer (I usually use ABC for 8x10" and larger). The problem is easily avoided in an 11x14" tray simply by developing more than one neg.

I can't really argue with you there about using a lot of chemistry - on the other hand, the way I view it is PMK Pyro is dirt cheap so I don't really worry about how much of it I'm using.

Of course in the 11x14 tray you could try changing your agitation method for a single sheet - instead of rocking the tray, you could just take the sheet out and drop it back in as if you were agitating multiple sheets. Do you think this would work?

 

[dslater]

Another approach to developing sheet film in trays is to set up two trays of developer and move each sheet from the first tray to the second. When you have moved all the sheets to the second tray reverse the process and continue this procedure back and forth until the end of the development time. PMK is so inexpensive that the cost of dev. for the second tray is negligible.

Hi Gary,
That's an interesting idea I hadn't thought of. Do you think this procedure would address the OP's problem with sticky negatives?

Dan

 

[garysamson]

Dan,
I have never had a problem with "sticky negatives" using this procedure, but as you know, I am a very patient photographer in the darkroom!
Gary

 

[dslater]

Dan,
I have never had a problem with "sticky negatives" using this procedure, but as you know, I am a very patient photographer in the darkroom!
Gary

Would you agree with my reply to the OP that he may be better off using a sodium metaborate solution for pre-wet instead of photo-flo?

Dan

 

[Tom Hoskinson]

I'm skeptical about using a metaborate solution as a pre-wet. I would run some tests first.

I know that plain water (no Photoflo or anything else added) is a sufficient pre-wet with ABC-Pyro and Pyrocat. I get excellent development uniformity, no streaking, low fog levels and the negs don't stick together.

 

[dslater]

I'm skeptical about using a metaborate solution as a pre-wet. I would run some tests first.

I know that plain water (no Photoflo or anything else added) is a sufficient pre-wet with ABC-Pyro and Pyrocat. I get excellent development uniformity, no streaking, low fog levels and the negs don't stick together.

Well - it is a recommendation straight out of Hutchings book. The alkaline environment causes the emulsion to swell and absorb more water more quickly.
Dan

 

[Tom Hoskinson]

Well - it is a recommendation straight out of Hutchings book. The alkaline environment causes the emulsion to swell and absorb more water more quickly.
Dan

Yes, I'm aware of that, but in my experience with ABC Pyro and Pyrocat, sufficient emulsion swelling and absorbtion takes place with a plain water prebath.

With the Metaborate solution, the emulsion is also absorbing an alkali (thus a development accelerator). I don't see any need or advantage to be gained from doing this.

 

[dslater]

With the Metaborate solution, the emulsion is also absorbing an alkali (thus a development accelerator). I don't see any need or advantage to be gained from doing this.

No more so than it already absorbs when it goes into the developer - the B solution is a Sodium Metaborate solution. By your argument, pre-wetting plain water slows the developer down a bit until the water is displaced by developer - in either case, I bet things come into equilibrium very quickly.

 

[dslater]

Yes, I'm aware of that, but in my experience with ABC Pyro and Pyrocat, sufficient emulsion swelling and absorbtion takes place with a plain water prebath.

With the Metaborate solution, the emulsion is also absorbing an alkali (thus a development accelerator). I don't see any need or advantage to be gained from doing this.

Hi Tom,
O.K. I'm at home and have just read the relevant paragraph. From The Book of Pyro third printing page 30:


"If the tap water for the presoak is somewhat acid, you may find that the films will stick when placed in the developer. A small amount of sodium metaborate (1/4 tsp.) dissolved in the presoak tray will eliminate the problem."

As you can see he only advocates using metaborate if your pre-soak water is acid. So you are also correct in that plain uncontaminated water is neutral Ph and should work just fine.

I see a couple of possibilities here - either Paul's (the OP) presoak water is acidic and photoflo doesn't change this or Paul's water is fine and the photoflo actually makes it acid.

Perhaps Paul should try using some distilled water for his presoak - that's what I always use.

Dan

 

[Tom Hoskinson]

Hi Tom,
O.K. I'm at home and have just read the relevant paragraph. From The Book of Pyro third printing page 30:


"If the tap water for the presoak is somewhat acid, you may find that the films will stick when placed in the developer. A small amount of sodium metaborate (1/4 tsp.) dissolved in the presoak tray will eliminate the problem."

As you can see he only advocates using metaborate if your pre-soak water is acid. So you are also correct in that plain uncontaminated water is neutral Ph and should work just fine.

I see a couple of possibilities here - either Paul's (the OP) presoak water is acidic and photoflo doesn't change this or Paul's water is fine and the photoflo actually makes it acid.

Perhaps Paul should try using some distilled water for his presoak - that's what I always use.

Dan[/QUOTE
Makes sense to me, Dan.

 

[DrPablo]

I can easily enough test the pH of my tap water.

I do find, though, that the negatives after presoaking in photoflo are fine for the first 5 minutes or so. I think photoflo is hydrophilic enough that it gets washed off as I agitate the negs during development. It's towards the end of development where they start to stick together.

 

[Andrew O'Neill]

The problem with the afterbath, whether it is used developer or a fresh metaborate solution, is that it merely increases B+F or general stain, not proportional stain.

This is so true. It is not a necessary step. I haven't used PMK since I switched to Sandy's Pyrocat-HD several years ago. I didn't like the greenish stain (I print mainly on VC paper).
Also, and I've said this several times on this forum, why not develop one sheet at a time. You have way more control and you will eliminate negatives that stick to each other, the potential for scratches and warming up the developer temperature with your fingers.

 

[Doremus Scudder]

I process 4x5 in PMK, not 8x10, but I have dealt with and overcome many of the problems addressed here. Possibly my methods will apply to 8x10 as well.

First, the pre-soak is necessary and it needs to be long enough. I develop on two continents; in Vienna, my tap water is alkaline enough that the negatives do not stick at all. In Oregon, my negatives will stick in the pre-soak if I do not leave sufficient time between them when immersing. (I haven't tried the bit of metaborate in the pre-soak, but I will...). At any rate, I now leave at least 10 seconds between negatives when immersing them in the pre-soak.

Do NOT use photo-flo in your pre soak. This is probably the cause of your negatives sticking together in the developer. You need all the surface tension you can get, and a surfactant, like a wetting agent destroys this.

Second, make sure the pre-soak is long enough; minimum two minutes with agitation. The emulsion needs to absorb as much water as possible before you transfer the negatives to the developer. Transferring too soon will cause them to stick. I shuffle negatives face-down from bottom to top (I recently switched from face-up to face-down and like it better). Go through the stack once every 30-40 seconds. If you can't shuffle that fast, develop fewer negatives at a time.

On to the developer. Agitation in PMK is tricky and needs to be done in a manner that ensures even exposure to the developer without excessive agitation, especially at the edges. Pushing the negatives to the bottom of a full tray rapidly just causes increased edge density due to the increased turbulence. It is important that the surface of the negative is evenly exposed to fresh developer solution regularly. It is not necessary to agitate vigorously.

I immerse the negatives in the developer one at a time, leaving 5 seconds between immersions. This ensures contact with the developer for long enough to prevent mottling. Lay the negative on the developer surface, face down, and submerge it slowly by pushing with the balls of the fingers on the back. I turn the first negative 180° from the others so that I can identify it easily by the position of the code notch.

When immersing the next negative, follow the same procedure, making sure not to push the negative down too fast. This ensures that there is maximum contact time between developer and negative.

After all negatives are submerged, agitate following the same procedure, going through the stack once every 30 seconds to begin with. I have found that agitating slower results in uneven development. Gentle submersion is the key to preventing extra edge density. I can only develop 6 negatives at a time and comfortably agitate this quickly. Six negatives equals one "flip" every five seconds.

After about 25% of the development time, I pick up the entire stack and turn it 180° and continue agitating as before. At halfway through the development, I switch to once through the stack every minute, tuning each negative 180° as I agitate. The slower agitation for the second part of the development helps edge and compensating effects. Agitating this slowly from the beginning, however, results in uneven development; hence the compromise.

Note that once through the stack every 30/60 seconds results in different interval times depending on the number of negatives you are developing. With two negatives, one agitation every 15/30 seconds suffices. With six negatives, every 5/10 seconds. When I develop only one negative, I agitate as if it were two. This if you agitate at the same interval for two negs as for six, you will give the smaller batch more development comparatively.

At the end of the development, gather the negatives together, making sure than negative number one is on the bottom. When the time is up, place the negatives in the stop bath, one every five seconds, starting with the bottom and working your way through the stack (just like the initial immersion in the developer). This ensures that all negatives receive the same development time. (I use a mild acid stop always. I have issues with both water stop and alkaline fixers that I won't go into here...)

Agitate in the stop, transfer to the fix, agitate (always in the same manner), rinse, wash, dry.

As far as fingerprints from the gloves are concerned. I have used both latex and nitrile gloves and never had a fingerprint problem except when the gloves were contaminated with fixer. It is surprisingly difficult to get the gloves clean. Wash, wash, wash them with soap and rinse well before handling negatives. If you unload holders with the gloves on (as I do) it is extremely important to do this and make sure the gloves are completely dry before touching the negatives. Developing face-down may help you reduce fingerprints as well. I believe that if your gloves are clean and you are not man-handling your negs, you will have no fingerprint problems. Make sure that you are not getting finger marks from loading/unloading with sweaty fingers, etc.

Once you have the agitation scheme down, adjust your exposure/developing time so your negatives are not too dense. Forget the after-bath as well.

PMK is worth the trouble, especially if you print on graded papers, as I do.

I hope this is helpful.

Best,

Doremus Scudder

www.DoremusScudder.com