reverse processing APX 100

[rob3rt5]

I'm interested in reverse processing APX 100 using Rodinal Special. I'd like to do two reversals and thereby dissolve all grain. Is this possible? Which chemicals, times etc for APX 100 in RS? Thank you in advance for your replies.

 

[rob3rt5]

The reason I want to dissolve all the grain is so that I can enlarge my 35mm to much larger sizes and have clean whites and blacks.

 

[Nicholas Lindan]

Two reversals will certainly 'dissolve all the grain'. Unfortunately, it is the silver grains that make the image, and when you dissolve all the silver grain you will be left with clear, albeit grainless, film. Look at the quote just to the right of the big 'APUG' logo at the top of the page.

If you want to reduce grain then APX100 and Rodinal are a very poor choice. Try Kodak Tmax-100 developed in Microdol-X if you want to stick to your present camera and conventional films.

If you want even less grain then get hold of some TechPan and Technidol on ebay. And, of course, the obvious way to reduce grain is to shoot medium or large format.

 

[nick mulder]

Pyro/staining developers maybe ?

 

[Ian Grant]

If you want to reduce grain then APX100 and Rodinal are a very poor choice. Try Kodak Tmax-100 developed in Microdol-X if you want to stick to your present camera and conventional films.

The OP didn't say Rodinal

Rodinal Special is a totally different developer. Anyway the Rodinal & APX100 combination gives excellent fine grain, so would be an excellent choice.

In reversal processing the two developers are often not fine grain, but more akin to or can be print developers but the proces itself produces finer grain than conventional negative processing.

Ian

 

[Ian Grant]

I'm interested in reverse processing APX 100 using Rodinal Special. I'd like to do two reversals and thereby dissolve all grain. Is this possible? Which chemicals, times etc for APX 100 in RS? Thank you in advance for your replies.

Double reversal won't work, you can't differentiate between the processed silver after the 2nd development and the in soluble silver complex's formed during reversal bleaching, even if you could convert them back to halides their grain wouldn't be any finer on re-development.

Reversal B&W printing from a B&W transparency will give very much finer grain and great tonalitybut it's rarely if ever done as the controls needed are much more complex. I have seen prints made this way at a lecture back in the 70's by a PhD student who was researching the methodology, his images were stunning.

Ian

 

[dr5chrome]

..is there a reason you want to use APX? While APX can be reverse processed is is not one of the best films for this use. A better film would be DELTA100 or even PlusX if you want a traditional grain. APX is a good film but its design produces a poor dmax. I am not quite sure I understand what you are trying to accomplish.

regards

The reason I want to dissolve all the grain is so that I can enlarge my 35mm to much larger sizes and have clean whites and blacks.

 

[Tom Kershaw]

Reversal B&W printing from a B&W transparency will give very much finer grain and great tonalitybut it's rarely if ever done as the controls needed are much more complex. I have seen prints made this way at a lecture back in the 70's by a PhD student who was researching the methodology, his images were stunning.

Ian

Ian, could you give more details of this method?

Tom

 

[Ian Grant]

It's simple Tom, normal reversal processed slides are used in place of a negative, DIY dr5 Scala etc. Then you enlarge the transparency onto conventional B&W paper and reversal process that. I haven't done it myself from a B&W slide, but I've done it with colour slides onto B&W RC papers a couple of times, many years ago.

The huge issue is the length of wash sequence if you use Fibre based papers, what I saw back in the 70's was FB prints. RC papers are far easy, but washing the reversal bleach out of FB paper takes considerable time. It's not a difficult process just very time consuming

Ian

 

[Ian Grant]

Tom, I'd add that I use a similarish Dichromate bleach for toning FB papers nad it really does take a long time to was out of a print, when used with film of RC paper that time reduces very substantially. The bleach must be removed or it causes problems with the 2nd development.

Ian

 

[Tom Kershaw]

Why does the process give finer grain and better tonality? I'd have thought the disadvantages of positive - positive work would come to the fore, or is this what you mean by 'controls needed'?

Is the paper reversal process comparable to black & white film reversal using a light fogging step, and a Potassium Dichromate / Sulfuric acid bleach? Are there any alternatives to using sulfuric acid?

Tom

 

[Ian Grant]

Why does the process give finer grain and better tonality? I'd have thought the disadvantages of positive - positive work would come to the fore, or is this what you mean by 'controls needed'?
Tom

A variety of reasons, often alhough print type developers they use a silver solvent like Thiocyanate or Thiosulphate, which turns them into fine grain devs, also the initial silver image is removed and all the remaining silver halide is re-exposed, and given full development. That's a simple version

A reversal processed paper is capable of redering a longer tonal scale and better matching the reversed transparency.

Is the paper reversal process comparable to black & white film reversal using a light fogging step, and a Potassium Dichromate / Sulfuric acid bleach? Are there any alternatives to using sulfuric acid?
Tom

The reversal processing of paper is identical to reversal processing of B&W film. But obviously formulae may well need to be dpimised for the best results.

Some people don't use Sulphuric, I guess their alternative might work, you'd have to try it.

The only time I've seen or heard of the use of Reversal processing B&W film & paper to achieve B&W prints was while I was at University in the early 70's.

I saw the results, but the controls needed and the time per print makes it far less practical than conventioanl printing. I'd also like to see a print alongside a conventional print as I suspect that there maybe downsides to the Reversal/Reversal process, like loss of apparent sharpness.

Ian

Ian

 

[Anon Ymous]

(dumb question, but somebody has to ask)

Would it be ok to contact print a BW positive on ortho film and use the normal negative -> positive process afterwards? What will be lost?

 

[Tom Kershaw]

The only time I've seen or heard of the use of Reversal processing B&W film & paper to achieve B&W prints was while I was at University in the early 70's.

I saw the results, but the controls needed and the time per print makes it far less practical than conventioanl printing. I'd also like to see a print alongside a conventional print as I suspect that there maybe downsides to the Reversal/Reversal process, like loss of apparent sharpness.

Ian

Ian

It does seem like a very long way around to make a print.

Tom

 

[Ian Grant]

(dumb question, but somebody has to ask)

Would it be ok to contact print a BW positive on ortho film and use the normal negative -> positive process afterwards? What will be lost?

It was done the other way once, contact print a neg onto Fine Grain Positive. In dfact that's how Hollywood worked/works for B&W albeit with different films.

But if your going to make an inter-neg to print from then why not shoot negatives in the first place.

It does seem like a very long way around to make a print.

Tom

That's what I've always thought, and if you want the extra quality move up a format or 2, a lot less trouble. I just wouldn't have the time.

As soon as I settle and set up a new darkroom I will try the process though, as I'm still working on Reversal processing. Currently I can only print when in the UK.

Ian

 

[Anon Ymous]

It was done the other way once, contact print a neg onto Fine Grain Positive. In dfact that's how Hollywood worked/works for B&W albeit with different films.

But if your going to make an inter-neg to print from then why not shoot negatives in the first place....

Ian

Oh, that was pure curiosity, I'm pleased with the neg -> pos process

 

[rob3rt5]

I'm using APX 100 35mm because that's what I have a lot of. I'm just trying to clean up the negatives a bit more so I can make larger cleaner prints. Also I love the look of super clean whites. In essence, I'm trying to pull as much as I can from this film and the time it takes doesn't matter- the final results do. I'm looking to work the film not the paper.

 

[rob3rt5]

From what I understand dissolving the silver halide doesn't destroy the image because a latent image is left behind- just no grain. I thought if I didn't fix the image, I could reverse process again and diminish or dissolve the grain for the silver halide that was just exposed under a 100 watt bulb. Then, in theory at least, I would be left with a 35mm negative that is super clean. Any ideas?

 

[Ian Grant]

If it could be done it would be being used

The first image is processed and then bleached to a form of silver sulphate that does not redevelop during the second exposure/re-development. So you can't remove the second image without destroying the silver sulphate from the first. It's a no go.

Ian

 

[tim_bessell]

Just an off the wall idea. Use a staining developer as the second dev, then bleach the remove the sliver, hopefully there will be enough stain left to form a no grain image.

 

[rob3rt5]

Thank you all so much for your answers. I think I get it now. I can only reverse process once which will dissolve the silver in the whites(?) on the chrome that will be produced. Has anyone done this with APX 100?