B/W negative reversal for Ilford films

[Ian Grant]

Originally Posted by dr5chrome

I would not suggest permanganate bleach. Not only is this agent explosive, it does not provide the best image quality. The bleach will leave deposits on the film if you use poor quality water, bleach agent or Sulfuric.

Rodinal, if it has p-amimo hydrochloride in it [the new version i think does not] is actually a very good agent to use in reversal processing, a very nice image quality but very expensive.[/url]

Perhaps a bit over-dramatic on the reasons not to use the permanganate bleach, used properly and fresh the image quality is excellent. It's obviously not suitable for machine use, but it's fine for small scale processing hence the reason it's been recommended for years by many film manufacturers.

As to Rodinal there isn't a "new version" only the name of the manufacturer has changed, from Agfa to A&O, it's still the same formula made on the same production line.

Ian

[Alessandro Serrao]

Originally Posted by Ian Grant

Perhaps a bit over-dramatic on the reasons not to use the permanganate bleach, used properly and fresh the image quality is excellent. It's obviously not suitable for machine use, but it's fine for small scale processing hence the reason it's been recommended for years by many film manufacturers.

As to Rodinal there isn't a "new version" only the name of the manufacturer has changed, from Agfa to A&O, it's still the same formula made on the same production line.

Ian

Infact, I'm using 250mg permanganate tablets sold commonly in pharmacies.
I didn't know that pharmacies would sell explosive materials...

The permanganate per se is not explosive, it's the Mn2O7 that is explosive.
Though it's a powerful oxidizing agent but it's not carcinogenic, as the dichromate is.

DO NOT USE permanganate with HCl 'cause you'll get chlorine gas.
DO NOT USE permanganate with *highly concentrated* H2SO4 acid, 'cause you'll get Mn2O7 which, as said above, is explosive and also O3 which can start a combustion itself if near alcohols.

In our bleach, if I've understood correctly, the first reaction is (qualitatively, I've not sechiometrically balanced it):
KMnO4 + H2SO4 --> MnSO4 + K2SO4 + H2O + O3 (gas)
and that accounts for the increased pressure in the developing tank when you open it after the bleach phase;
plus another reaction takes place: MnSO4 is reduced to MnO2.

[amuderick]

Thank you all for your advice. I have designed a few experimental formulas and will post my results.

One last question: I saw somewhere "Do not use stainless steel reels or tanks" in regards to B&W reversal processing. Is this true? Under what conditions?

[dr5chrome]

..that is your opinion, and you are welcome to it. I didnt say dont use it, I said 'suggest'.

I "heard" from unverified sources @ A&O that they infact are not using pAminophenal hydroChloride, which is the main developer in Rodinal. Thats just what i heard, take it or leave it.

regards

dw

Originally Posted by Ian Grant

Perhaps a bit over-dramatic on the reasons not to use the permanganate bleach, used properly and fresh the image quality is excellent. It's obviously not suitable for machine use, but it's fine for small scale processing hence the reason it's been recommended for years by many film manufacturers.

As to Rodinal there isn't a "new version" only the name of the manufacturer has changed, from Agfa to A&O, it's still the same formula made on the same production line.

Ian

[Ian Grant]

Originally Posted by dr5chrome

I "heard" from unverified sources @ A&O that they infact are not using pAminophenal hydroChloride, which is the main developer in Rodinal. Thats just what i heard, take it or leave it.
dw

Agfa's data sheets & MSDS have not shown Rodinal as specifically containing p-aminophenol hydrochloride for quite a number of years now, and A&O's current MSDS lists the same chemicals as before.

The A&O Rodinal product is still a p-aminohenol developer, and identical to the Rodinal produced by Agfa for at least the past 15-20 years.

Ian

[Alessandro Serrao]

Originally Posted by amuderick

Thank you all for your advice. I have designed a few experimental formulas and will post my results.

One last question: I saw somewhere "Do not use stainless steel reels or tanks" in regards to B&W reversal processing. Is this true? Under what conditions?

Mainly because the sulphuric acid will corrode the stainless steel.

[amuderick]

Gotcha. And since sodium bisulfate becomes a sulfuric acid equivalent in solution, a formula using bisulfate will also corrode the stainless steel correct?

Looks like I'm going to need to find a plastic reel and tank...

[Hans Borjes]

Originally Posted by Jermband

I'm trying to find out if Photographer Formulary's Reversal process for TMAX will work for Ilford FP4 125 or Delta 400, and if not, are there any other reversal processes out there?

Yes, there are other processes, e.g.
http://home.snafu.de/jens.osbahr/pho...r_reversal.pdf

If you have more questions, feel free to email me.

[amuderick]

Thank you all. I did successfully implement a reversal process. I'm not expert at it yet, but after some practice I expect excellent results. I think one can do a lot better than the TMax Reversal Kit and at much better cost.

I undertook this process with much interest. I reviewed the following information:

- the notes on this page
- your posts to Photo.net on the subject
- the discussions of ImageMaker and Julio1fer on the NelsonFoto forums
- the Ilford reversal recommendations
- posts by Alessandro Serrao on photo.net and apug.org
- posts on B&W reversal processing on apug.org
- lots of Wikipedia and other Google searches to help connect the dots and elucidate exactly what all of the chemicals do.

Below is my formula which I tested on 4×5 film using a Paterson Orbital Processor on Ilford HP5+ film.

All steps were subject to continuous agitation.

Temperature of all steps at 18C (64F). It is believed that lower temperatures reduce the toll that the permanganate bleach takes on the gelatin emulsion.

- FIRST DEVELOPMENT

6 tbsp Sodium Carbonate
15ml HC-110 (dilution B)
2g Potassium Bromide (optional)
500ml distilled water

2x Digital Truth recommended development time (to completion)

- FIRST WASH

Wash in distilled water, 15 seconds, empty
Wash in distilled water, 30 seconds, empty
Wash in distilled water, 60 seconds, empty

- BLEACH

A - 4g Potassium Permanganate
1L distilled water

B - 55g Sodium Bisulfate
1L distilled water

Mix A + B immediately before use

After 30 seconds lid can be removed. All additional steps can be in room light. Do not allow the film to be exposed to sunlight! Continue bleach for as long as it takes to remove all of the black silver image. Emulsion is extremely soft. Be careful in handling!

- SECOND WASH

Wash in distilled water, 15 seconds, empty
Wash in distilled water, 30 seconds, empty
Wash in distilled water, 60 seconds, empty

- CLEARING BATH

30g Sodium Metabisulfite
1L distilled water

Generates sulfur dioxide gas which can be irritating. Ventilate this step!

- THIRD WASH

Wash in distilled water, invert 5 times, empty
Wash in distilled water, invert 10 times, empty
Wash in distilled water, invert 20 times, empty

- CLEAR HIGHLIGHTS

10g Sodium Thiosulfate
1L distilled water

note: higher concentration will speed the process up to 50g / L

Agitate and inspect until highlights are just almost clear. This step sets your maximum ‘white value’. Should take between 0 and 20 minutes depending on solution’s concentration, the film, and EI

- SECOND EXPOSURE

Expose with 60-100W lamp at 1 foot distance for 1 1/2 minutes on each side

- SECOND DEVELOPMENT

1/2 - 1/4 strength FIRST DEVELOPMENT solution
Use 1.5x recommended development time by inspection until desired shadow density is reached. This step sets your maximum ‘black value’.

- FIX

5-10 minutes with hardening fixer inversion every 1 minute. You may not really need a fixer (if you’ve done the 2nd development to completion) but you do need a hardener. I use Kodak Hardening Fixer which does both.

- FOURTH WASH

Wash in running water for 10 minutes

- PHOTO FLO

1.25ml + 16oz water

- HANG AND DRY

Note 1: This film processor only uses 55ml of chemistry to develop four 4×5 sheets, 2 5×7 sheets, or 1 8×10 sheet. This is excellent economy. However, even at 4g / L of Potassium Permanganate, 55ml is not enough to bleach the film completely. For now I have extended this step to doing serial 5 minute bleaches until the pour-off is still purple (an indicator that the solution is NOT exhausted). I may experiment with a stronger bleach concentration.

Note 2: There is nothing magical about my wash technique. Use whatever means you are comfortable doing. I prefer using distilled throughout the process especially since it is only 55ml each time.

Others use tap. I like the consistency. I also mix all my solutions using distilled water for the same reason.

Note 3: The Paterson Orbital Processor is made with black plastic. After the silver from the first exposure is removed, you will still see a negative image because the black plastic is shining through the bleached areas. Lift the film and inspect in the light to make sure bleaching is complete.

Note 4: I chose permanganate bleach instead of dichromate bleach because, like many of us, I do my development in a bathroom used by all the members of my family. Permanganate is acutely toxic but dichromate is carcinogenic. I prefer obvious poisoning vs. lurking danger.

[dr5chrome]

Sounds like you've drawn your own conclusions. Thats what makes the darkroom fun. You've also picked a good film to start with.

dw