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WayneStevenson
8-Apr-2014, 06:33
113505

I just thought I would share my results from testing some Ilford MGIV RC paper that I cut down into 4x5 to load into my cut film holders. With the intention of shooting at 8x10.

Besides Dektol and fixer, you need three other chemical solutions. Easily obtained, and inexpensive.

Bleach (2 part, mixed 1:1, makes very short life. I get several days before it stops working. It eventually goes clear but will still be useless with it's normal colour when it goes bad so always test):
Part A: 2g Potassium Permangnate to 1000ml water
Part B: 28g Sodium Bisulfate to 1000ml water

Clearing:
30g Sodium Metabisulfite to 1000ml water

Hypo Stock Solution:
32g Sodium Thiosulphate pentahydrate (Hypo) to 1000ml water

1)Developer Kodak Dektol stock with 3ml of hypo solution for 1:00 minute
2)Rinse
3)Bleach for about a minute
4)Rinse
5)Clearing solution for about a minute.
6)Rinse
7)Second exposure was done in daylight at sink while clearing and rinsing for only a couple minutes at most.
8)Second developer 20 - 30 seconds approx. Should be to completion.
9)Rinse
10)Fix (fixer of your choice)
11)Rinse
12)Dry.

Harold_4074
8-Apr-2014, 13:22
Interesting.

Years ago, I used to reversal-process Kodak Fine Grain Positive using a bleach/redevelop, but I don't recall ever seeing a formula for either which called for hypo in the developer. Is this your personal brew, or is there a resource of formulas like this somewhere?

I've often thought that a variable-contrast "film" would be interesting to play with (never mind the blue vs. green spectral response!) so it is interesting to know that VC paper behaves itself so well.

Thanks for posting!

WayneStevenson
8-Apr-2014, 17:34
The hypo addition was intended for film reversal to slow things down a bit (not my recipe). Things went pretty quick for me with regular Dektol that I added it as well. And it seems to work great.

I'd love to try this paper out with contrast grade filters as well. Heh.

Emmanuel BIGLER
10-Apr-2014, 08:39
Many thanks for sharing the recipe with us !

Regarding additives in Developer#1, I remember a recipe for B&W film reversal process recommended by MACO, where potassium thiocyanate was added "in order to dissolve silver salts" but I have no real idea of the actual mechanism.

I have found this page in German, for film reversal; "Kaliumrhodanid" is the same chemical as potassium thiocyanate.
http://www.fotografie-in-schwarz-weiss.de/sw-fotografie/wissen/88-umkehrentwickler.html

----

Regarding filtering for contrast management : ss far as I've discussed with pinhole aficionados here in France using paper negatives, they prefer to use grade 0 or 1; so the idea is to filter to a relatively low contrast for the VC paper, not high contrast. But I have no idea how this combines with the reversal process.

Do you have an approx idea of the ISO rating ? Of course this will change behind a filter, but at least a starting value would be very helpful.
Thanks again !

WayneStevenson
10-Apr-2014, 20:38
You're welcome. :D Thanks for that bit of info on dissolving silver salts.

Oh. So sorry for that. I didn't realize I left that bit of information out. I spot metered the large light log in the pile. Shot the paper at ISO 3.

Emmanuel BIGLER
11-Apr-2014, 02:27
Shot the paper at ISO 3.

Thanks !
That's not really a much slower photo-sensitive medium than MACO SLIDE-DIRCT direct-positive ortho film, a very special film used to make direct copy of B&W transparent material.
This kind of direct-positive film existed in the Kodak catalog in the good old days, and is l available from AGFA-Mortsel [cut to size by MACO, but today no longer available in 4x5" sheets]. This special film is processed in a regular paper or film developer, no reversal process needed.
Speaking about direct-positive material, since ILFORD-HARMAN has on catalog a direct-positive paper, it would be nice to see if the reversal process of regular B&W paper yields better results in terms of tonal range and contrast management than ILFORD-HARMAN direct-positive paper.

WayneStevenson
11-Apr-2014, 05:17
I'm interested myself. I never had the pleasure of shooting any. But the ISO for it was suggested to be around ISO 3 as well. It's a shame that Ilford Switzerland shut the factory down that was manufacturing it. Hope Ilford Photo finds a solution to have it made again.

gtmatias
23-May-2016, 10:54
113505

Clearing:
30g Sodium Metabisulfite to 1000ml water


Hello there,

Does it need to bem Sodium or potassium will do?

Thank you!

gtmatias
9-Jun-2016, 06:55
Hello,

Already done with success. Further investigation needed.

valotus
6-Aug-2016, 04:38
Hi!

I recently found this topic while I'm looking for solution to get paper base neutral. I'm using Ilford multigrade RC paper and doing reversal process with permanganate bleach and potassium metabisulphite wash. Have been doing this for several years more or less successfully, but now I have got problems with yellow-brownish tint on white areas.

I have tried to trace it in different steps of process, but the weirdest thing is that the stain mostly appears in last wash after fixing. Before that image seems to be neutral and if there is any slight colour, fixing will remove it. But then comes the ugly yellow-brownish stain...

Any help and hints are greatly appreciated.

J-P

Pere Casals
6-Aug-2016, 05:13
I just thought I would share my results from testing some Ilford MGIV RC paper t


Many thanks for sharing, I'll use your information to try it.

I'd like to ask at what ISO paper was exposed ?

Thanks in advance

Regards

valotus
14-Aug-2016, 03:17
I recently found this topic while I'm looking for solution to get paper base neutral. I'm using Ilford multigrade RC paper and doing reversal process with permanganate bleach and potassium metabisulphite wash. Have been doing this for several years more or less successfully, but now I have got problems with yellow-brownish tint on white areas.

I have tried to trace it in different steps of process, but the weirdest thing is that the stain mostly appears in last wash after fixing. Before that image seems to be neutral and if there is any slight colour, fixing will remove it. But then comes the ugly yellow-brownish stain...


I finally discovered (at least partial) solution to my problem. Don't know what mechanism makes it, but potassium metabisulphite wash was the reason which caused paper base colouring after process.

At first it was pretty confusing because as a wash it seems to work perfectly and totally removes all stains after permanganate bleach, leaving paper totally bright white. But as I told before, very unpleasant yellow tint will then appear after final development and fix.

Some years ago I used weak sodium hydroxide dilution as a wash, so I swapped back to it and got rid of colouration. What I stated confusing was that sodium hydroxide wash doesn't solve permanganate stains totally and will let paper pretty dirty looking, but this will be compensated in final developing which cleans it again. After fix and wash it stays clean and neutral too.

If someone is wondering why I am using this paper reversal process instead of traditional negative-positive method, this is the reason: :)

153823 153824 153825

Tin Can
14-Aug-2016, 05:04
Nice new Cabinet Cards.

Great work!

Rael
14-Aug-2016, 05:09
If someone is wondering why I am using this paper reversal process instead of traditional negative-positive method, this is the reason: :)

So you are doing this with a portable darkroom? Sort of a no-mess version of wet plate?

gtmatias
14-Aug-2016, 05:52
Hello,

after some test I concluded that 1.5 cand give me rather better results than 3 ISO.
Also, after seeing some other recipes for the bleach, I decided to use 2 minutes instead of one (If you wish, I will share the test image that I made to conclude that)


153830
This was the first test with 3 ISO (use exactly the recipe used suggested here)

153831
The last image with 1.5ISO


The reason for going down one stop is related with the fact that all images came a bit to dark (so the paper needed to be burned a bit more in the first exposure)

valotus
14-Aug-2016, 15:12
So you are doing this with a portable darkroom? Sort of a no-mess version of wet plate?

Actually it is pretty much like no-mess version of wet plate. I have had this museum project going on for several years and this is a perfect process for it; it's fast (with RC paper it can be done dry-to-dry and even mounted on cardboard within 20 minutes under primitive outdoor museum conditions), still it's a traditional silver based process.

Orthochromatic BW paper tonal range is pretty close to wet plate and any impurities of process just makes more old look to it. And maybe the best of all, final developing can be done on daylight, so everyone standing around my desk are able to see the magic of image appearing on paper... :)

Darkroom with safelight is only needed for the first developing/bleach/clear steps and also for loading plateholder, so it can be done in quite small or even portable darkroom.

ibabcock
22-Apr-2017, 04:43
I am just starting out with paper negatives, getting interested in positives.

I see permanganate bleach mentioned in this thread, and I see very nice photos on Flickr by dipositif who uses potassium dichromate with sulfuric acid as bleach. I am collecting tools for Bromoil, and so already have copper sulfate, potassium bromide, and potassium dichromate on hand.

My goal is to bleach and use sodium sulfide toner (like dipositif on Flickr). The question is, does it matter what bleach process I use??

I have Adorama paper but plan to get some Slavich Bromportrait 80 since it seems that the Brom papers give the most substantial toning result.

koraks
22-Apr-2017, 05:57
Try it out! I'd say it doesn't matter, but I've only experimented with dichromate bleach so far - and a bit with copper sulfate, but that wasn't aggressive enough to my taste, although in hindsight, it may work well for mordancage (but that's an entirely different can of worms).

As for sepia toning: I always use a thiourea sepia toning (if I want sepia that is), which works on every paper as far as I can tell. The extent of toning depends on how far you bleach back the image and the hue (varying from greenish yellow to warm brown) can be varied with the ratio of NaOH:thiourea.

sapata
16-Jan-2019, 14:57
113505

I just thought I would share my results from testing some Ilford MGIV RC paper that I cut down into 4x5 to load into my cut film holders. With the intention of shooting at 8x10.

Besides Dektol and fixer, you need three other chemical solutions. Easily obtained, and inexpensive.

Bleach (2 part, mixed 1:1, makes very short life. I get several days before it stops working. It eventually goes clear but will still be useless with it's normal colour when it goes bad so always test):
Part A: 2g Potassium Permangnate to 1000ml water
Part B: 28g Sodium Bisulfate to 1000ml water

Clearing:
30g Sodium Metabisulfite to 1000ml water

Hypo Stock Solution:
32g Sodium Thiosulphate pentahydrate (Hypo) to 1000ml water

1)Developer Kodak Dektol stock with 3ml of hypo solution for 1:00 minute
2)Rinse
3)Bleach for about a minute
4)Rinse
5)Clearing solution for about a minute.
6)Rinse
7)Second exposure was done in daylight at sink while clearing and rinsing for only a couple minutes at most.
8)Second developer 20 - 30 seconds approx. Should be to completion.
9)Rinse
10)Fix (fixer of your choice)
11)Rinse
12)Dry.

That's great!
I'm very curious about this process, specialy bacause it uses very few chemicals and as you've mentioned, easily to find.
Is there anything I have to look while developing? I mean... because it's made by inspection, do I have to pay attention to any particular stage of the process?
Also, at n.5 "clearing solution for about a minute" is this one minute done under the red safe light?
From n. 7, everything is made in normal light condition, correct?
Many thanks!

Tin Can
16-Jan-2019, 15:41
Wow, very cool!

Thanks for posting a complete process with specifics!

Pere Casals
16-Jan-2019, 15:58
From n. 7, everything is made in normal light condition, correct?


I guess you can make step 3) and beyond with lights open. For BW film reversal I do that.

sapata
16-Jan-2019, 19:07
I though I might have a go with potassium metabisulfite (which is the chemical I have) and didn't work. Everything turned black...I'll post the results when I buy the right chemicals ;)

gtmatias
17-Jan-2019, 00:22
I have tested some variables:
No rinse
Second light exposure step
Pre flash

No rinse: possible but shortens chemicals usability
Second exposure: from step 5
Pre-flash: helps with darker tones

I don't know about weaker second developer. The image gets more difficult to develop and black to appear.
Cheers
186511
186512

Pere Casals
17-Jan-2019, 03:03
I have tested some variables:
No rinse
Second light exposure step
Pre flash

No rinse: possible but shortens chemicals usability
Second exposure: from step 5
Pre-flash: helps with darker tones

I don't know about weaker second developer. The image gets more difficult to develop and black to appear.
Cheers
186511
186512

You should not avoid rinse... it's the single not harmful step.

First: do process lights open after rinsing out completely first developer, in this way you will see well what happens and if something fails.

>>> Check bleach bath works ok. Bleaching has to clear all black areas that 1st developer turned black, if after bleach you have black in the paper then bleaching was not good, mix fresh bleach or use another bleach.

You can develop a strip of paper with open lights to obtain a black thing, then rinse and bleach it, to see if bleach clear all black and converts it to a pure white strip.


>>> Paper has emulsion on it, the share of emulsion that has not been exposed&developed in the 1st development will turn black in the second development, if your result is too black then you can expose more or develop more in the first development (or less in the second). The more black you have after 1st development the less black you will have after the second development. 1st Development time may control contrast, so you have to balance exposure vs development time to control both average density and contrast. But use also a grade of paper to adjust contrast, if too much contrast use grade Soft (1)

>>> as a secondary control factor you may shorten the second development, to not develop all emulsion left by the bleach process. As you have lights opens you can decide when the paper is dark enough.

>>> With preflash, also make a "contol strip", don't make a preflash for all the sheet, but by moving the dark slide at 2cm intervals you get the effect for different preflash intensities.

You have to do 3 additional things: calibrate, calibrate and calibrate.

Get Beyond The Zone System book ($4) and learn how to calibrate film. From the spot metering in each scene spot and exposure you may predict what density (grey level) you will obtain in the paper.

If you use a sheet holder you can "slide inside" the dark slide at regular intervals, blocking light in an area on the paper to have different exposure times on the paper, so you have a test strip.

Let me encourage to insist in this, it would be rewarding when you obtain nice results with that, it's a unique process sporting an scarce resource: authenticity !

Please share your images !


PD: you can make the exposure "bracketing" with strips vertical in the sheet and the flash bracketing in the other sense, so you'll have a matrix of squares, you should shot a uniform scene with remarkable texture.

From a single shot you may find a good starting point.

sapata
17-Jan-2019, 04:59
Nice one... I'll get the chemicals needed. Thanks!

gtmatias
17-Jan-2019, 07:24
Peres Casal,

i've been testing using your formula to:
. better understand where things may get wrong
. get better control on contrast
. Get out some variables as "visual inspection"

As a secondary objective I would like to experiment using it as "à lá minute" system. So, I asked myself what would happen if I didn't rinse (avoiding steps and getting everything more portable to a small darkbox).
It shorely works. It has some problems:
more prone to contamination.
the chemicals get exhausted more quickly.

Either way, I would like to use, at least the rinse after first developing and after clearing bath.

Could a stop bath be used as rinse after first developer? What do you think?


I had some trouble with first developer some time ago:
When it was expired the image got really dark and some wave pattern appeard.
If it doesn't develop completelly, the image got much dark.

When I get some time, I'll use it again.

Pere Casals
17-Jan-2019, 07:58
So, I asked myself what would happen if I didn't rinse (avoiding steps and getting everything more portable to a small darkbox).

Nothing wrong to experiment, but if a rinse is in a processing then we should ask why it is specified before bypassing it. One thing it can happen is toxic gass generation from mixed chem, so we should have some care with that.





Could a stop bath be used as rinse after first developer? What do you think?


Yes, of course. See Darkroom Cookbook, Chapter 9:

While a running water bath will not stop development as rapidly as an acid stop bath, it
will slow it down to the point that the amount of residual development is insignificant. This
is because, depending on its strength, it takes an acid stop bath approximately 15 seconds to
halt development and a running water bath takes approximately 30 seconds. The difference
in the negative image could not be measured. If you are still not convinced consider that the
slight additional development will automatically be factored in when you run your film development
test.


So the single difference is that water stop bath takes 15 seconds more to stop development completely, this can be compensated by shortening development time by 5 or 6 seconds, perhaps.

If you agitate a bit in the water then it will stop as fast than with the acid stop bath, because pH goes neutral faster.

Acidic stop bath can be harmful in a number of ways: Fumes (if acetic concentrate) are not good for people, it can generate bubbles inside emulsion, and not all fixers are acidic, transporting acid to an alkaline fixer has no sense.

Nothing wrong if using an acidic stop bath, but a water bath is as good as the acidic one. If a chem manufacturer wants an acidic stop bath then he says it in the datasheet, for example Adox CMS 20 (with Adotech II) case says "After the development you MUST use an acidic stop bath before fixing. Do NOT use plain water.", see datasheet. But this is a very specific case.

In the other side C-41 and E-6 chem does not use an acidic stop bath after first developer, that is a BW developer. So...

Me, I use plain water except for CMS 20.

gtmatias
17-Jan-2019, 09:31
Toxic gases? Maybe.
The Chemicals may interact in other ways. Who knows!

Anyway, this process must always made in a well ventilated space (metabisulphite has a quite harsh gas)

Pere Casals
17-Jan-2019, 10:17
Toxic gases

http://www-ehs.ucsd.edu/lab/pdf/photoprocessing_mccann.pdf
If you search "gas" in that pdf you have a dozen of situations.

just we have to be careful with some chem...

I use dichromate for reversal, this one has to be handled with care.

WayneStevenson
31-Jan-2019, 20:40
Sorry I haven't checked in, in years. I'm coming back. Real soon. Have lots I want to play with. At any rate, I did document my experimentation on Flickr. For those of you wanting to see the progression that I had started with to the end that you seen as the original post, here's it is. :D

I believe throughout I have been shooting it at ISO 3. Colour tinting I have found is caused entirely from first development.

The thread is here: https://www.flickr.com/groups/1011045@N21/discuss/72157642870149194/


187116187117187118

Pere Casals
1-Feb-2019, 02:35
The thread is here: https://www.flickr.com/groups/1011045@N21/discuss/72157642870149194/


Your post "Bleach (2 part stock 1:1 makes very short shelf working):" was really useful to me in the past !!!!

Tin Can
1-Feb-2019, 07:12
Great work. Great link I just subscribed!

Thank you!


Sorry I haven't checked in, in years. I'm coming back. Real soon. Have lots I want to play with. At any rate, I did document my experimentation on Flickr. For those of you wanting to see the progression that I had started with to the end that you seen as the original post, here's it is. :D

I believe throughout I have been shooting it at ISO 3. Colour tinting I have found is caused entirely from first development.

The thread is here: https://www.flickr.com/groups/1011045@N21/discuss/72157642870149194/


187116187117187118

WayneStevenson
1-Feb-2019, 19:01
Your post "Bleach (2 part stock 1:1 makes very short shelf working):" was really useful to me in the past !!!!

Hahaha. The shelf life of it caught me by surprise. Luckily I caught on quick and didn't waste any time when my image was wonky. ;)

WayneStevenson
1-Feb-2019, 19:01
Great work. Great link I just subscribed!

Thank you!

:D Glad you guys are are enjoying and/or making use of my post.

Gary Beasley
10-Feb-2020, 20:29
Doing a little research on reversal processes and Ive seen clearing baths with sodium sulfite alone and baths with sodium metabisulfite. What would be the reason to pick one over the other?

gtmatias
12-Feb-2020, 15:37
Doing a little research on reversal processes and Ive seen clearing baths with sodium sulfite alone and baths with sodium metabisulfite. What would be the reason to pick one over the other?

Hello there,

metabisulfite was sooooo much cheap and easier to find around here.

I read that both do the same so...

I hope it helped.