Fomapan 100 sheet film reversal - results much above average!

[eumenius]

Hello friends,

today I mastered a reversal processing of Fomapan 100 in 4x5 size. Well, the results I get are the same as with Ilford FP4+ reversal, according to Ilford protocols - the same average density (though a bit higher), the same super sharpness and contrast, the same beautiful long gradation in mid-tones. I used Ilford reversal protocol, with some differences - a bichromate bleach (work better, on my opinion), and 10 g of hypo per liter in !st developer. First development time is 5 minutes. If someone's interested, I will post the whole process. After setting it up, I plan to process much of my 4x5 BW film as a slide for latter scanning, because I didn't get yet a 4x5 enlarger

Zhenya

 

[Alicouscous]

Ilford gives a formula with 9.0 g from sodium thiocyanate in first developper , did you try this formula soon ?
I dont have good results with this, all the films i've tested give pictures with a bad grey fog . Could we see scans of your pictures ? i'm very interested

 

[Kobin]

4x5 reversal

Please, Zhenya, post the process. I don't have a LF enlarger, either. Thanks.

 

[Jordan]

Do you have any scans you can post?
BTW, I also found that I needed to reduce the quantity of hypo in the FD and use a dichromate bleach -- this is for FP4 Plus.

I have a whole mess of Fomapan 200 on the way that I hope to try reversal processing out with also.

 

[Alicouscous]

I also found that I needed to reduce the quantity of hypo in the FD

In the formula with thiocyanate, Ilford say to use 9.0g per liter, I only use 2.0g !
Me too i'm interested by the pictures ! are the slides easy to scan ?

 

[Fotohuis]

today I mastered a reversal processing of Fomapan 100 in 4x5 size

It seems to be that the deliveries to Russia (for 4X5" format, new) are quicker than to Germany and to the Netherlands.
We are still waiting for our Fomapan 100 4X5" films............. :confused:

Robert

 

[Alicouscous]

because it's dangerous ^^

 

[eumenius]

Hello friends,

I was too busy today, and as a result I forgot my notes in the lab - I'll bring them tomorrow and post my protocol as a whole. I'll try to ask some answers.

I find bichromate bleach to be stable almost forever, and making no black mud on everything it touches - quite unlike the permanganate-based bleach. And the results look to be more brilliant, at least in my eyes I am a professional chemist, so I can handle bichromate with ease - after all, we wash our flasks with a saturated bichromate solution in concentrated sulfuric acid! Also, bichromate hardens the emulsion nicely, minimizing the risk of friction damage during treatment.

I can't say much yet about scanning - I'll try to do it quite soon and post the results. But it should scan well, on my opinion.

The thiocyanate has no advantages over hypo, on my opinion - we just need a silver halide solvent, and why should I work with thiocyanate that doesn't keep as well as hypo does? In early days they used ammonia with autochrome plates, but it's too smelly for tray development

Bad gray fog can be accounted for some underdevelopment in 1st developer, and underexposure during shooting - the exposure should be very precise to get good slides, that's for sure. I use an incident meter (old Sekonic L-418) and rate Fomapan 100 as 90 with halogen light. One has to adjust the process to get the results wanted.

The Fomapan 100 in 4x5 is really new, I didn't believe to myself when bought it - maybe that's a "gray" export? Everything is possible in Russia, really.

I don't find long washes to be of any importance - a 1 min wash under running tap water is quite enough, and I also re-expose the film right in a tray with clearing bath. Works fine for me. More details tomorrow

Cheers,
Zhenya

 

[Fotohuis]

Everything is possible in Russia, really

OK, nice to hear that. We like some "flexibility" .

 

[Albert]

Hello,

I heard of a similar process where instead of a silver halide solvent in the developer a pre-exposure of the film is used. The density created by the pre-exposure will then be bleached away before the second developer. Does anybody here have experience with this?

I want to use the process for enlarging 35mm negetives for gum-bichromate printing. Up till now I've used internegatives but this way it is very difficult to get clean results.

Albert

 

[eumenius]

Hi Alessandro,

the manganese dioxide still forms somehow on the reels etc., with concentrations as indicated by Ilford, and I just don't like the permanganate as a matter of fact The orange color is better for me, at least the bichromate bleach allows for better visual control of my films. I can't advise anyone against permanganate, I just use whatever bleach I find more convenient Also I like the results, maybe that's my own opinion, but there you are - the permanganate bleach didn't give to me what I wanted, at least in my eyes.

The sulfuric acid - bichromate mix is as old as Universe, of course, but it works fine - especially when the chromium ions adsorbed by glass are rinsed out with EDTA solution after cleaning, before the final wash. It also work well when hot. Maybe in some countries the method is abandoned now, yes, but we in Russia like and use it - because, for example, the working solution keeps OK for months, and we change it when it turns green. The persulfate baths should be prepared right before use, of course, and it's a big wastage of H2SO4, too - we already feel guilty enough about our environment. The persulfate itself is expensive and has a limited shelf life, and we got large drums of bichromate in stock. So, I can't see any reason to switch to alkaline permanganate, or persulfuric acid - the bichromate stuff, chrompick as it's called here, works fine and burns the most nasty dirt from our glassware.

Regards,
Zhenya

First and foremost: the permanganate doesn't leave any residue, neither a black mud. What's this black mud?

The other thing: you say that you're a chemist. Then you should know that using the dichromate for cleaning up the lab glassware is an habit of almost 20/30 years ago and it's completely abandoned nowadays, because now it's used the ammonium persulfate with concentrated sulfuric acid (H.M.Stahr, L.Sigler, Anal. Chem., 54, 1456A, 1982).

 

[eumenius]

Alessandro,

the alternative methods of labware cleaning are good while they are not coupled with big expenses That's the question of a scientific school we'be been raised in - I just can't imagine my lab without chromic acid The risk of simple work in organic chemistry / biochemistry lab is much higher compared to bichromate risk, so it's okay for me. Why, I am working daily with highly radioactive iodine, and it's volatile - the bichromate does not fume, at least

Good work too,
Zhenya

Eumenius: I know many lab around the world still use the chromic acid. I wanted only to point out that there are alternatives methods (which have their pros and cons) available.
I just feel that the extra risk is not worth the candle. In my lab we use alternatives methods and we feel much better this way.
It's just my p.o.v.

Good work.

 

[Kobin]

The nuances of bench/lab practices escape me. On the other hand, your reversal protocol, Zhenya, promises all kinds of interesting revelations. What would those protocols be, exactly?

 

[Alicouscous]

Me too I'm waiting the revelations !
Actually I try to reverse differents films in a personnal process, it could be very interesting to compare the results and the process .

 

[eumenius]

The nuances of bench/lab practices escape me. On the other hand, your reversal protocol, Zhenya, promises all kinds of interesting revelations. What would those protocols be, exactly?

He-he, that's what I forgot to write, being lured out by the newest approaches in lab work

So, I take Fomapan 100 in sheet size. It's a good film for reversal, because it's not made on blue Roentgen film base. The slightly matted backside doesn't make any troubles, either. Expose it as ASA 100 with daylight, ASA 90 with halogen light.

The whole process I perform in trays - it's easier and safer, and I don't have any tanks for sheet film The temperature is one of your room, 20-22 Celsius. I can't say that the temperature is critical for the process - keep your 1st developer at 20-22 degrees, and it's okay.

1. First development - 5 minutes

Ilford P-Q Universal 1+5, with 10 g of hypo per liter. A constant agitation in first 30 sec, and 15 sec each minute. I find hypo to be a good halide solvent for the purpose, not worse than K thiocyanate - so I use hypo, because I just don't like KSCN

I use my own-mixed P-Q:

Sodium sulphite, anh. - 100 g
Potassium carbonate, anh. - 100 g
Hydroquinone - 31 g
Phenidone - 1.28 g
Potassium bromide - 5 g
Sodium hydroxide - 2 g
Water to 1 l.

Add hypo right before using the developer, as it doesn't keep. 100 ml is sufficient for 6 9x12 or 4x5 sheets.

2. Running tap water wash - 30 sec

3. Bleach - until your black image dissolves completely, maybe 45 sec

ORWO bichromate bleach:

Potassium bichromate - 10 g
Sulfuric acid, conc. - 10 ml
Water to 1 l.

Dissolve the salt first, and carefully pour in the acid, mixing well. Be careful with this solution, it can be harmful to eyes and skin. I don't touch it with fingers - in the dark I slide in the film to tray, move it a bit in and switch on a light on another table. At this time you should see your image and decide if it's worth of further processing Some experience will give you the feeling of right exposure. After all, the BW slide can always be reduced or intensified

4. Running tap water wash - 30 sec.

Take the film from bleach not by hand, please.

5. Clearing and re-exposure

Clearing bath:

Potassium metabisulfite - 25 g, water to 1 l.
Or sodium sulphite - 50 g, water to 1 l.

Take your tray with clearing bath and film in it under your table lamp, with 100W opal bulb in it. Switch the lamp on and expose your film under it (~30-40 cm distance) for 30 sec each side. Move the tray about to give even light to it. The image becomes creamy-yellow, not white, in this bath.

6. Running tap water wash - 30 sec.

7. Second development.

Ilford P-Q universal 1+9, without hypo (!!) - 5-7 minutes, longer time will do no harm either. The slides would appear "dark", but that's how they should be, don't worry.

8. Running tap water wash - 30 sec.

9. Fixer

Your common fixer, 3 minutes. Just to be sure.

10. Running tap water wash - 30 sec.

11. If you wish, immerse your slides in a selenium toner solution to give them more permanence, for 2 minutes.

12. Wash 10 minutes, treat with something like Ilford Ilfotol, hang to dry.

This should work fine, giving you the real beauty

If there's any questions regarding the process, ask me and I'll write more - that's just a preliminary but fully working protocol.

Cheers from Moscow,
Zhenya

 

[Kobin]

Thanks, Zhenya.