Efke R 100 Reversal processing

[nexus757]

I tried to reverse process some Efke R100 tonight to make direct positive slides. Followed the Ilford published formula more or less with hypo added to the first developer, and permanganate bleach.
The film looked normal after bleaching and clearing and I re-exposed under light. It was after the second development that the emulsion became so soft it literally fell off the base during drying. Totally bizarre--I've never seen anything like it and I've done many a B/W reversal film over the years.
I see B&H is now promoting this film as a "reversal film" for slides. Anybody else tried to reverse process it? All I got was a big mess--and again, I'm really not a rookie to the reverse process. I've done hundreds of 16mm films and slides this way over the years on both Kodak and Ilford films--but I have never seen emulsion get so soft it literally falls off! Any suggestions?
Should I try dichromate rather than permanganate bleach?

 

[willrea]

I use dichromate and I've heard using it does help harden the emulsion.

 

[vencahaus]

All efke/adox chs films are very fragile and when you don't treat them very carefully the emulsion goes down even in ordinary negative process.

I reversally processed this film, using dichromate bleach with good results. It also depends on the second developer. Don't use rodinal, for example.

I prefer CHS 25/R25 due to better (higher) contrast.

 

[Ian Grant]

When I first used EFKE films in the 1970's I used to add hardener to my developer just prior to use but in more recent years EFKE began hardening the films slightly better.

Permanganate bleach will soften these emulsions to much so dichromate must be used this has a hardening effect anyway so helps enormously.

The advice to stay away from Rodinal is a good one as it has a very high pH but what's worse is it contains free Potassium Hydroxide, this softens emulsions very quickly.

Ian

 

[brucemuir]

Happened to me with TMX & permanganate bleach step.

http://www.flickr.com/photos/brucemuir/sets/72157622875693837/

I think in my case it was from solution temperature fluctuation and cleared up after I tightened my process control.

 

[nexus757]

Interesting photos Bruce. Here is a link to my results on Efke R100:
https://www.facebook.com/album.php?aid=2099407&id=1027053568&l=46a64e0184

As you can see the emulsion literally began to dissolve and separate from the base, creating a runny, gooey muck.
I processed some Ilford FP4 with the same chemistry today and it did fine. I can only assume the Efke film does not respond well to the Permanganate Bleach.
Ed

 

[nexus757]

A cropped and enlarged section:
http://www.flickr.com/photos/9645031@N07/5480343008/
Kind of a cool effect actually--but I'd hate for a wedding shoot to turn out this way .

 

[brucemuir]

Hey Ed,
Yea, your photos are visible as thumbs but the link has expired when I click for a better view.

Your issue looks different than what I experienced but who knows?
Yours look way cooler as well for what that's worth

 

[nexus757]

Just as a followup: I tried cutting the amount of permanganate in half and the EFke emulsion reversed fine without damage. The strength of the acid was not changed.