Kentmere, Foma, Oriental Paper Edge Fogging

[Toyon]

I thought this information would be useful to B&W darkroom users.

I've had some problems with a yellow edge stain on some Kentmere, Foma and Oriental papers. I contacted technical staff at Kentmere, they sent me the following response... "we were forced to remove minute traces of cadmium from the emulsion formulation under environmental laws,and as a consequence the paper has become more susceptible to developer induced fog-the Yellow staining you are unfortunately experiencing.
In our catalogue (Kentmere) we advise that this product is not compatible with phenidone-based developers.We have also found that very active standard PQ developers can create the same fog.If this is the case using the developer more dilute and reduce the developer temperature and reduce the development time. We test using standard Ilford and champion PQ developers @ 1-12 at 20°C developed for 90-120 secs with no staining.

After working hard to find a developer that develops rich blacks - lPD, now I have to find a replacement. Any suggestions on paper developers that meet the above requirements? I was thinking about Ilford Bromophen.

[Doug Howk]

For Kentmere Kentona I use Photo Formulary 106 (Edwal 106) diluted 1:15 at around 70 degree temps. Kentona is very prone to developer fogging, and this routine seems to work fine.
For Kentmere Bromide I've never had any problems with fogging, and have used numerous developers including Dektol, Ansco 130 & Ilford Cooltone

[JW Dewdney]

You might also try printing and processing WITHOUT a safelight...

[Gary L. Quay]

I really like Ansco 130, which you can mix yourself from raw chemicals, of buy from Photographers' Formulary.

--Gary

[Doug Howk]

Forgot to mention in earlier post for Kentmere Kentona that, even with dilute developer, dev fogging can still occur (just reminded of that while working in darkroom this morning ;-( To avoid developer fogging (yellowing of edges, etc.) I add Benzotriazole & Potassium Bromide to the developer - 5ml KBR(10% solution) + 5ml Benzo(1% solution) per 1000ml of developer + water. Never had this problem with Forte Fortezzo, so makes me wonder if they used Cadmium.

[j.e.simmons]

I've also been forced to experiment with adding KBr and Benzo to my developers to eliminate fogging with Kentona. An advantage to this is that I have been able to adjust the image tone to my liking, too. I have varied both Michael A. Smith's amidol formula and Ansco 130.

I had been able to use both these developers unaltered in the winter, but when the temperatures in my darkroom rose in June, the fogging showed up. The fogging is definitely from the developer - not safelights.
juan

[Toyon]

Thanks all for the suggestions. J.E., I am interested to know how the addition of Benzo altered the tone of your prints. Also, I've found that Benzo slows development. Did you need to add time to the developer soak?

[j.e.simmons]

KBr warms the print, Benzo cools it. I experimented with adding each until I found a color I liked.

I do most of my developing with the modified MAS amidol formula, so what I say may or may not affect other developers. I don't find that the restrainers slow total development - I shoot for around two minutes. However, I do see that what Ansel Adams called the emergence time - the time before the initial part of the image appears - seems to be slower. Since I don't follow his practice of printing based on emergence time, I haven't made any real tests - I'm reporting my general impressions.
juan

[Ron Mowrey]

It is not normal for a paper emulsion to have a yellow stain or fog upon the removal of cadmium from the emulsion formula. Basically, you get a softer toe with a tiny change in tone of the silver metal image.

Ron Mowrey

[Toyon]

It turns out that Ilford Universal paper developer has both KBr and Benzo in the formulation. That will give me a good basis for retesting the paper. Other than the edge fogging, and a bit of emulsion loss 1mm from the edges of the paper, Kentona is really nice.

[Gene McCluney]

The above post regarding cadmium removal by Ron Mowrey should be considered the most authoritative comment on this, as Ron is a retired emulsion engineer formerly with Kodak. I would suspect that the Kentona and other papers you may be having problems with are exhibiting issues other than the removal of cadmium.