View Full Version : Grain on 4x5 - could the cause be exhausted bleach?

Bill Glickman
2-Apr-2001, 21:59
I have a lot of 4x5 color chromes that show a tremendous amount of grain in the skies, specially noticeable in transition areas between different colors in suns et scenes. The look, even under a 4x loupe seems to be "peppered", as if someo ne took a pen and dotted a different color over the background. Since a lot of this film was Provia and Velvia, I sent it to Fuji engineers for review, they ha d no explanation. (these scenes are all properly exposed)

An experienced darkroom guy told me that this occurs when the bleaching pro cess is done using exhausted bleach. Here was his comments....

It's the bleach. What you see is SILVER that is not dissolved by the fix, becaus e the bleach is not oxidized enough. We had the same problem in our lab years a go with Fuji's Velvia, which is hardly the worst to fix and wash out. Making a new run from Prebleach on will remove the silver but can alter the color.

My questions to any experienced E-6 guys out there....

1. Would you agree this problem is most likely from exhausted bleach. I can e mail a small sample of a sunset to demonstrate what the problem looks like if an yone is interested.

2. If so, would running this through a second bleach fix the problem? What are the risks?

3. If you feel its not an exhausted bleach issue, what else can cause this?

Thank you all in advance.

Pete Andrews
3-Apr-2001, 05:39
The exhausted bleach explanantion sounds feasible, and a second go through the bleach and fix shouldn't harm the film. The wash and stabiliser will have to be repeated as well, of course.I've only seen this effect in its extreme, when the bleach bath got contaminated and was almost useless. The film had an obvious grey mask to it as well as a grainy appearance in that instance.Does your film show any veiling?

If it's not the bleach, then I suppose that incorrect storage of the film could have caused the problem (any strange colour shift might be a clue here), or it might also be reticulation.

Paul Schilliger
3-Apr-2001, 07:42
Bill, I have the same problem on some of my Velvias. They seem to habe been proc essed by the same lab on a particular year. When I got them back from the lab, I did not notice something w as wrong. But years after when I decided to scan them, I found that the skies were full of black dirt and were al most impossible to correct (it is not limited to the skies but that's where it is the most annoying). I would be inter ested in hearing if there is a way to clean them too!

Bill Glickman
3-Apr-2001, 15:51
Here is a reccomendation from a e6 processor...any comments?

I suggest that if possible you have someone give an extended wash, say 10 minutes to remove any chemicals left in the film and to make the emulsion as receptive as possible, then give a bleach of 6 mins, a fix of 3 mins, a wash of 3 mins and finally a stab of .5 min. If that fails to work then I think you have problems unfortunately Thank you..