Brown stains on VC FB paper

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Hi, I'm pretty new at darkroom work. Recently I've just purchase a pack of Kentmere Fineprint VC FB paper, I did two set of the neg with different contrast settings. One with and one without. Can anyone tell me why the one with a 0 filter cames out much lighter than the one without a filter? Also why does brown stains begin to appear on the print after a day or so? Is this becuase of insufficient fixing or is it becuase of insufficient washing? Thank for taking time to answer my questions. :)

-- Kenneth Seah (seahnet@singnet.com.sg), January 02, 1998

Answers

Being a negative material, the paper will go darker with more exposure to light, or lighter with less exposure. If you put a filter in the light path, the paper will receive less light than without the filter, hence it will be lighter.

The answer is to do test strips with the filter you intend to use. If you want to change the filter, re-do the test strip. As you probably know, the purpose of the filter is to change the contrast of the print, so although there are conversion factors for combinations of paper and filter sets, they are only approximate.

I'm not sure if the brown stains come from insufficient fixing or washing, but you are right, it's one of those. The paper should come with recommendations for both fixing and washing. Be aware that (a) these will be MINIMUM times, and (b) if you give it more fixing, it will need more washing.

For fibre-based paper, I would never wash for less than one hour in flowing water. But then, I normally (always) use RC paper. If you are just starting out, and it sounds as if you are, you may prefer to gain experience with RC paper.

-- Alan Gibson (gibson.al@mail.dec.com), January 02, 1998.


brown stains

I would agree that the problems solutions are as Alan stated. But I would add that washing FB prints for one hour is really not necessary if you use a Hypo Clearing Agent. A short pre-wash, 5 min in a HCA and a 10 min final wash in a good washer in enough. There is also a problem with extended washing times (beyond the obvious Eco ones) that you can begin to remove the print brighteners, resulting in duller highlights.

-- jim megargee (mvjim@interport.net), January 02, 1998.

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