platinum/palladium print problems

[robert]

I've developed black specks on my pt/pd prints. I've strained my ferric oxalate, palladium and potassium oxalate through Whatman filter paper and I'm still getting them. Does anyone have any idea what might be causing this? thank you, Robert

[bruce terry]

Robert - Are you cutting your print paper with a slicing cutter prior to emulsifying? According to Richard Sullivan in The New P/P Print, metal cutter faces can throw off invisible bits of lower metals that can plate-out into black spots during subsequent development. He also mentions paper can be contaminated by poorly-maintained factory machinery. Just possibilities you might already have considered.

[Pete Caluori]

If the black specks don't correspond to pinholes, or flakes in the emulsion of your negative, then I would suspect the paper or water. Try a different paper, or distiller water. Any low grade metalic compounds in, or deposited on the paper will attract the Pt/Pd metal and cause the black/brown sposts. The first thing I would do is try a different paper. Good luck!

Regards, Pete

[robert]

The problem is as Dick Arentz descibes it in his book, "The Black Plague". This is a problem with platinotype paper. But in 4 yr. printing with this paper this is the first time it has happened to me. One theory is that metal particles become imbedded in the paper during the manufacturing process. Most of these specks are not visible by eye with even holding the paper up in direct sunlight. It was driving me nuts. I just went to another paper to finish printing for my upcoming show.

[sanking]

The problem is as Dick Arentz descibes it in his book, "The Black Plague". This is a problem with platinotype paper. But in 4 yr. printing with this paper this is the first time it has happened to me. One theory is that metal particles become imbedded in the paper during the manufacturing process. Most of these specks are not visible by eye with even holding the paper up in direct sunlight. It was driving me nuts. I just went to another paper to finish printing for my upcoming show.

Robert,

There is a very high probability that this is a paper problem, and there is likely nothing you can do about it with the present batch. Try another paper, or the same paper from a different batch, and the problem will probably go away.

Most Pt./Pd. printers have run across this problem at one time or another and it usually goes away when we change papers.

Sandy