black specks on platinum prints

[RobertP]

Ive developed black specs on my platinum/palladium prints. I've filtered my palladium, ferric oxalate, and potassium oxalate through Whatman filter paper and I'm still getting them. The only thing that is different than before getting them was I opened a new pack of platinotype paper. I've closely looked at the paper and I can't see any type of blemishes that would cause a problem. It looks exactly as the last pack of paper looked, by eye. Does anyone have any idea what may be causing this?

 

[scootermm]

robert, Ive had similar issues when making prints on platinotype (AKA 90# cover) and I believe Ray Bidegain mentioned in the past he had similar issues. I found when I opened another batch of paper the problem was no longer. So more than likely some sort of "bad" paper batch. Ive also experienced it from minor metal shavings that get left on the paper when I cut it with a paper cutter or exacto and dont wipe it off adequately.

hope that helps. Id give another batch of paper a try and see if that fixes it.

 

[JBrunner]

Dick Arentz describes this problem in his book "Platinum and Palladium Printing"

He calls it "The Black Plague"

He infers that it may be caused by defects in the paper stock, foreign matter in the coating brush, or particles in the coating material, such as metal salt precipitates or other contaminants. But he also infers that it is a fairly mysterious problem, and that while these are the most likely causes, the spots can still appear at random.

I recommend this book to anybody who is interested in platinum printing.

 

[Jorge]

Sometimes you need to heat up the pt or pd solutions, sometimes they come from the cutting blade if you used a paper cutter to make a smaller sheet. Sometimes the pt/pd gremlins are not happy with you...

 

[Kerik]

In my experience, black spots are most often caused by impurities in the paper. And yeah, they suck... If you hold your paper up to a bright light before you coat it, sometimes you will see little bits embedded in the fibers. Unless they are on the very surface of the paper, you're not likely to see them just by examining the paper surface.

 

[RobertP]

Thanks everyone, This was driving me nuts. I was about to dump a couple of hundred ml of solution down the drain. This is the first time this has happened to me with platinotype. I'm now running a print on opaline to see if that solves it, which after reading your replies I'm sure it will. Will the vendor take back this batch of paper or am I stuck with it? I'm sure than can't see it either by visual inspection.

 

[Kerik]

Who is the vendor? B&S might - others not likely.

Which opaline are you using and where did you get it?

 

[RobertP]

Jorge, That was my first thought. It was the metal salts. That's when I went back and reheated the palladium, ferris oxalate and the platinum. I even filtered the palladium and ferric oxalate as I said with whatman filter paper, to no avail. I'm printing for my first show which needs to be framed in the next week so I was In a state of panic and anger because for the life of me I couldn't figure out what was wrong. Well now I need to run to walmart and pick up a hair dryer the old one was splattered against the darkroom wall. Thanks again guys, Robert

 

[RobertP]

The opaline print is out of the plate burner and I'm pleased to report not a single black speck. This almost turns me off to platinotype and I really like the tone of the platinotype paper. Thanks, Robert

 

[John Jarosz]

I seem to remember that black specks were a problem with Palladio, I THINK the consensus was that it was a paper problem.

I also believe there were two problems, one where the specs were apparent after paper manufacture and the other was that some specks didn't show up until after development.

In the former case, they used to sell product with the visible specks at a big discount, that was the kind I used to buy. I never had the latter happen to me.

That's what I recall, anyway, it's been a while -- I'm sure some brain cells have disappeared.

John

 

[RobertP]

Kerik, I bought it from a guy who was sitting on it for the last 15 yr. I bought every sheet he had. Great stuff just not enough of it. The platinotype was bought from B&S. I'll give Kevin or Melody a call Tuesday and see if I can return the platinotype

 

[sanking]

In my experience, black spots are most often caused by impurities in the paper. And yeah, they suck... If you hold your paper up to a bright light before you coat it, sometimes you will see little bits embedded in the fibers. Unless they are on the very surface of the paper, you're not likely to see them just by examining the paper surface.

This is also my experience. 100% of the problems I have had with black spots have been caused by a paper problem. I have assumed that for some reasons the manufacturing process, for whatever reasons, leaves very small particles, that for one reason or anothe, react photochemically with the process.

Sandy

 

[Jorge]

Kerik, I bought it from a guy who was sitting on it for the last 15 yr. I bought every sheet he had. Great stuff just not enough of it. The platinotype was bought from B&S. I'll give Kevin or Melody a call Tuesday and see if I can return the platinotype

Of course you are free to try and return it, but if you like the paper you might try giving it a pre soak with oxalic acid. The pre soak is most likely to remove any impurities.