[alt-photo] Re: Weston Diploma Parchment

[Clay Harmon Website]

How old is the ferric oxalate you are using in your sensitizer? My first thought is that it could be fogging from some old sensitizer. Even 2 month old sensitizer can give some slight fogging.  If it has been mixed a while, try mixing up a small amount of sensitizer and see if you get the same problem.

I was printing yesterday, and had some ferric oxalate that I had mixed up in late December. I was getting a faint amount of fogging with it.

Clay
On Mar 8, 2010, at 4:25 AM, Jon Reid wrote:

> Hi all,
> 
> I have been battling a problem for about 6 months now. At first I thought it was a clearing problem then after trying various things realised that it wasn't clearing but rather some density that was appearing in the coated area of the paper that is masked during exposure. The paper that I have been trying to print on is Weston Diploma Parchment. I bought this paper in early 2008 from Bostick & Sullivan and believe it is stock that was made by Cranes, not the re-invented Diploma Parchment Plat Pal being marketed by John Zowkowski of Butler Dearden.
> 
> I am wishing to print my 5x7 rollo-pyro negs on these 11x14 sheets for my debut solo exhibition. I do not want to mat the prints so I am trying for very clear coated-but-masked areas. The other night, believing I was dealing with a fogging issue I set up darkroom safelights and coated under those lights. I then used a hair dryer  and rested the paper in the room for 10-15min before exposure (11min in my UV box), and developed in KOx (cold bath version-fresh) at 21C. The room lights were not switched on until after I had finished dev and rinsed the paper. The density in the unexposed area was less than it had been but was still there (see link to
> parchment1.jpg below
> http://sharperstill.com/jonreid/pics/parchment1.jpg
> parchment2,jpg shows the same problem, same print recipe and exposure going back to last October. Note the difference in contrast.
> 
> I then tried a piece of Cranes natural white wove (8.5x11sheet given by a friend). A very slight trace of density remained while it was still in the first clearing bath but has all but disappeared since. See
> http://sharperstill.com/jonreid/pics/craneswove.jpg
> 
> My gut feeling was 'Right, it has to be the paper!' I have read Mike Wares test of this paper where he speaks of a chemical fog inherent under a pure palladium print-out method. The only nagging squirrel in my belief that it is a problem in the paper is that some time ago I tested Arches Platine  and got the same result. Up until this project Platine was the only paper I have printed Pt/Pd on and apart from being stubborn to clear have never had any problems of this nature. That was what led me to believe that it was my room lights that were the problem. See platine:
> http://sharperstill.com/jonreid/pics/platine.jpg
> 
> I really want to present these pictures on the wall in a certain way. and I don't think that Cranes natural white wove is available in 11x14, and probably especially not here in Aust.
> 
> I don't have any specific questions from the list but invite thought, experiences and queries from any list member who might be able and want to contribute. This has been a tremendous source of frustration for me. Thank god I didn't have a deadline.
> 
> Jon
> (Sydney, Australia)
> PS: Is this the paper formerly known as Platinotype?
> http://www.crane.com/prdSell.aspx?NavName=NavShop&DeptName=BusinessStationeryandAccessories&SubDeptName=CranesCoverStock&Name=21473_Cranes90lb.CoverStock23x29Sheets
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