Re: Platinum/Palladium & Paper Speed

I made a platinum order in 1993 on "Arches Aquarelle" 300 gr "satin" just before they coat an alakaline reserve .
During order, they change their paper.
Blacks were far more clear.
I have had to make three acidic baths to 30°C to balance the PH of the paper, and I have been able to finish the order under applause.

  ----- Original Message -----
  From: Eric Neilsen
  To: alt-photo-process-l@usask.ca
  Sent: Tuesday, May 30, 2006 5:02 AM
  Subject: RE: Platinum/Palladium & Paper Speed

  If water facilitates the process and a thicker piece of paper holds more water, is it faster? Does the water slow the process, thinner is faster as the water is removed from the arena?

  In my memory bank of coating experiences, a thinner coating is faster, but also more prone to bronzing. I don't recall though, if I tested that with different mixes or if I just increased the volume and that decreased the bronzing with a particular paper.

  And I also think it important to say whether it is in factory condition and has the paper been soaked, treated, or otherwise altered with the exception of the coating solution. If "all other variables are held constant", does that just mean that if a paper was available as a 180gm paper and as a 300gm paper you consider that constant?

  If you do find something in Dick's book, please site the page(s).

  Sounds like you have some time on your hands : ) have fun

  Eric

  Eric Neilsen Photography

  4101 Commerce Street

  Suite 9

  Dallas, TX 75226

  http://e.neilsen.home.att.net

  http://ericneilsenphotography.com

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  From: Ender100@aol.com [mailto:Ender100@aol.com]
  Sent: Monday, May 29, 2006 1:34 PM
  To: alt-photo-process-l@usask.ca
  Subject: Re: Platinum/Palladium & Paper Speed

  Hi Eric,

  All good questions, but I am referring to just differences in paper speed given all other variables are held constant. I'm not asking because it is a problematic issue for me, my question is just out of curiousity. What factors affect the speed of different papers? Now that I think of it, I think DIck Arentz has some reference to this in Platinum & Palladium Printing, Second Edition, I'll read that and report back. But in the meantime, are there other processes where all variables kept constant, except paper, where different papers exhibit different speeds?

  Thanks!

  Best Wishes,
  Mark Nelson
  To NSA: If you are reading this email, could you please search your database for my other black sock?
  Precision Digital Negatives--The Book
  PDNPrint Forum at Yahoo Groups
  www.MarkINelsonPhoto.com

  In a message dated 5/29/06 1:24:13 PM, e.neilsen@worldnet.att.net writes:

  Mark, One of the primary chemicals that is part of the process is water. I'd check to see how it is being affected by the procedures being used. Was the paper humidified before exposure? What type of contact frame was used to make the exposure? Vacuum or split back? Sealed unsealed with regard to a vapor barrier between the glass/neg/paper/backing? Heat level during exposure?
   
  Which of these inhibit the movement of water, and which accelerate or facilitate it? Is it localized?
   
  And then there is the light source. or UV rays. How are they passing through the paper? During exposure as well as after when the image is formed and being revealed to the eye as a reflected image?
   
  If it were true in other processes, are they also using FO, and/or AFO?
   
  Have you put this question to Mike Ware? He at least did some scientific study of the PT/PD process which was published years back. Perhaps, he can give you some additional insights.
   
  Eric
Received on 05/29/06-11:43:08 PM Z