RE: Platinum/Palladium & Paper Speed

Marc, There is no doubt that the buffers and sizing are part of the speed
equation. To keep the variables down to a manageable level, the same paper
at different weights may be one way to test thickness as a factor. However
as you change thickness there might be more available buffering agent to the
coating, not because there is a different density but rather just because
there is more to interact with the coating.

What did you resize your paper with after the acid treatment?

Eric Neilsen Photography

4101 Commerce Street

Suite 9

Dallas, TX 75226

http://e.neilsen.home.att.net

http://ericneilsenphotography.com

  _____

From: marc bruhat [mailto:m.bruhat@free.fr]
Sent: Tuesday, May 30, 2006 12:43 AM
To: alt-photo-process-l@usask.ca
Subject: 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 <mailto:e.neilsen@worldnet.att.net> 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

  _____

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 <http://www.precisiondigitalnegatives.com/>
Negatives--The Book
PDNPrint Forum at Yahoo Groups <http://groups.yahoo.com/group/PDNPrint/>
www.MarkINelsonPhoto.com <http://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 05/30/06-08:07:18 AM Z