From: Alan Bucknam (alan@notchcode.com)
Date: 01/13/03-09:24:10 AM Z
Eric,
thanks for the info.
I'm using Ammonium Citrate, sometimes substituting Cold Bath Developer,
although in the case of this print, it's 20 degree C Ammonium Citrate.
Once I'm done with this rather rushed project I'm currently wrapping
up, I'm inclined to try Ammonium-based platinum solutions. I've already
intensified for a total of about 36 hours, with regular agitation each
hour or so, in selinium diluted 1:4. It's helped, but not enough. I
need about one more stop. I'm already using all solution B, no solution
A, and pure platinum in my C mixture. I even tried double-coating, but
that really didn't do much, other than slough off a lot of extra metal
precipitates into my developer.
On Sunday, January 12, 2003, at 08:53 PM, Eric Neilsen wrote:
> Alan, You can indeed increase contrast with a dilute developer. And
> yes, you will see more grain. Most contrast increasing methods increase
> grain to some degree if done during printing. Are you using Pot Ox as
> your developer? This can be diluted about a 1/3 before grain becomes
> to
> much of an issue. The paper and other factors will of course determine
> just how grainy. I have not seen unpredictable results due to dilution
> of a developer. You will of course need to run some exposure test, but
> you will get consistent results. You will need to add exposure time to
> make up for a weaker developer. 15 to 25% would not be uncommon.
>
> Try a different developer? More platinum? A different platinum? The
> ammonium based platinum will increase your contrast over Potassium
> based
> platinum.
>
> And the big question is, "Just how much contrast are you looking to
> add?"
> Carl's suggestion of selenium should not be over looked as a good way
> to
> bring up a close but not quite there negative. This however, requires
> that you have a good clean negative; not all scratched up as the toner
> will work unevenly on a scratched emulsion.
>
>
>
> Eric Neilsen Photography
> 4101 Commerce Street
> Suite 9
> Dallas, TX 75226
> http://e.neilsen.home.att.net
> http://ericneilsenphotgraphy.com
>
> -----Original Message-----
> From: Alan Bucknam [mailto:alan@notchcode.com]
> Sent: Sunday, January 12, 2003 2:53 PM
> To: alt-photo-process-l@sask.usask.ca
> Subject: getting more contrast out of pt/pd developer
>
> I've been doing the usual trick of increasing contrast in my pt/pd
> prints by reducing the developer temperature, but has anyone
> experimented with getting more contrast via diluting the developer
> itself? I thought I saw something mentioned to that effect in the
> alt-photo archives, but wanted to hear from someone about it
> specifically.
>
> Alan
>
>
>
>
This archive was generated by hypermail 2.1.5 : 02/21/03-10:44:16 AM Z CST