Re: Determining SPT with gum Was: Gums a la Demachy and Puyo

Oops, I made a wrong assumption that it was David Hatton that Loris
was responding to, and didn't look closely at the heading of the
quoted message. Now I see it was David Harris. So maybe my photoflood
hypothesis is still on the table after all.
kt

On Jul 12, 2006, at 3:43 PM, Katharine Thayer wrote:

>>
>> -----Original Message-----
>> From: David & Jan Harris [mailto:david.j.harris2@ntlworld.com]
>> Sent: 12 Temmuz 2006 Çarşamba 13:41
>> To: alt-photo-process-l@usask.ca
>> Subject: Re: Determining SPT with gum Was: Gums a la Demachy and Puyo
>>
>> Loris
>>
>> That is interesting. I agree that with the visual approach it is
>> easy to
>> choose too great a SPT.
>>
>> With gum, I get dichromate stain at exposures lower than the Dmax
>> exposure
>> so I chose my SPT based on a level of dichromate stain that is easily
>> cleared. This way I can stop my colours from getting muddy. I
>> usually do gum
>> over cyanotype so I'm not too concerned about high density.
>>
>
> Oh shoot, another hypothesis down the tube. I had always wondered
> if the reason I never get dichromate stain is because of the
> photoflood light, but if you get dichromate stain with the
> photoflood, there goes that idea. Oh well!
> Katharine
Received on 07/12/06-06:51:46 PM Z