U of S | Mailing List Archive | alt-photo-process-l | Re: Gum Humidity Question

Re: Gum Humidity Question

Well, I just caught up reading the posts on this gum humidity issue, and this is the first time I have ever been able to follow anything at all about gum--in any way-- on this list. So, naturally, I feel I have to chime in here.

I really just wanted to add that I was fortunate enough to be in Kerik's workshop this past weekend in Philadelphia at Project Basho, and without a doubt, it was one of the best workshops I've ever encountered-- informative, detailed, very hands-on (we all made tons of prints all day Sat and all day Sunday)--and it was fun. It was really a great group, too, and I know we all learned a lot. I am one of the least technically-oriented people I know, and I was very impressed with the way Kerik managed to get all this information across in such a low-key and easy-to-understand way. He is also very patient. I know I sound like a paid announcement here, but while I'm at it, I may as well add that Project Basho is offering some terrific workshops and classes. The owner, Tsuyoshi Ito, is a very talented photographer himself, and a fine host! So, for my money, the gum over workshop was definitely worthwhile--very impressive.

Also, while the humidity was exceedingly high, I don't think the development problems were nearly as bad as Kerik has stated. No sandpaper was actually used/harmed in this process. :) I am glad that the issue occurred, though, since I'm living in NC, where the humidity is always high--so that experience was very useful. Better that it occurred in a workshop setting, where someone knows what's happening, than have it happen to me here at home, alone, and totally clueless. I'm also going to be including some of the prints I made in the workshop in this current portfolio exchange, so if anybody here is on that list to receive it, you can see the results.

I'll return to my usual lurking status now, but I'm definitely going to purchase one of those hygrometers. Thanks!


On Sep 26, 2006, at 7:32 PM, ericawd wrote:

I use a hygrometer I purchased at Home Depot for about $20.00. It works
quite well for my purposes. I can tell you that much above 55% RH, the
process does not work. I think what happens is the solution leaches into
the gelatin and causes major stain. This is from my personal experience.

As far as low RH, the RH dropped to 27% last winter here in Memphis and the
solution set up way to fast to be able to work it properly. (I had to buy a

I have a dehumidifier for the summer months and keep it in the 49-52 range.
We had our first cold front of the fall and the humidity dropped
significantly. The results were rather unexpected-more contrast that I had
been getting from the same neg. At first I chalked it up to the vagaries of
gum, but then I thought about it and started thinking about the drop of
about 7% I had experienced.

I have only been aware of the effect of RH on gum for the past year. This
will be the second winter cycle. I will see what happens. I was wondering
what others have experienced.

Thank you for your input. Good luck finding a decent hygrometer.

Candace Spearman

----- Original Message -----
From: "Katharine Thayer" <kthayer@pacifier.com>
To: <alt-photo-process-l@usask.ca>
Sent: Tuesday, September 26, 2006 5:11 PM
Subject: Re: Gum Humidity Question