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neil poulsen
27-Sep-2014, 21:06
Suppose that a 16x20 sheet of paper doesn't lay properly on a 20x24, four-bladed easel, and this results in areas that are out of focus. Short of using a vacuum easel, what are ways that one could resolve this issue?

N Dhananjay
28-Sep-2014, 05:48
Maybe you could try rubber cement or some kind of tack adhesive. Cheers, DJ

Alan Curtis
28-Sep-2014, 07:53
Double sided tape might work. Generally, it is easily removed on both surfaces.

Daniel Stone
28-Sep-2014, 16:32
Try building a steam box to slightly soften the paper before putting it into the easel. Similar to how steaming a shirt can reduce/remove wrinkles, the fibers in large paper can react the same way to make it lay flat during exposure. Keep an electric kettle or an iron w/ a steam function handy for this purpose(making steam), and a couple of large cookie sheets for handling the paper safely in/out of the box).

Just an idea of course, and normally I'd test myself before recommending, but since my darkroom is currently packed away, I wanted to share anyhow.

-Dan

[edit]
You could also check into neodymium magnets and use them to "pull" the blades down onto the base of the easel more than gravity does alone.

Greg Davis
28-Sep-2014, 17:06
Darkroom Cookbook has a recipe for making a sticky easel to solve that problem.

ic-racer
28-Sep-2014, 17:52
I had this trouble. I let the paper 'rest' a little before I made the exposure, after I closed the blades. What was happening is that the paper would move a little up or down immediately after closing the blades. By pausing after setting the blades down before I made the exposure I was able to eliminate the problem.

neil poulsen
28-Sep-2014, 21:49
Try building a steam box to slightly soften the paper before putting it into the easel. Similar to how steaming a shirt can reduce/remove wrinkles, the fibers in large paper can react the same way to make it lay flat during exposure. Keep an electric kettle or an iron w/ a steam function handy for this purpose(making steam), and a couple of large cookie sheets for handling the paper safely in/out of the box).

Just an idea of course, and normally I'd test myself before recommending, but since my darkroom is currently packed away, I wanted to share anyhow.

-Dan

[edit]
You could also check into neodymium magnets and use them to "pull" the blades down onto the base of the easel more than gravity does alone.

Sometimes they use an ultrasonic humidifier to condition paper before pt/pd printing. I'm wondering if this would work?

Jim C.
29-Sep-2014, 16:07
I guess forgoing the easel and using a piece of glass or plastic to hold the paper flat is out of the question ?

plaubel
29-Sep-2014, 23:16
If not using Baryta, I make the surface of my ground plate wet a bit, than it's adhesive .

lab black
30-Sep-2014, 02:21
Neil,

I have used small magnets on the easel blades to add weight and in some conditions, the added weight will completely flatten the paper. If this does not work, an ultrasonic humidifier can be an additional solution. Some PT/PD practitioners choose to humidify their entire darkroom. I prefer to humidify individual pieces paper for the Pt/Pd process in a large, hinged, Rubbermaid box. The box has had legs attached so that it sits just above the humidifier's outlet. I cut a 4 inch hole on the bottom of the box for a steam inlet from the humidifier as well as a similar hole in the top of the box for an outlet. In addition, I glued a piece of plexiglass that is slightly smaller that the diameter of the box to 2 in. x 2 in. legs and the entire shelf was placed inside the box. This allows the steam to rise around the paper which sits on top of the plexiglass. Time and humidity varies, although for flattening silver paper, I typically set the humidity at 68% and start at 30 seconds to slightly relax the fibers in the paper.