wet behind fresnal- how to dry?

[AX McEwan]

I was out photographing and it started raining. Not a heavy rain, but enough to make me pack up after about 10 minutes. I had kept my dark cloth over the bellows but the back of the camera got a little wet. I did not think it was much but after getting back I found that there was moisture between the groundglass and fresnel.

I sat it in front of a vent blowing warm air for an hour. I tried a hair dryer too for a few minutes. Neither has gotten rid of the moisture. It is in a circle around the inside. and in a couple of spots is distracting.

Looking for suggestions on ways to dry it out. Maybe some dissecent packs?

Never have tampered with a gg/fresnel before so not sure if I want to try taking it apart to wipe it.

Here is a pic of it. It is an Arca Swiss.

[Ron Marshall]

Put it in an airtight bag with silica gel dessicator for a couple of days.

[Donald Qualls]

If you find the dessicant doesn't do the job, or if you have mineral rings left on the Fresnel or ground glass after the water does finally evaporate, you'll have to remove the Fresnel and ground glass, invidually clean and dry them (dish soap and warm water, with final rinse using distilled water, then air dry standing on edge), clean and dry the frame while you have it open, and then reinstall the Fresnel and ground glass. *VERY IMPORTANT* to get the two pieces in the correct order and facing again when reassembling, so make note how they were when you take them out. Also note the location of any shims; they must go on the correct side of the correct piece to maintain correct focus registration.

Every commercial ground glass back has some kind of provision for removing these parts, in order to replace broken ground glass, though the methods of getting the glass out varies from one manufacturer to the next.

[Alan Davenport]

It will take days or weeks for the water to evaporate out from between the screen and fresnel, if it ever does. There's really no reason to be squeamish about dissassembling the screen. Just be aware that the clips that hold the fresnel and screen in place, do so by slight spring tension, so you need to keep things from going sproing when you remove the little screws.

When taking the screen apart, be sure you note whether or not there are any shims on the lens side of the groundglass. If there is, you need to ensure that it goes back in when you reassemble it. Otherwise, just slap the pieces back together in the same relative positions. The position of the GG is fixed by the surface of the frame that it rests on (plus shims if any) and there just isn't much to go wrong when you put it together. LF cameras are pretty lo-tech...

[Eric James]

:) I ran into this problem in the field last week - fortunately on my last day of shooting before returning home. One of the first things I did upon my return was to put the ground glass assembly in a Pelican Case along with a silica gel cartridge, and crossed my fingers. In the morning the moisture was gone! Good tip Ron.