Light Leak?

[sdzsdz]

Hey everybody!

Unfortunately I need your help again! After my last shoot out in the nature I discovered a problem that I never had before as the pictures came back from developing. As you see in the picture below, I have light somwhere in my pictures where it should not be. It happened on 3 different films (Velvia,Provia, Ektar) with 6 different filmholders and different resin filters (Lee, sometimes 1, sometimes 2). I never had these problems before. Do you know what this is? I had also to discover, that the sharpness decreases towards the left side continously. The camera is a Tachihara 4x5, filmholders from Fidelity and Arca-Swiss, Super Angulon 75 4,5 on a recessed lens board.


Test 1 von sdzsdz auf Flickr

Then I made a test today. I placed the camera with a sheet of Tmax 400 in a normal Filmholder without the darkslide into the daylight in my garden for about 20-30 minutes. This is what came out after developing:


Test 2 von sdzsdz auf Flickr

Is that normal??? Do you think I reproduced the problem of the real shoot (I don´t think so)? I made also a normal picture on Tmax 400 with the same holder (other side) that showed only a small strip of leaking on the left side where the darkslide goes in and out.

Do you have any suggestions?

Best regards, Sebastian

[lenser]

Since you have both a light leak, and fall off of sharpness, it would suggest a seating problem for the film holder, usually due to not inserting the holder properly. Take a hard look at you technique and be certain that the holder is fully inserted and seems totally locked down before removing the dark slide, then draw the slide straight out to avoid torquing the holder position. You also might double check the strength of the springs on the back. If one have somehow "relaxed" it's full tension, that could be allowing the holder to not be properly seated.....unlikely, but not out of the question.

[cowanw]

Recently, I had the same issues. Turns out I had pinholes, a poorly seating back assembly and a lens board mount that used roundhead screws on the lens side of the flange and prevented the lens from screwing flat and fully. At night take a flashlight and put it in the extended bellows and then closed bellows from the front with no lens (with a film holder in) then from the back with no GG (but your lens in).
Look from the outside for the leaks.