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View Full Version : Shen-hao 4x5 back leak....could it be normal?!



optV
25-Sep-2006, 09:09
Hello,

I'm hoping some fellow Shen-hao HZX-45IIA users can test their camera's for me to see if a phenomena I noticed is actually normal.

Checking for light leaks yesterday, I placed a very bright, very small LED light inside my Shen-hao, sealed the back up with a film holder and turned the lights off in my darkroom. After my eyes adjusted a bit (a few minutes later) I got inches away from the camera and began to scan for leaks. I found that a very small light leaks along the length of the back line where the entire back attaches/disconnects to the camera. This is the opposite side of the film holder opening.

I haven't noticed any fogging, but I usually only have the film holder in the camera for just enough time to expose and pull it out.

I did some testing with some expired type 79 film and the results are inconclusive, there are what look like light steaks in the same place on every shot, but the film expired in 05. Also, for a control, I placed my darkcloth over the entire camera, with the lens covered and the leaking area covered, and same streaks.

Can someone test their camera to see if this is normal. I would imagine the because the filmplane is sunk in, the holder would block the leaking light.

Thanks in advance, Dan.

Herbert A Terbrack
25-Sep-2006, 10:07
When you lookled for the light leak did you test with the film holder in place or without the film holder.

Chris Pandino
25-Sep-2006, 10:36
Dan,
I have owned two HZX's and never had a problem with leaks, although I'm always leery of stray light with all cameras I use and don't usually pull the darkslide until a few seconds before I release the shutter.

I have never tried the test you have mentioned, but as long as the light can't reach the film plane it should be inconsequential. If it is a significant amount of light and duration of time, the bellows might reflect some of it back and fog the film.

If it really bothers you, consider using some felt of the type used on 35mm film canisters where the back mates to the body. IIRC, the mating surfaces are finished in a stain and varnish. You could paint it a matte black and that should take care of it also.

Ken Lee
25-Sep-2006, 11:24
If this camera provides interchangeable bellows, then make sure that the bellows are attached properly at the rear end of the camera.

I don't know about the 4x5 model, but on the 8x10, it was fairly easy to think that the bellows were snugly attached, when they were, in fact, not.

Gordon Moat
25-Sep-2006, 11:51
After your post, I did a quick test of mine, and found no light leaks. Of course, I have only had it since January, so maybe it is something that is a wear related issue, or maintenance of some sort?

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

optV
25-Sep-2006, 22:02
When you lookled for the light leak did you test with the film holder in place or without the film holder.

With the film holder.

here is a photo:
http://pages.sbcglobal.net/blindoptics/firebird/shenleak.jpg

It isn't leaking all the way around, just a very super thin leak along the side opposite of the film holder insert. You have to be viewing it at just the right angle to see it. How can I fix this while keeping the back parallel? I guess this is what I get for buying a used SH.

Ralph Barker
26-Sep-2006, 08:00
Although I've not actually handled or examined a Shen Hao, Dan, the mating surfaces between the back and the camera body is usually a stepped rabbet sort of joint, with both surfaces painted flat back to absorb any stray light trying to weasle its way into the inner darkness. If those surfaces have become shiney, you may need to repaint them. If the manufacturing tolerances on your camera resulted in a larger-than-usual gap between the mating surfaces, more drastic measures might be needed, such as gluing a narrow strip of black velvet or felt to one of the interior surfaces.

The larger question is whether you're actually suffering from light leaks coming from the outside of the camera.

optV
3-Oct-2006, 00:02
I'm having my camera repair guy install some extremely thin light seal foam (like in a film canister) around the edges on the back and the body, should fix it and keep everything flat. Thanks for the suggestions.

cblurton
8-Oct-2006, 17:40
I'm having my camera repair guy install some extremely thin light seal foam (like in a film canister) around the edges on the back and the body, should fix it and keep everything flat. Thanks for the suggestions.


The back leak is not normal. Did you bring this problem to the attention of Mr. Zhang at the Shen-Hao factory in Shanghai (zhangfmli@vip.sina.com)? He is very accommodating and stands behind his products. He may have been able to help, and he would certainly want to know about the issue in case it comes up on other customer's cameras.