Shen Hao 6x12 Light Leaks

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Jun 9, 2015
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I recently purchased an older Shen Hao 6x12 Roll Film Back off that G.A.S enabling auction site. I finally got a chance to use it but I'm getting some strange light leaks. Maybe someone here has seen this before. There are two different leaks. One is on the the edge of the frame and is pretty easy to diagnose and fix or hopefully fix. The others have me baffled. I thought maybe it is from the red window on the back? Anyway hope someone here can help.

Lane
 

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Some claim thar red window is bad and other half claim it is not. May be this is because of the color , filter characteristics of window red.
Shen Hao is chinese , isnt it ? May be they do not use german quality. You will try and learn.

I did not see any light leak like that bad in 10 years in APUG , May be Black tape is your friend. Wait others answwers.

Good luck,

Umut
 
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Thanks for the reply Umut. I've noticed a bit of play between the back and the camera. Maybe when I'm advancing the film the play is letting in a little light. I have ordered some 1mm thick light seal foam that may work. I will apply the foam to the roll back where it meets the camera. I'm also going to learn how many rotations of the spool knob advances the film properly so I can leave the window closed. If this doesn't work I will have to use the all purpose gaffer's tape while I look for a deal on a Horseman 612 back.

Lane
 

ic-racer

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Pictures of the unit in question? Which camera?
 

BradS

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Those photos all show screws going into the flat surface that mates with the camera...why are they there? What are the screws supposed to be holding? The screws seem to me to be the obvious problem.
 
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Those screws are supposed to be like that. New roll backs of this design are the same way. The screws register the back into the proper location on the graflok back of the camera.


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Dan Fromm

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Those screws are supposed to be like that. New roll backs of this design are the same way. The screws register the back into the proper location on the graflok back of the camera.

Stuff and nonsense. I have a small mountain of roll holders that attach to 2x3 and 4x5 Graflok backs, Linhof Super Rollex and Sinar Panorama (6x12) among them. None protruding screws facing the camera lie yours. They're clearly not original, may have been added to locate the rollholder on the gate of a homebrew camera that has a home made spring back. The ridge at the right ends mate with a slot in a real Graflok/international back to locate the roll holder.

Your back is missing a pin that attaches to the sliding mask used to cover the little red windows.

You're not the first person to have had light leak problems with Shen Hao 6x12 roll holders. Here's a report with an account of how the unhappy user diagnosed the problem: http://www.largeformatphotography.info/sh612.html

Re that report, there are two interpretations of 6x12. 56 mm x 112 mm and 56 mm x 120 mm. AFAIK the only 56x120 roll holder is the Linhof Techno Rollex.
 

BradS

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Those screws are supposed to be like that. New roll backs of this design are the same way. The screws register the back into the proper location on the graflok back of the camera.

OK...looked at a few eBay auctions for this thing. (See ebay item #170958503930 for example)..looks like those screws are intended to hold some kind of format mask. With no mask, they are likely preventing the back from properly seating against the back of the camera. I'm guessing that they stick out too far...and are keeping the roll film holder from seating all the way.

The back is supposed to be completely flat except for that ridge that runs along the edge where the dark slide goes. That ridge sits in a slot on the back.
I'd recommend removing the screws, and trying again.
 
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OP
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Brad, I forgot completely about those masks. I only got the thing to shot 612. That little pin isn't really a big deal. The cover slides easily enough. I didn't pay very much for this contraption so if it doesn't work I'm not out very much money. This one is 56x11.3. Close enough for me.

I took the screws out just to see if it mated better. Nope it's actually looser. Just for giggles I put one of the masks on and bingo. The fit is much better. The 4 little locks are now snug when you rotate them onto the back. Don't know if its light tight but the fit is better. Only problem is I have no desire to take 645 or 6X6 images with this camera. I will try the foam and if that doesn't work I'm glad it was cheap!

Lane
 

BradS

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Thanks for your post. Please follow up when you have more info. I'm curious to see how this thing works. I've often thought I wanted one.
 
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