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Stefan Lungu
2-May-2011, 14:13
I am having a problem with my 6x9 Horseman roll film holder that is showing by an overexposed thin vertical line and I think it is because of the dark slide of the holder that is not exactly straight. Since I like shooting 6x9 with my crown, I was wondering if any of you could tell me a good way to straighten the dark slide.

Regards, Stefan

Steven Tribe
2-May-2011, 14:52
I don't understand how an edge problem with a bent dark slide could produce a complete line. Emulsion, perhaps or a split in the curtain which opens up when the speed - OK, you have Crown, sorry. Perhaps one the seals of the roll holder is faulty?

Stefan Lungu
2-May-2011, 15:01
Hello Steve,
It looks like this :
http://farm4.static.flickr.com/3463/3295029561_04d9d2eca8.jpg
Even if it is not strong due to post processing of the scan, depending on subject and light it can be more severe. As far as I could tell, the seals looked ok to my eye.

Regards, Stefan

Gary Beasley
2-May-2011, 15:11
That looks more like a bad seal at the hinge end of the roll film holders shell.

TheDeardorffGuy
2-May-2011, 17:09
Far more details are needed.
before the film is cut, Is it in the same spot?
Are you using the FP shutter?
Is there a screw missing on the top or bottom of the RFH?
Have you checked the felt strip on the Grafloc Back?
Have you checked the flatness of the Grafloc Back?
Have you checked the lefthand side of the rear bellows frame?

Jack Dahlgren
2-May-2011, 17:50
Note that because it is roll film, the streak may be created at a different time from when the image is exposed. For example, there might be a light leak at the light trap. This would expose a thin strip of film, then as the film is advanced it could show up in the image.

Look at the whole roll of film and see if a pattern shows up, then put the film in the camera and see if you can find where the leak may be.

Stefan Lungu
3-May-2011, 00:17
I expect the problem to happen after the exposure, at a certain moment when something is happening. It happens pretty much in the same place in the frame, and since it is vertical I expect it to happen at a moment when the film is not moved. I will try and do what Jack proposed, hope I can do this somehow that the film is almost in the same position as when it was originaly exposed.

GPS
3-May-2011, 00:57
I am having a problem with my 6x9 Horseman roll film holder that is showing by an overexposed thin vertical line and I think it is because of the dark slide of the holder that is not exactly straight. Since I like shooting 6x9 with my crown, I was wondering if any of you could tell me a good way to straighten the dark slide.

Regards, Stefan

Make yourself a second dark slide, made of plastic (you can find the convenient material in a paper shop on many presentation folders etc.). Like that you will see if the problem persist (not attributable to the dark slide) or not. Check the material with a torch first - some of it is not light tight, many types are.

Revolucion Artistico
3-May-2011, 12:52
Dark slides are quite easy to make out of thin aluminum, which you can get at Ace hardware online or a hobby shop, if you have some basic tools to cut them and file the edges etc. I just bend the end up at 90 degrees for a pull handle. Here's a link to the sheets at Ace

http://www.acehardware.com/product/index.jsp?productId=1308453&clickid=body_rv_img

That's for a pack of six but they sell them individually as well and you can choose from three or four thicknesses, I make Technika III lens boards out of them as well.

Good Luck
Ryan

Bob Salomon
3-May-2011, 13:44
Never seen an Ace Hardware in Germany.

al olson
8-May-2011, 16:37
Note that because it is roll film, the streak may be created at a different time from when the image is exposed. For example, there might be a light leak at the light trap. This would expose a thin strip of film, then as the film is advanced it could show up in the image.

Look at the whole roll of film and see if a pattern shows up, then put the film in the camera and see if you can find where the leak may be.

I had a similar problem with a Bronica back. I finally traced the problem to a slight gap where the cover closed over the roll holder. As a result, when I was in bright sunlight, it appear on the frame following the frame that was being exposed.