double image on my 4x5--help!

[chris jordan]

I've been getting a double image on my 4x5 chromes when using the front rise on my Wista SP. The second image is only a couple of millimeters away from the fir st one, and it is more pronounced in some areas of the image than others. Any s uggestions? Things I've checked so far: no problem with the bellows, and it's not the film moving inside the film holder during exposure (I tap them before in serting to make sure the film is solidly on the bottom of the holder). Possibly a lens problem? I use a Nikkor 210 W. Any help would be greatly appreciated.

[Michael Kadillak]

I have been racking my brain for a reason for the double image. The only rational explaination I can come up with that has any logic resulting in a slightly offset double image combined with a front rise is if the lens is moving ever so slightly during the exposure either around horizontal axis (around the side tension screws) or by slipping down the side rails (both possibilities possibly due to tension forces of the bellows caused by the rise and attenuated by the shutter ?). I am grabbing at straws here, but I cannot justify any actions by the shutter, phantom images or flare causing this result on your chrome. Out of curosity, I would make your rise and focus your image as you normally would and then set your exposure for a second or so (or even T for that matter) and watch a particular spot on the ground glass during the test exposure to see if you can see any image shifting or other irregularities. Anyone else want to give it a try?

Good luck.

Michael Kadillak

[Erik Gould]

I had a somewhat similar problem once where I was getting a second ghost image on the film. As it turned out, a small gap had opened in the wooden lens board, creating a pinhole lens in effect. It was difficult to find. If your image is exactly double and just as sharp it probably is not a pinhole, but maybe? Seems strange that the lens and shutter could shift in exactly the same way each time. Anything might slip once, but repeatedly? Good Luck!

[Pat Kearns]

I am guessing along the same lines as Michael. I would check (1.)to see if the shutter is mounted tight enough to the lens board, (2.)the lens board is held tight enough to the front standard, (3.) the front standard is tight. When you press the shutter release cable is could be causing one of these to slip ever so slightly.

[Garry Edwards]

I can't see how it can be a pinhole, because the magnification would almost certainly not coincide. I agree that the problem is likely to be movement caused by bellows strain. Probably the best check on this is to take some test shots indoors using the maximum possible rise and/or horizontal shift, using both long exposures and flash. If there is double exposure with long exposures and not with flash, the problem is movement. The solution will possibly be to use bag bellows, which do not place nearly as much strain on the front and rear standards.

[Bob Salomon]

If you are in the U.S. you might want our service center to look at it, with the lens. We are the Wista Distributor for the U,S,

If so send it to Marflex Service 39 US 46 Pine Brook, Nj 07058 973 808-9626

Include examples of the problem.

[John H. Henderson]

The magnification, since it is only a function of lens board to film plane distance (for normal design [not telephoto or retrofocus] lenses or pinholes), is the same.

You haven't noticed this double image except when using rise? I'd look for a pinhole that is uncovered when using rise, if this is the case.

As the other pinhole theorists said, I can't imagine that anything is mechanically shifting during the exposure. What are your exposure times?

But what's odd is that the image is only a few mm away from the main image. A pinhole would have to be rather close to the lens axis to do this. In what direction is the doubled image?

Could a shutter blade be hanging up or something? (Still would not cause a shifted image, though, I think.) Since the source of the iamge is near the lens, I'd check that the lens is firmly mounted to the board.

[John H. Henderson]

Set your camera up in the same configuration that it is when you have this problem and focus on a high contrast, sharp-edged such as black type on white paper, and look carefully under a dark cloth to see if you can see this doubling. If it is not a transient phenomenon, and you can see it on the film, you should probably see it on the ground glass.

Fire the shutter while looking through at the ground glass. Don't know if you'll see anything long enough to be useful, but it can't hurt to try and see if you see anything.

[Eric Blevins]

I really do not think anything moving during an exposure would cause a double image ,except if you were using a flash. I would think if anything moved during an exposure, everthing would be out of focus and there wouldn't be a double image, just a "smeared" one. Again, I could see this happening if you were using a flash or multiple flashes and something moved. Are you using a flash? I keep thinking of that anti-halation layer on film too,(isn't that put on film to keep these types of things from happening) but surely this couldn't be the problem.

[chris jordan]

hey all-- thanks so much for your thoughts. the pinhole concept is the only one that i hadn't thought of, though (i've been wrangling with this for a couple of years). my exposures are all long (10 minutes to 5 hours), and one time recently I shot thirteen sheets of the same image and every one had the same ghost image problem. i've eliminated any kind of movement as the source, because the ghost image is identical every time, even after the camera has been in place for a really long time and everything has had a chance to settle into place. the ghost image does not show up on the ground glass (i've tested with bright specular points of light), and i've also looked all around inside and out of the bellows with a powerful flashlight in the dar-- no problems! what a conundrum. i think the only things it could be are a problem with one of the elements of my lens being out of alignment, or a pinhole on the lens board (improbably though-- it's a wista metal board). i'll get both of those checked.

by the way, what a cool group this is! i've been lurking for some time; this is my first post. best regards to you all.

chris jordan, seattle (chrisjordanphoto.com)