double image on my 4x5--help!

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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 first one, and it is more pronounced in some areas of the image than others. Any suggestions? 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 inserting 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.

-- chris jordan (cjordan@yarmuth.com), March 07, 2001

Answers

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

-- Michael Kadillak (m.kadillak@home.com), March 07, 2001.


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!

-- Erik Gould (egould@risd.edu), March 07, 2001.

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.

-- Pat Kearns (pat.kearns@coopertsmith.com), March 07, 2001.

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.

-- Garry Edwards (bestsnapper@freenetname.co.uk), March 08, 2001.

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.

-- bob salomon (bobsalomon@mindspring.com), March 08, 2001.



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 (jhende03@harris.com), March 08, 2001.


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.

-- John H. Henderson (jhende03@harris.com), March 08, 2001.


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.

-- Eric Blevins (eblevins@moh.dcr.state.nc.us), March 08, 2001.

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)

-- chris jordan (cjordan@yarmuth.com), March 08, 2001.


Check to be sure the shutter's closing all the way and not leaving a an open pinhole when it's supposedly closed.

-- John Hicks (jbh@magicnet.net), March 08, 2001.


one detail that supports the pinhole theory is that i only get the ghost image when i'm using very small apertures. if i have a pinhole problem then the ghost image probably just doesn't show up when shooting at larger apertures because it doesn't have enough time to expose the film. tonite i'm going to do some close examining with my flashlight.

another funny thing (which is why i thought others might have had this problem): i was recently looking at a coffee table book of nature shots, and i noticed that this one photographer's work all had the same problem, but the images were printed in the book anyway. the bottom half of every picture had the ghost image immediately adjacent to the correct image, and the ghost image disappeared up nearer the top half of the image-- just what i get. i wondered if it is some internal reflection inside the film at extremely low light levels but if that was the case, everyone who shoots with very long exposures would have experienced the same problem.

-- chris jordan (cjordan@yarmuth.com), March 08, 2001.


Re: Chris' last paragraph, a pinhole leak will often result in uneven illumination. Let's say, for example, that you have a small leak where your lens is mounted to the board. The back elements of the lens may block part of the illumination of the pinhole.

The long exposures can also explain why a pinhole leak may show up in the film but not on the GG. The intended exposure, being of greater light intensity than the pinhole, "saturates" the film (reciprocity failure) while the pinhole image continues to "accrue" at the original film speed.

I'd take of the GG and get a bright lamp and look for leak. Look for something extraneous with the shutter open, too.

-- John H. Henderson (jhende03@harris.com), March 08, 2001.


No sweat. Just turn the film holder over before you take that back- up shot. Cheers!

-- Bill (bmitch@home.com), March 08, 2001.

Chris: I think you can eliminate film as the problem. I suspect you have a pinhole either in the front of the bellows or the lensboard. Remove the back, put a light inside the camera and hang the focusing cloth over the back. Raise the lens standard to duplicat the rise. Turn out the room lights and check the front of the camera very carefully. I would suggest you use a 10 or 15 watt bulb in the light and don't keep it on long. You might want to sit in the dark a bit to allow your eyes to adjust to the darkness before you turn the light on. Move the front standard up and down to different positions. Check carefully that the shutter is closing all the way and not leaving a very small opening. That is not uncommon. Soemtimes the blades bounce open. Check both the lens board and mounting and the very front part of the bellows. I would also try extending the bellows all the way. Even metal lens boards can have a loose screw or a fault in the metal.

Hope this helps,

-- Doug Paramore (dougmary@alaweb.com), March 08, 2001.


Chris, I've had that happen to me before with 8x10. I think there is a chance that your film may be "slipping" or popping away from the holder during exposure, especially if you are exposing for a few seconds. Maybe give the film a chance to settle once you pull the slide out.

I've also been told that TMAX 100 has greater chance of "popping" outward if the surrounding area is humid.

Just a thought?...

-- Dave ANton (daveanton@home.com), March 08, 2001.



Sounds like a lot of potential for fine art to me. I'd leave it alone, tell everyone you're making a comment on modern society's post post modern propensity to transform life into a series of historical connundrums, or some other such meaningless art babble. You'll probably become famous, all because of this problem no one could solve.

-- Brian Ellis (bellis60@earthlink.net), March 09, 2001.

If you're checking for pin holes, I thought I'd suggest another way to do it. This works very effectively for me in diagnosing such problems and then making sure they're fixed. Go to a marine supply store and get a small survival strobe. Put it in the camera (flash, flash flash...) mount a lens, stick in a film holder, and in your darkroom with the lights out and yours eyes adjusted to the dark take a good look. Putting the camera on a tripod in the darkroom, with the horizonal set loose so you can spin it around works well. The flashing gets your attention and even extremely small light leaks show up this way. You don't have to worry about damage from heat and you don't have to run a light cord into the camera. Plus with the filmholder in place it's all sealed up like it would be in use. Put your finger over the pin hole and turn on the lights. When all your light leaks are fixed it's a handy object to put in your car for when you break down.

-- kevin crisp (krcrisp@aol.com), March 09, 2001.

You sure you haven't got a 3-D camera? with one image off-set slightly from the other all you'd need is the right glasses.

-- Sean yates (yatescats@yahoo.com), March 09, 2001.

To determine if it is a pinhole (and not the shutter sticking), set the camera up as you normally would for one of your photographs. Check that the shutter is closed. Insert a film holder and, with the shutter still closed, pull out the darkslide and leave it out for the length of time that you would for one of your normal exposures. Re- insert the darkslide and develope the film. If there is an image on the film you have a pinhole. I would also, while the camera is set up, repeat the above procedure 3 times. 1) with a darkcloth or black card covering the bellows area below the front standard. 2) with a darkcloth or black card covering the bottom half of the front standard and lensboard. 3) with a darkcloth or black card covering the top half. I would only do these last three in an effort to narrow down the location if I were unable to find the pinhole by the methods described by the other postings. Please let us know the cause was you figure it out...everyone loves a mystery...a long as we get the solution.

-- Gary Jones (jonesgp@dteenergy.com), March 12, 2001.

I had this problem once. It was because of a pinhole.

-- William Marderness (wmarderness@hotmail.com), March 13, 2001.

The only other thought is that you are geting a specular reflection from some other surface which only comes into the camera's view on when rise is used.

-- Laurence Cuffe (Laurence.Cuffe@ucd.ie), March 14, 2001.

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