light leak on wisner 45 technical?

[MacGregor Anderson]

I've been using a toyo 45cf for about a year and decided recently to upgrade. I bought a new Wisner technical mohagany. I liked the handmade wood design and the improved movements.

I just developed my first four sheets from this camera and the negatives show some sort of light leak. Hard to describe, but I'll try.

The shot was a vertical. The sun was partially blocked by trees and fairly low on the horizon, so it wasn't glaring straight down into film holder.

The negative shows a U shaped darker area with a distinct line at the top. It's a couple stops darker than the surrounding areas but not extremely dense. The upper right corner of the U is near the top of the frame and about center. It begins about 1/8 of an inch below the top of the frame. It covers about an inch to the left and an inch and a half down. The borders of the negative are perfectly clear.

So, the leak came from the bottom of the camera in the back, or somewhere in front of that?

Sorry, this may be impossible to figure out from the description.

Anyhow, the wood has me worried. The lens boards seem pretty tight, and the bellows to front standard seems pretty well connected. But nothing like you'd see in a metal camera. There are variations in thickness, and it's all wood on wood, no gasket material for a perfect seal. Lensboards were very snug at first but by the second or third time inserting them they had loosened noticeably. Is this normal for wood cameras?

I was also concerned because there are two pins designed to hold the front rails at full extension. One of these was higher than the other and caused the standard to catch when retracted. It's a little tick now that interupts the sliding of the standard but doesn't prevent it. Seems like something that would be caught in a very simple going over before shipping.

What next? Send back to B+H? Give up on wood? Or was it something I did?

I can try some more test shots tomorrow but I'm pretty discouraged right now. The cheapo Toyo worked right out of the box.

Mac

[MacGregor Anderson]

I uploaded a small scan of this to another site. I can provide a link but I haven't seen anybody here link to photos in the past and don't know if that is violating board rules in any way.

[Rick Heitman]

just my 2 cents. Are you sure that you werent using too wide of lens and maybe a little too much rise? Only questioning because I did it. Rick

[Gem Singer]

Hi Mac,

I took a look at the shot on the photo.net LF forum. From what I can perceive, it looks like the interchangeable bellows on the camera is not seated properly. Check to make sure that the bellows frames are properly attached to the front and rear standards.

Wood expands and contracts relative to the humidity. A slight amount of play between the lensboards and the recess in the front standard is normal.

You can call, or e-mail Ron Wisner directly (www.wisner.com). Explain your problem to him. He is best qualified to offer a solution to the problem.

[MacGregor Anderson]

I'm going to post the link to the scan of the neg just so anybody who is interested can see what I'm talking about better.

Hope that's ok. It's just a photo.net portfolio, and you'll see I'm an amateur and that there is zero commercial stuff going on.

Eugene, I'll do a bit of testing tomorrow and contact Ron per your advice. Thanks for that contact info.


http://www.photo.net/photodb/photo?photo_id=3071838

Thanks again to everyone here. Hope I can return the favor one day.

[MacGregor Anderson]

Rick, sorry forgot to answer you. It was a 150mm lens on a 4x5. I did use some movements, but they didn't seem all that extreme to me. And I shot one of these at F64. The rest at 45. But who knows, maybe this camera has more movements than I'm used to, and since the ground glass corners aren't cut, I had to look for vignetting through the lens. That was a first for me.

The thing is, I figure vignetting would darken, not lighten the image.

There was a fair temperature drop from the truck to the outside, and I'm wondering if fogging on the lens could have anything to do with it. I just figure anything like that would darken the final image, not lighten it?

[Gary J. McCutcheon]

MacGregor,
I have a Tech Field about four years now. Never this problem. Did all of the photos made have this same problem? We need to eliminate a film holder problem. I had a fogging problem on a roll film holder recently and it was the dark slide not seating completely. If you determine it is not the film holder, it could be that the film holder is not seating properly into the back of the camera. If there is a slight uneveness to the edge on the bottom of the camera where the film holder rests, light could leak in there. Make sure there are no little burrs of wood sticking up that don't allow the holder to seat properly.
You may want to do a test in the darkroom. Use a bright flashlight or light that won't get hot enough to damage the bellows and with the lights out and a film holder in place, light the inside of the camera from the lens side and examine the camera carefully in the back area and see if any light leaks out, either around the bellows or filmholder area. If you see light you've found your leak. The film holder must be in place for this to work. Next, go the other direction with the back off and the the lens on with cap on. Check the top, bottom, side, every inch. It could be where the bellows attaches or where it is glued. This should help eliminate some things and maybe find the problem. As far as things like screws loosening up and the slide levers needing tightened frequently, that's part of the game. I've had ZoneVI, still have a Wista, had an Ebony, still have the old 8x10 Deardorff and they all need attention with the screwdrive now and then. Keep one in your camera bag. I've had Sinar and still have a Toyo G and they needed tuning after enough use. Wood needs a little more loving and it is more loveable. I love my Wisner camera. Just personal taste, but it seems to do everything well.
Ron Wisner will love to help you solve the problem if you can't figure it out, hopefully it's an easy fix and won't require return to the factory. The Wisner factory is digging out of a big snow storm, but Ron is answering the phone. He's always been willing to help solve any problems. B&H is a good company and should exchange the camera with you for a different one if you can't find a solution. There is a solution, just depends on how frustrated you want to get and how much you want to learn along the way.
Good luck, hope this helps.

Photo on

Gary

[John Berry ( Roadkill )]

I agree with gary about film holder or not seated as the problem. I looked at the example. I have a wizner and I have no complaints at all with it. Do you hold the holder by the edge. I had a leak like that once caused by 1. the slide was out a little. 2. I picked up 4 holders at once squeezing on the dark slide. Looking at the example, if you had a light leak it would be on the bottom back half of the bellows. Looks to local to be coming from up front. I just took my back off and put a holder in it and I don't see an angle available to cause the problem and yet leave a clear section at the edge. John Berry

[William Blunt]

I have a Wisner 4x5 that will leak light if not careful when seating film holder. When holder is put in camera it can go past the slot where the ridge on the holder rests. I just have to remember to make sure holder is not slid in too far or push it back so it drops into the slot and seats correctly. A pain in the a$$ but the only problem with the camera.

[Rick Heitman]

Just saw the pic, and I am sure it is not vingetting. Go with the other answers