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Trainboy
22-Oct-2010, 12:36
Hey everyone, I've been having trouble with my new 4x5 camera and this forum looked like the best place to ask for help. My problem is that I've got a light leak and can't seem to find it...it's a toyo-view deluxe monorail camera, and I bought it months and months ago but have had absolutely no luck using it! I know the light leak isn't on the film or the holders due to extensive experimenting, but I can't find any holes in the bellows and I'm not sure where else to look or how to go about it. I've attached a photo taken with the camera to give you an idea of where I could start.
Thanks!

David Woods
22-Oct-2010, 12:59
Hey everyone, I've been having trouble with my new 4x5 camera and this forum looked like the best place to ask for help. My problem is that I've got a light leak and can't seem to find it...it's a toyo-view deluxe monorail camera, and I bought it months and months ago but have had absolutely no luck using it! I know the light leak isn't on the film or the holders due to extensive experimenting, but I can't find any holes in the bellows and I'm not sure where else to look or how to go about it. I've attached a photo taken with the camera to give you an idea of where I could start.
Thanks!

From the picture, it looks like the film holder is not sitting flush on the bottom edge, I have the same camera, and I used to have the problem, and then I realised you must push the film holder in tight. Or maybe the spring back is not holding the film holder in tight.
David

Gem Singer
22-Oct-2010, 13:14
If we could see the edges of the film, including the code notches, it would make the diagnosis easier.

However, since you are certain that the film and the holders are okay, and the problem is in the camera, judging from your picture, it looks like the film holder is not seating properly, and light is leaking in at one corner.

Check to make sure there is no obstruction, or if there is a piece of felt sealant missing from around the opening in the back where the film holder seats.

One other thing to check, if the camera has an interchangeable bellows, is to make sure the bellows is properly attached to the rear standard.

Jack Dahlgren
22-Oct-2010, 13:27
Hey everyone, I've been having trouble with my new 4x5 camera and this forum looked like the best place to ask for help. My problem is that I've got a light leak and can't seem to find it...it's a toyo-view deluxe monorail camera, and I bought it months and months ago but have had absolutely no luck using it! I know the light leak isn't on the film or the holders due to extensive experimenting, but I can't find any holes in the bellows and I'm not sure where else to look or how to go about it. I've attached a photo taken with the camera to give you an idea of where I could start.
Thanks!

Since the light is showing up on the bottom right, look at the top left. Putting a light inisde the camera in a dark room is an easy way of seeing what is going on.

Trainboy
22-Oct-2010, 13:50
Thanks for the tips! It didn't occur to me that the holder against the camera might not be sealing the camera against light, I'll take a look.

Ken Lee
22-Oct-2010, 14:49
If the camera has interchangeable bellows - and you took them off and replaced them again - then perhaps you didn't snap them back on securely.

ki6mf
22-Oct-2010, 15:26
leave the lens on the front extend the bellows as far apart as possible, remove the ground glass and shine a light inside. Do this in a dark room, Hallway or bath with no windows at night is good. Also check if there is a baffle inserted in your rear standard that may have been worn down.

Ross Chambers
22-Oct-2010, 23:18
If the camera has interchangeable bellows - and you took them off and replaced them again - then perhaps you didn't snap them back on securely.


Yep, I've done that with my Toyo-View 45CX (the entry level model)

Now I check the lens standard bellows connection closely every time, as I usually separate the two standards for storage.

Regards - Ross

al olson
25-Oct-2010, 09:02
Have you had any success curing the leak? As Gem Singer noted, it would be helpful to check the rebate. If the rebate is exposed, then it is likely that the exposure happened while the film was out of the holder.

Otherwise ...
The problem, as stated by others, is likely improper seating of the holder. You indicated that you have done extensive testing. From that statement, I assume that the leak is repeatable and not a one time occurrence.

That raises the question of how often? Nearly every time? Under some conditions the leak will not be apparent because of the direction and/or strength of the ambient light, the short time that dark slide is out of the holder, etc. Is it more obvious during longer exposures?

What kind of holders are you using? Grafmatics are very easy to displace because of the vigorous action to work the dark slide and the shuffle feature so I always use the Grafloks for them. Some double-sided holders have a non-standard placement of the ridge that fits into the notch on the camera back.

Also as the felt wears down, sometimes the holder will abut against the edge of the back without sliding all the way in. However it will feel as though it is in place.

Finally, examine the back for felt light traps. Are they worn? Are they missing? I had some that were ruined. I replaced them with strips that I cut from a piece of suede purchased from Tandy Leather.

Let's hear your results.

Bernard Kaye
25-Oct-2010, 13:21
Light coming through the lens is inverted; light leaking through a gap in film holder-camera body is where it is, it is not inverted, it is not an optical image.

Jack Dahlgren
26-Oct-2010, 20:06
Light coming through the lens is inverted; light leaking through a gap in film holder-camera body is where it is, it is not inverted, it is not an optical image.

A light leak showing up at the bottom of the image comes from the top of the camera. This is because the image is inverted so the bottom is at the top. The image shown indicates that light is coming in through the top of the camera.