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View Full Version : Light leak with Wista 8x10 and Toyo holders



Chris CS
10-Dec-2011, 03:37
After working with a Toyo 45AII for a number of years I finally decided it was time to move to 8x10 and subsequently purchased a Wista 8x10 on Ebay.

Unfortunately (and this is new to me as a full time LF photographer) the first negatives I got back from the lab (and weeks of work) were ruined by terrible fogging.

After a day of testing I have identified the cause as a bad seal between the Toyo 8x10 holders and the camera back. With the camera outside in bright sunlight, looking through the front standard with a darkcloth over my head I can see a tiny amount of light seeping in between the rear standard and film holder all the way around. Being used to the flawless operation of the 45AII + toyo holders this seems absolutely ridiculous.

Is the Wista a shitty camera, does mine have big problems or are the Toyo holders a bad fit? Certainly a professional camera should be 100% light tight.

Has anyone had similar experiences?

Thanks in advance.

Jim Noel
10-Dec-2011, 08:51
This may sound ridiculous, but the only time I have observed this phenomenon with students occurred when the holder was being inserted from the wrong side of the back. With some cameras this is an easy mistake if the "ears" on the insertion end are not prominent. If the camera was owned by a lefty, this could be your problem.

J. Fada
10-Dec-2011, 09:28
Is it possible the camera is worn? I find it odd that light leaks all the way around the holder and not just in certain areas. You could also check if your holders are warped. I have seen warped plastic holders before, especially 8x10, although not Toyos. It could be possible that the camera back is warped as well. If you take off the spring part of the back you could lay a straight edge on the rails to see if they are flat. You could also check the connection between the back and the camera. I had a Kodak that leaked in this area years ago and it drove me crazy until I found it. Also check to see if the groove is deep enough to accept the tab on the holder to allow the holder to sit flat. I guess you could check this by looking from the insertion side. Also make sure that the spring has sufficient tension. I don't know if this has been any help to you but I wish you luck.

falth j
10-Dec-2011, 10:05
I am not familiar with the wista 8x10, but can relate to a 'new' 4x5 wista model that had similar light leaks around the film holder and the camera back.

I replaced the felt light seal material and that fixed the problem.

The hardest part was to find light seal material of the same thickness, which I ultimately solved by adding a shim of the correct thickness to raise the new and thinner light seal material to the same height as the old material.

Bob Salomon
10-Dec-2011, 11:00
Are you in the USA? If so Marflex is the Wista service center.

Chris CS
10-Dec-2011, 13:10
a) I am in New Zealand.
b) I am not inserting the holders from the wrong side.
c) They are new Toyo holders which I do not think are warped, but I will check them and the camera back with a straight-edge.
d) The springs on the back could use tightening/replacing but I do not think this would make the seal light tight.

The part of the camera back which the holder sits against is merely wood painted black - there is no felt. Is this normal for the Wista 810?


I will take pictures of the problem now.

Thanks for your help so far.

Michael Kadillak
11-Dec-2011, 11:30
I will tell you as a long term user or Toyo holders in 8x10 that it is not the holders as these are the cream of the crop in all respects. I have a Toyo 810m, a Calumet C1 and a Canham 8x10 camera and each of these cameras do not have any felt in the film holder area I would suspect because this is a critical tolerance area. I will tell you that all of these cameras (two metal and one wooden) operate without any hint of light leaks without a dark cloth of the camera in direct sunlight.

Here is what I would do. Put a holder in the camera back and in your darkroom with the lights off put a flashlight into the bellows of the camera and point it to the back of the camera and look for light leaks around the film holder. You should see zero light coming from the inside of the camera in this condition in the same regard as light could not come in from this point. I can't imagine a situation where the camera back would warp but this would tell you if this was the case. Also use this light to check around your bellows connectors to the frame or for that matter anywhere along the bellows. It may not have anything to do with the camera back. Let us know what you find. Good luck.

RichardRitter
11-Dec-2011, 12:33
Sounds like the holder is not seated right. Put the holder in then pull on the holder to make sure it is in the lock grove. if it is in the lock grove and you have a light leak the lock grove is not deep enough. One way of checking this is take the back off and look at the back on the inside side of the back, look to see if the holder is sitting against the back all the way around.

Michael Kadillak
11-Dec-2011, 19:32
Sounds like the holder is not seated right. Put the holder in then pull on the holder to make sure it is in the lock grove. if it is in the lock grove and you have a light leak the lock grove is not deep enough. One way of checking this is take the back off and look at the back on the inside side of the back, look to see if the holder is sitting against the back all the way around.

Richard makes an excellent point. I was assuming that your T Lock groove was properly aligned since I believe that you indicated that that you acquired a used camera. The odds that this T lock distance is "off" is remote since 8x10 is such a standard format. I also put credibility that the camera owner/user is intimately familiar with proper film holder insertion irrespective of format and would know when things are "off".

My instincts tell me that something is going on with the bellows because even if the rear springs were not at full strength, it would not result in the problems that have been described.

Chris CS
16-Dec-2011, 17:06
An update:

I took the camera to a tech who tightened the springs on the back along with fixing a couple of holes in the bottom of the bellows. Unfortunately I believe the bellows holes are a non factor and am certain light is leaking around the film holder. The tech denies this and he is the only one who still works on film cameras in my city so I am in a tough spot.

I've attached some images so you guys can see.

fogging_1.jpg
This was the worst fogged negative. In this case I had the dark slide out for perhaps 10 minutes while I waited for the clouds and light to be as i wanted and the wind to stop. You can see that the negative is not overexposed - despite being a super-contrasty scene the highlights are still well within the exposure, but the image has been fogged from bottom to top.

fogging_2.jpg
While not as bad as 1, it is still a terribly fogged and unusable negative. The dark slide was out for a shorter time (maby a couple of minutes) compared to image 1, which i think explains the lesser degree of fogging. Again you can see that the light has come from bottom to top (so from the top of the camera as the image is upside down.)

digital_of_image_2.jpg
I use a digital camera along with a incident meter to check my exposure. This was made seconds before the film image and the same exposure is used for both.

holder_in_camera_back.jpg
This is how the toyo holder is sitting in the back. You are looking at the top side where i believe it has leaked. You can see that it doesn't appear to be a good seal.

Bob Salomon
16-Dec-2011, 17:20
Why not try a sheet and see if he was right. If he was wrong bring the camera and the test sheet back to him.

Daniel Stone
16-Dec-2011, 19:14
why not insert the film holder into the camera, make sure its properly seated in the t-lock groove. Then, take a powerful handheld flashlight and from the lens end of the bellows, shine the flashlight around the edges to see if you can find any leaks. Do this in a dark(er) room to ease viewing of small light leaks, this should take no more than ~5mins or so, and will let you know if the t-lock groove's depth is the problem, or if you have another problem. I'm guessing you have some sort of pinholes in the bellows as well, since the outline of the holder's film retaining edges are quite clear and sharp.

2ndly. I'd NEVER leave the darkslide out for more than 15sec or so. Especially in bright sun. Assuming that you load your holders from the right, thats subjecting the light trap to 10mins of direct sun exposure. But 10min of the darkslide being left out, any time of day, IMO, is just asking for problems, real problems. Even if you you have a fully opaque darkcloth wrapped around the back of the camera...

-Dan

Michael Kadillak
16-Dec-2011, 22:15
I would send the camera to Richard Ritter for a diagnosis and an estimate for resolving the problem.

Greg Davis
17-Dec-2011, 11:21
Be aware that this can also happen from a light leak around the lens board, too. Check that it is seated and sealing properly to eliminate it as a suspect.

-Greg

Bob Salomon
17-Dec-2011, 12:11
So you are aware, Wista the only factory service center in the USA is Marflex.