Light leaks from red windows in 1930s cameras

[hadendowa]

Hi, I'm new to APUG, so I'm not sure whether this is the correct forum for my query, but here goes: I've just bought a 1930s Zeiss Ikon Ikonta A for 120 roll film, and I'm concerned that the red number windows, which have no shutters on this model, may cause problems with panchromatic film. Are there any makes of 120 panchromatic roll film with sufficiently opaque backing paper to avoid this problem? I don't want to modify the camera. Thank you!

 

[Bob-D659]

Black electricians tape makes a very good temporary shutter for the red window.

 

[wiltw]

But then how would you know that you have advanced the film far enough, to the next frame?!

 

[guitstik]

peel it back and re-stick it, simple.

 

[MattKing]

Painters tape will probably do the job as well, and is easily peeled and replaced.

But I would first try the camera with an ISO 400 film to see if you need to worry. Use it on a sunny day, and make a point of letting some sun hit the window for a moderate period of time.

The backing paper on the Kodak films I use is quite opaque.

 

[brucemuir]

I've had a window leak on an old Yashica A TLR but I had my back to the sun a good bit and wasn't aware of the issue back then.

Matt's suggestion about testing with some 400 speed sounds like a good one. I'm sure the ruby-lith can fade so it's probably a good idea.

 

[ntenny]

I wouldn't worry too much about it---when I've accidentally left the red window open on my folders, I've never had a problem. I think backing paper is plenty opaque enough unless you're subjecting the window to very bright light.

But if in doubt, it certainly can't hurt to tape a "shutter" over the window. I'd use a piece of cardboard under the electrical tape, just to avoid getting sticky goo on the window itself.

-NT

 

[Bob-D659]

If you have a steel back on the camera, a fridge magnet might work as well.

 

[R gould]

I use a lot of folders, from 1938 to the 50's, and often leave the ruby window un shuttered with 400 film and have yet to have a light leak,Richard

 

[Mike Wilde]

I have taped a layer of rubylith inside a 1914 era box camera where the red window plastic's red dye had faded.

 

[Hikari]

I would not worry until you prove it is a problem. The paper backing on roll film is certainly opaque enough to stop light, otherwise you could not load the roll in daylight.

 

[DWThomas]

I ran a light leak test on my Perkeo II last fall and among other things, left the red window cover open and facing direct afternoon sun. After a fifteen minute exposure of a blank frame on Tmax 400, I could find no evidence of any effects. I have heard that with some cameras, it is possible for light to bounce around between the back and the pressure plate inside the camera and get to the front of the film, but in my single test, I saw no problem. Of course, 15 minutes is not eight hours at the beach, I suppose some sort of flap isn't a bad idea.

If you could find a thin, slightly springy opaque material, you could tape a movable flap over the window. Orient it so in normal camera position, the taped side is up, then just lift the other edge to check the window.

 

[hadendowa]

Thank you everyone! I kept checking my "Notifications", which stated that there was nothing in my Inbox, until I had the bright idea of actually checking my original post - when I found the replies! Just shows the extent of my ignorance regarding how Forums work... Please accept my apology for not having responded sooner.

The camera arrived in today's mail, and it's a beauty, in superb condition, apart from fungus in the lens, which is otherwise near-pristine. At some stage, I'll have it serviced. It has the remains of tape adhesive around the red windows, so some previous owner has given Bob-D659's suggestion a try.

I'll give it a go with some 400, to check whether I'll need to use the tape method (fridge magnet won't work, since the body is of aluminium alloy) since I'd prefer not to risk damage to the leather.

It's a very compact camera, virtually identical in size when closed to my 1950 35mm Zeiss Contessa, but noticeably lighter.

 

[guitstik]

I wouldn't worry to much about fungus in the lens unless it is excessive. I have several lenses that I was able to pick up cheap because of fungus but they still take great pics. I have been known to expose some of the lenses to UV light for a period of time to kill off fungus.

 

[hadendowa]

Thank you, guitstik. The fungus is relatively light. Do you mean that you've exposed the lenses to bright sunlight, or does it work with ordinary daylight? I'm reluctant to expose the camera (which has a non-detachable Zeiss f3.5 Tessar) to sunlight for any length of time, in case it damages the morocco leather covering.

 

[bblhed]

I do have a tip for you that I didn't see posted, make sure that the backer plate that holds the film against the slides on the bellows is doing it's job and is still springy, in cameras of that vintage they were sometimes made of Brass and can take a set over time, you may need to just give them a little tug to be sure they are holding the film correctly. That was the biggest ruby window light leak problem I had until I figured it out.

I use the electrical tape window cover as well, I do about 1 and a half turns of the winding key and then look to get the number into place, I also shade the window with my body as well. No problems any more.

 

[Ian Grant]

This is probably the key to the issue.

I use a Gaoersi 6x17 and that has a clear window, very much larger & no red filter and I get no problems even when I've forgotten & left the cover open and I'm shooting in very bright sunlight, meters virtually at it's highest.

My two pre-WWII Rollex roll film backs have a felt shield that acts as a baffle to prevent light spread sideways from the frame counter widows.

I've just looked closely at my Ikonta 521, that has felt seals as well, they were OK but the pressure plate was a bit weaker than my other cameras.

My experience with velvet/felt seals on older LF cameras is it just flattens over time & use and can become quite ineffective. On roll film cameras these felt/velvet seals are designed to stop light passing underneath the pressure plate which has holes in it coinciding with the counter windows.

So I'd suggest look closely at these as well as the pressure plate.

Ian

I do have a tip for you that I didn't see posted, make sure that the backer plate that holds the film against the slides on the bellows is doing it's job and is still springy, in cameras of that vintage they were sometimes made of Brass and can take a set over time, you may need to just give them a little tug to be sure they are holding the film correctly. That was the biggest ruby window light leak problem I had until I figured it out.

I use the electrical tape window cover as well, I do about 1 and a half turns of the winding key and then look to get the number into place, I also shade the window with my body as well. No problems any more.

 

[DarkroomExperimente]

I love the refrigerator magnet idea!

I had just taped a piece of black cardboard over the window of my spiffy new Agfa/Ansco B2 cadet that I just cleaned up

adding a magnet to the cardboard was the perfect touch!

 

[ntenny]

Well, I guess I brought myself bad luck by commenting on this subject; I just got a roll of slide film back, taken with a 1930s Wirgin folder, and there are noticeable light leaks at the edge of some frames from the red windows!

I've used this same camera a zillion times in much brighter conditions without a problem, so I suspect I loaded it just a little off alignment or something like that. (The light looks like it bled around the edge of the backing paper rather than "burning" through it.) I need to eat my words about *never* having had a problem, though.

-NT

 

[Ian Grant]

Nathan, check my comments about the felt seals below the pressure plate.

Ian

 

[ntenny]

Nathan, check my comments about the felt seals below the pressure plate.

No seals on this one. Interestingly, instead of circular holes, the pressure plate has U-shaped cutouts that go all the way to the edge---an economy measure, I suppose; if I keep having problems, maybe I should attach a strip of felt or velvet along that edge.

-NT

 

[glbeas]

Well, I guess I brought myself bad luck by commenting on this subject; I just got a roll of slide film back, taken with a 1930s Wirgin folder, and there are noticeable light leaks at the edge of some frames from the red windows!

I've used this same camera a zillion times in much brighter conditions without a problem, so I suspect I loaded it just a little off alignment or something like that. (The light looks like it bled around the edge of the backing paper rather than "burning" through it.) I need to eat my words about *never* having had a problem, though.

-NT

That could just as easily have been from the roll not winding tight enough on the takeup reel. Many cameras have a spring that drags the back of the takeup roll to alleviate this problem.