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tom thomas
23-Jul-2014, 15:39
I just shot a roll of film through a 1950 Kodak 620 camera and find fogged areas on the negatives getting worse as the roll progresses. Admittedly this is MF film but you guys in LF offer great advice. Background. The film was expired in 02/2013, Ektachrome Pro 100. Sealed rolls made round trip to France in carry-on, which I'm told shouldn't hurt them as 100ASA. I used a double sealed dark bag, hand rolled the 120 spool onto a 620 spool to load in the French Kodak with f4.5, 100mm Angineux lens. Got 8 exposures at 2x3, scanned negs to positive image.

Area of light is rectangular, vertical, about midway in the pose, ie in center of field. It is only half height though, not from top to bottom so I'm wondering if it's a light leak or lens flare as the pro who developed the roll suggested. Here are a couple examples of what I'm talking about. The camera appears in good shape, no obvious damage, tears or small cuts in the bellows.

Since the light pattern appears in the bottom center quadrant, I assume the light is leaking in from the top of the bellows, or top of the back. All appears normal though.

Ideas? It's a nice compact camera with a real wide landscape image. For example, the Tulsa Driller is about 100 feet tall and I took the picture from about 30 feet from it. I'd like to use it at least for sample shots before committing to cost of 4X5 film and development with my Graflex.

The Driller photo is the 1st on roll, train is 3 or 4 and the horse meets car photo is 7 or 8.

thanx.


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tom thomas
23-Jul-2014, 15:41
Here is the camera, top view of the bellows.118822118823

ImSoNegative
23-Jul-2014, 18:15
it almost looks like you are getting some sort of reflection, bet its a bellows leak

Harold_4074
24-Jul-2014, 12:36
The lighting seems to be different in each picture, but the defects look to be nearly identical, so it probably isn't lens flare. The position of the defect within each frame seems to be the same (but you should check this) and frames 1 and 8 would be wound at substantially different radii on the spool so x-ray or thermal damage is probably out, too.

This doesn't leave many possibilities, and a light leak (bellows or camera back) are where you should look first. As I'm sure you know, the traditional bellows test involves a dark room and a light bulb inside the bellows. The easy way to check out the back is to load the camera, wrap everything but the bellows and lens in black cloth, and take it out in the sun for a while. You can even use printing paper for this if you are patient...

Daniel Stone
24-Jul-2014, 14:25
My bet is pinholes in your bellows. You shot these in HARSH, RAW SUNLIGHT. You can't really ask for more light than that, unless you're putting a strobe head right next to the bellows ;)

Take a small, but super bright flashlight, in a VERY dark room or closet, and shine the light into the corners of the bellows FROM THE INSIDE, pointing into the corners. Look at the bellows(do this operation while bellows are at full/normal extension), and note where the light leaks are. I use small pieces of white tape to mark the corners.

***On smaller cameras like this, I use a BORE LIGHT(yes, the kind you'd use to look down the barrel of a gun), as it has a 90 fiber optic bend, and is much smaller than my normal Surefire flashlight which can easily fit inside the diameter of the bellows on my larger LF cameras. My bore light is an attachment for my Surefire actually, but this light(below) is similar in style:

http://www.amazon.com/Browning-Microblast-Light-Pen-Adaptor/dp/B002RC1MHO

Once done marking said pinholes, I fill them in(from the inside) using liquid electrical tape(the BLACK stuff in the jar from the home store) and a small throwaway modeling paint brush to "paint" into the leaky corners/pleats. I then leave the repaired areas to dry, leaving the bellows fully extended for a full 24hrs, preferably 48hr, so the repaired areas can cure. The main trick I've found is to NOT overdo it, small amounts can go a long way. And repairing the bellows from the inside helps keep things looking pretty :)

-Dan

tom thomas
24-Jul-2014, 16:29
My bet is pinholes in your bellows. You shot these in HARSH, RAW SUNLIGHT. You can't really ask for more light than that, unless you're putting a strobe head right next to the bellows ;)

Take a small, but super bright flashlight, in a VERY dark room or closet, and shine the light into the corners of the bellows FROM THE INSIDE, pointing into the corners. Look at the bellows(do this operation while bellows are at full/normal extension), and note where the light leaks are. I use small pieces of white tape to mark the corners.

***On smaller cameras like this, I use a BORE LIGHT(yes, the kind you'd use to look down the barrel of a gun), as it has a 90 fiber optic bend, and is much smaller than my normal Surefire flashlight which can easily fit inside the diameter of the bellows on my larger LF cameras. My bore light is an attachment for my Surefire actually, but this light(below) is similar in style:

http://www.amazon.com/Browning-Microblast-Light-Pen-Adaptor/dp/B002RC1MHO

Once done marking said pinholes, I fill them in(from the inside) using liquid electrical tape(the BLACK stuff in the jar from the home store) and a small throwaway modeling paint brush to "paint" into the leaky corners/pleats. I then leave the repaired areas to dry, leaving the bellows fully extended for a full 24hrs, preferably 48hr, so the repaired areas can cure. The main trick I've found is to NOT overdo it, small amounts can go a long way. And repairing the bellows from the inside helps keep things looking pretty :)

-Dan
Thanx Dan and all. You were right about harsh, raw sunlight. Especially the last ones of the buggy and car. Literally high noon, standing in the sun, which then turned out to be a good test of the camera. Photo 1 I was standing in the shade shooting out into sun so the flare isn't quite as evidfent. The bellows looks great but I'll definitely run thru the tests and repair recommendations from you guys. Then lens seems to be too nice to waste just because a bit of repair is needed. I'll re-foam the seams too. Probably twisted thread though but I have a kit that includes foam, thread, felt too.

tom thomas
27-Jul-2014, 16:14
it almost looks like you are getting some sort of reflection, bet its a bellows leak

I can't find a bellows leak. Went in a dark room, used bright flashlight in bellows area, no evidence of light leak or pinholes anywhere. Bellows is clean, supple and like new. I'd treated it earlier with a leather conditioner. Tried several times after opening and closing camera to flex the bellows. Made sure the lens/shutter is tight on the front frame, checked for hanging aperture leaf. Shutter is working fine, apertures snappy as expected.

There isn't any foam/felt/thread in the back cover door so can't replace that.
The light leak gets progressively worse on frames 5, 6, and 7 with the darker stripe down the edge before the overexposed area. The stripe isn't evident on frames 1 thru 4, nor on frame 8.
I do have the little film number window covered with the attached metal tab and open while winding to the next number. I closed the tab before shooting as I've read that light can leak in there. Doesn't seem to be.

I'm wondering if the light isn't leaking in around the Wind knob somehow, as the top half of the frame is getting the "flare effect, as is the leading edge of the frame as I winds. All looks good though around the knob. I put light on it in dark room and don't see any leakage either. I can unscrew the Wind knob easily, tested it without the knob so I could shine light directly into the frame hold around the wind mechanism. I did just find that the tensioner spring in the takeup spool area is broken off and a previous owner compensated by bending edge of the body on the bottom side of the area. Light seems to be coming in from top so don't think that the cause.

Ideas?

ic-racer
27-Jul-2014, 18:36
Yes and yes: the film has been damaged by a light leak.

John Koehrer
28-Jul-2014, 19:27
You could make a washer from a circle of felt & put it under the knob. It would eliminate one suspect area.

Harold_4074
28-Jul-2014, 20:46
If you are up to manipulating things in total darkness, you might lay a piece of film (or paper) across the film plane, with backing paper or velvet between it and the pressure plate. Take the camera out into bright light, and then go back into total darkness for removing and developing the film. This may tell you if the problem is associated with film on the roll or with light getting into the bellows area (although you have already checked that by the light bulb method).

The similarity of the flare patterns on these images, and the sharp cutoff on the right-hand sides, make me doubt that it is occurring on the film roll. The "hottest" spot is at the upper right of the third frame from the left; would you consider putting a rolled piece of printing paper inside the bellows in order to see if you can "intercept" light on its way to the film?