Botched negs, what did I do wrong?

dealy663 · Aug 2, 2005

Hello Everybody!

I'm sorta new to developing but have processed about 10 rolls of 120 and 35mm B/W film myself in the past few months. The roll I just developed last night turned out to have some major problems, based on the look, my guess is light contamination. On this roll of 120 it looks like about 6 of the exposures suffer from this problem. According to my log all of the problem exposures were shot with the same lens. But some of the frames shot with this lens don't appear to exhibit the problem.

Here is a link to a page showing two of the frames that I've scanned. I made no attempt at nailing the white and black points of this scan so ignore how flat the image is.

http://www.grandprixsw.com/photography/pub/August 2005/080105/index.html

These were shot on my old Koni Omega Rapid 200. The last time I used this camera with this lens everything seemed to be ok.

So my question is: Does this look like a camera problem, or more like I somehow let some light in while loading the film into the magazine?

Thanks in advance for any suggestions.

Derek

Canuck · Aug 2, 2005

Definitely a light leak. Just guessing but looks like you have a light leak in your magazine. Check your neagatives. If the light leak is across more than one frame, I would then guess processing, but if its at a similar location for the frames fogged, then a magazine problem. Just guessing, so YMMV

dealy663 · Aug 2, 2005

Follow up

It looks like the first and last frames of this roll aren't suffering from this problem. All the other frames have the same issue with only the lower left hand corner not being over exposed. However the degree of the light leak seems to vary from frame to frame, on some it isn't so strong.

Derek

john_s · Aug 2, 2005

dealy663 said:
.... However the degree of the light leak seems to vary from frame to frame, on some it isn't so strong.

Derek

The amount of light leaking in depending on how long between exposures, and the orientation of the camera to the sun. Just a conjecture.

dealy663 · Aug 2, 2005

I'm a little closer to isolating the problem now

Well I'm a little closer to figuring out what is going wrong. I just went back and reviewed one of my rolls from May and sure enough the same sort of light leak occurs on 3 of the frames. At the time I just discounted the problem because I was hand holding a filter in front of the lens and just assumed I didn't have things lined up.

Well after checking my log I see that I used the same lens on the roll in May as I used on this roll I shot last saturday. On the May roll the other frames look fine, and they were shot with my 58mm and 90mm lenses. The problem frames were shot with my 135mm lens.

On the roll that I shot last saturday all but one frame were shot with the 135mm lens. However there is one frame on that roll that was shot with the 135mm that is just fine (the first frame on the roll).

I'm quite perplexed about why this particular lens could becausing such a problem. I just put the lens on the camera and removed the film back looking for some sort of light leak but don't see anything.

Any ideas?

Derek

Nige · Aug 2, 2005

I had a light leak on a Mamiya 645 that only showed up if the film was left in the camera in the sun for a decent amount of time. Had me perplexed until I asked a repairman and he said if the extra density shows up outside the image area then it's almost certain the leak is the back, which was the case for me.

jjstafford · Aug 2, 2005

dealy663 said:
Well after checking my log I see that I used the same lens on the roll in May as I used on this roll I shot last saturday. On the May roll the other frames look fine, and they were shot with my 58mm and 90mm lenses. The problem frames were shot with my 135mm lens.

[...]

I'm quite perplexed about why this particular lens could becausing such a problem. I just put the lens on the camera and removed the film back looking for some sort of light leak but don't see anything.

Any ideas?

Derek

(First, I hope you appreciate what a fine lens that KO 135mm can be. It is a bit rare, too.)

As to the inconsistency of the occurence, a big factor is the stress on the camera caused by various things: using a tripod (or not using one), the way it is gripped, or if your lens has its own tripod socket. Gaffer tape the back's edges and be happy.

noseoil · Aug 2, 2005

I use black electrical tape on the back of my old C330f at times, if the film sits a while or if I'm in lots of sun at an angle with the back. Do the edges and see if it works. Tape is cheap, images are priceless! tim

gnashings · Aug 2, 2005

I think I just posted this in another thread - but it bears repeating: I strongly, strongly echo the sentiments about the light leaks and the fact that they are very tricky and dependant on many factors. These appear to be sourcing from the camera not from development, as they are in the same spot on both negs. The intensity can depend (or even not occur at all) on many factors already discussed here. Time to check out the gentelman with the seal kits!

Claire Senft · Aug 2, 2005

You may have a sticky shutter. Is the problem related to just one focal elnght, Load up a roll and test a few shots with each focal lenght. I would guess that this could be caused by shutter blades that are not closing.

Ed Sukach · Aug 2, 2005

Without seeing the film itself, it is difficult to diagnose. One question ... does the area of increased density extend beyond the frame itself into the margins where the imprinting is, and/or the space between frames? If not, I would suspect a sticky shutter blade. Open the back and look at the shutter in operation, especially at the slower speeds. This is not a perfect test, but it may be of use.

If it DOES extend into the margins, It would indicate a light leak, in loading, or when not being exposed. A good test of this would be to advance the film - NOT expose a frame or two, and leave the camera in bright sunlight for a periond of time. Block the lens, try another frame, using a lens cap or something, and process the unexposed film. A light leak would show up as an area of density on the unexposed frame.

Or ... Flare? Where was the sun, and was/ is the lens free from MAJOR (it would have to be really noticeable) scratches and/ or contamination?

JD Morgan · Aug 2, 2005

Use photo paper test strips to isolate it.

rexp · Aug 2, 2005

I wonder if the light leak occurs when you change the lens? If it occurs on frames where you inserted the dark slide & swapped lenses, then you could try a couple of tests. Put on the 135 lens BEFORE loading film, and go out and shoot the entire roll with that lens. If there is no fogging, then you could do the "hold it in the sunlight while inserting the dark slide" torture test. It could be the seals where the dark slide is inserted. I wonder, does your 135 lens have the rectangular rubber seal glued on the back? I could envision some trouble if this piece was missing.

Konical · Aug 2, 2005

Good Morning, Derek,

I use a Koni-Omega. A recent experience MAY be relevant.

A couple of months ago, I shot a partial roll at an event, then headed home (250 miles south) with the Koni hung by its strap facing forward in the passenger seat of the car. The lens cap was on; it was a bright sunny day. When I processed the film, there was some fogging on the last couple of frames I had shot. As nearly as I can tell (guess?), the fogging occurred because of a small light leak through the slot where the magazine dark slide fits. I did not have the dark slide in the magazine at the time. I have never previously had any such problem, but, then, I'd never previously subjected the camera to four and one-half hours of direct sunshine aimed almost exactly at the dark slide slot. I don't know if this is your problem, but it's worth checking out.

Konical

srs5694 · Aug 2, 2005

First, I'm not familiar with your camera, or with 120 gear generally, so if I say something that's ridiculous in that context, please just ignore it. That said, I do have a couple of points to make, based on my experience with 35mm cameras:

As rexp suggests, the leak could be associated with changing your lens, rather than with the lens itself. If the shutter isn't completely light-tight, changing the lens can expose it to much more light than would occur by just removing the lens cap, thus increasing the fogging compared to leaving the lens on at all times. To minimize the problem, change lenses inside or at least in the shade, and do it as quickly as possible. Even just turning your back to the sun when changing lenses can help.
You may be able to isolate the problem by using a flash in a dimly-lit room. Put the flash somewhere where you suspect the light leak to be, such as pointing into the lens opening when the lens is removed. Wrap the whole camera/flash assembly in a dark towel, leaving the camera back open so that you can see the area where the film normally resides. Then use the test button on the flash. If everything's wrapped properly, you should see very little light from the flash, except for any leaking area. (It may take a few tries to completely cover the camera, including all its edges; a small gap in the towel can leak enough light to swamp any leak around any in-camera leak.)

dealy663 · Aug 2, 2005

As far as the 135mm lens is concerned I haven't been able to appreciate how fine the lens is yet because I just got it and all but one exposure with the lens exhibits the light leak.... :-(

This is a total bummer because the lens looks brand new, not a mark is on it!

Derek

dealy663 · Aug 2, 2005

Hey wow thanks for all the good suggestions. I'll be checking things thoroughly for light leaks. The thing about all this that is particularly disturbing is that I just had the whole shebang serviced. All of my lenses, backs and the body were all just worked over to the tune of several hundred dollars.

Derek

dealy663 · Aug 2, 2005

Someone over on photo.net has suggested that one of the leaves in the shutter on this lens may be dragging and remaining open too long. Does this sound like a reasonable assessment?

Derek

jjstafford · Aug 2, 2005

dealy663 said:
Someone over on photo.net has suggested that one of the leaves in the shutter on this lens may be dragging and remaining open too long. Does this sound like a reasonable assessment?

Derek

It's a darned good suggestion. Now that I look again, the light contamination does seem to have a conspicuous optical pattern.

Julian Ferreira · Aug 3, 2005

As the gentleman with the Mamiya 645 mentioned, if the fogging extends past the frame lines... ie: is on the rebate edge. The fogging is not coming from the front of the camera ie: the lens. It would have to be coming from the back or handling ...

dr bob · Aug 3, 2005

I've never had a problem with light leaks on my KO Rapid. I check all my cameras at least twice annually by inserting a bare bulb flashlight (mine is a Mini-Mag Lite with the lens cover removed) into the body, first from the front with the lens out, then from the rear with the back removed and a lens in place. In a dark room it is fairly easy to detect leaks. I move the camera on all axis and look for pinpoints projected on the walls or ceiling.

Botched negs, what did I do wrong?

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