Black marks / light fog on negatives. What caused this?

[nicholasnicholas]

See attached pics, it's a test roll from a Nikon F3 with different lenses. The black mark / hazey edges of some shots is concerning. Could this be light leaks / bad seals or a mechanical issue going on?

There was a motor drive attached to the Nikon F3 that was removed on / off during this test roll if that could do it?

(Nikon F3, 50mm Pre AI lens, MD4 Drive, Kodak Ultra)

Thanks!

 

[koraks]

Doesn't look like a leak to me. Something is obscuring the film during exposure. No fingers in front of the lens?

 

[nicholasnicholas]

Doesn't look like a leak to me. Something is obscuring the film during exposure. No fingers in front of the lens?

No finger over lens that i'm aware of.
Here's a link to a video of the aperture blades on the lens I was shooting. Could this cause the marks?
Aperture blade inconsitent

Something about a "a slow up or early down going mirror." was mentioned elsewhere if that makes sense as a cause?

 

[nicholasnicholas]

Here are some other shots, same day, same lens. The settings were basically the same, yet no black mark or blob...

 

[koraks]

Could this cause the marks?

Nope. That would just cause over- or underexposure and slightly funny bokeh shapes. The latter is probably unnoticeable. The former may be an issue at small apertures.

Something about a "a slow up or early down going mirror." was mentioned elsewhere if that makes sense as a cause?

I don't expect so; the blocked area would have a straight edge to it. This is decidedly curved.

Given the fact that it's very blurry, it's likely to be close to the lens.

You mention having tried different lenses on this camera. Does the problem occur with more than one lens?

You don't have a hood installed on the lens that happens to be deformed or fitted incorrectly?

 

[nicholasnicholas]

Nope. That would just cause over- or underexposure and slightly funny bokeh shapes. The latter is probably unnoticeable. The former may be an issue at small apertures.



I don't expect so; the blocked area would have a straight edge to it. This is decidedly curved.

Given the fact that it's very blurry, it's likely to be close to the lens.

You mention having tried different lenses on this camera. Does the problem occur with more than one lens?

You don't have a hood installed on the lens that happens to be deformed or fitted incorrectly?

Another post eons ago talked about the "braking mechanism" for the shutter as a cause. The thread was never resolved, so I don't know if that is or isn't relevant here?
Link to Other post

 

[nicholasnicholas]

Another thought, could holding the DOF button and taking the shots be doing this?

 

[Don_ih]

Can you check the shutter operation with the back open? Or with no lens on the camera? Set the shutter speed to 1 second?

 

[koraks]

Another post eons ago talked about the "braking mechanism" for the shutter as a cause. The thread was never resolved, so I don't know if that is or isn't relevant here?
Link to Other post

Hm. Yes. Perhaps. In the example in that thread, there is a shape that I could interpret as a mirror that's halway through it's travel, and the corner of the mirror is casting a shadow onto the negative. The distance from the negative would be appropriate for the degree of blurriness.

 

[nicholasnicholas]

Here's a contact sheet from the roll to get a look at the neg proper and the borders etc. 2 shots with the black blur / mark are dotted in blue. Don't know if this helps.

Any advice on a proper test to rule things out, i'm all ears.

 

[Don_ih]

Bottom left, something pretty odd going on. What happened there?

 

[koraks]

Well, it really does look very comparable or identical to that photo.net thread you found. If that was the mirror somehow remaining in the optical path, which does sound plausible, then it's time to do a check up of the mirror mechanism. You could consider posting a thread about it in the Camera Repairs forum or the 35mm Cameras forum; perhaps some people with knowledge of the F3 will chime in and offer their advice.

What happened there?

Looks like a major transportation issue combined with multiple exposure of the same scene.

Sounds like this camera is due for a CLA.

 

[nicholasnicholas]

Well, it really does look very comparable or identical to that photo.net thread you found. If that was the mirror somehow remaining in the optical path, which does sound plausible, then it's time to do a check up of the mirror mechanism. You could consider posting a thread about it in the Camera Repairs forum or the 35mm Cameras forum; perhaps some people with knowledge of the F3 will chime in and offer their advice.



Looks like a major transportation issue combined with multiple exposure of the same scene.

Sounds like this camera is due for a CLA.

That was a huge overlap of images with the motordrive attached. The film definitely stopped transporting.
Works fine without the MD otherwise from the rest of this test roll.

I can check out the other forums for some insight for sure

 

[snusmumriken]

Forgive me for the obvious, but could there have been anything else that got in front of the lens? It’s just that the OOF blob looks so very like what happens if you get a flap of something in the way, whereas I’d expect the mirror to make a sharper outline.

 

[Ian C]

The Nikon F3 uses a relay mirror for the photocell of the light meter (attached to the rear of the reflex mirror holder). See page M11 and M13 in the F3 repair manual in the following link.

[F3 owners might want to save a copy of this file for further reference.]

http://ss-it.de/data/servicemanuals/F3 (V. 1).pdf

I suspect that the relay mirror intermittently intrudes into the light path between the bottom of the scene and the area along the top of the film gate casting its shadow upon the film. If so, this would show along the bottom edge of the developed film frame. That’s what we see in the some of the photos displayed by the originator of this thread. (The repair manual refers to it as the "metering mirror.")

This could happen if the mirror sometimes rebounds upon striking the stop pad surrounding the viewing screen mount, possibly sticking in this position as the shutter cycles. It could also happen if the mirror occasionally fails to fully come to rest against the pad. That this happens intermittently suggests sticking due to dried or oxidized lubricant.

Some of the frames I viewed also seemed to exhibit differential exposure across the long dimension of the frame. That would not be related to the relay mirror. This seems to be the case in the two photos shown in post #4. That might also be the case with negative frames #22, 23. If so, this problem is likely related to the uneven travel of one of the shutter curtains. This too can be intermittent.

The film transport problem is a separate issue. As others have commented, this camera needs the attention of a qualified technician experienced in the servicing of the Nikon F3 camera.

 

[MattKing]

Forgive me for the obvious, but could there have been anything else that got in front of the lens? It’s just that the OOF blob looks so very like what happens if you get a flap of something in the way, whereas I’d expect the mirror to make a sharper outline.

+1
Cases, straps, jacket sleeve????

Another thought, could holding the DOF button and taking the shots be doing this?

Yes, if while holding the DOF button you are accidentally blocking a bit of the light path.

You wouldn't be the first to do this, nor will you be the last!

 

[Sirius Glass]

Something is blocking the lens field of view, as @MattKing stated: camera strap, camera case [who uses those these days?], jacket, long hair, finger …

 

[Nicholas Lindan]

Just from looking at the negs I would have guessed a curl of torn film is trapped between the mirror and the shutter.

To reiterate - what do you see with the lens removed and the shutter set to B?

 

[nicholasnicholas]

Just from looking at the negs I would have guessed a curl of torn film is trapped between the mirror and the shutter.

To reiterate - what do you see with the lens removed and the shutter set to B?

Heres a look at the inside - all seems fine. The foam on the second mirror is crumbly, but not sticky.

 

[nicholasnicholas]

The Nikon F3 uses a relay mirror for the photocell of the light meter (attached to the rear of the reflex mirror holder). See page M11 and M13 in the F3 repair manual in the following link.

[F3 owners might want to save a copy of this file for further reference.]

http://ss-it.de/data/servicemanuals/F3 (V. 1).pdf

I suspect that the relay mirror intermittently intrudes into the light path between the bottom of the scene and the area along the top of the film gate casting its shadow upon the film. If so, this would show along the bottom edge of the developed film frame. That’s what we see in the some of the photos displayed by the originator of this thread. (The repair manual refers to it as the "metering mirror.")

This could happen if the mirror sometimes rebounds upon striking the stop pad surrounding the viewing screen mount, possibly sticking in this position as the shutter cycles. It could also happen if the mirror occasionally fails to fully come to rest against the pad. That this happens intermittently suggests sticking due to dried or oxidized lubricant.

Some of the frames I viewed also seemed to exhibit differential exposure across the long dimension of the frame. That would not be related to the relay mirror. This seems to be the case in the two photos shown in post #4. That might also be the case with negative frames #22, 23. If so, this problem is likely related to the uneven travel of one of the shutter curtains. This too can be intermittent.

The film transport problem is a separate issue. As others have commented, this camera needs the attention of a qualified technician experienced in the servicing of the Nikon F3 camera.

This is an interesting comment, thanks. Would old foam (dry and crumbly, not sticky) potentially cause this mirror bounce back and coming into the frame?

Aside from a CLA (possibly quite expensive here in Aus) any tips on what I could do to narrow the possible cause?

Thanks for the input so far in the comments!

 

[250swb]

My vote is for a camera strap, if your eye has gone off-centre of the viewfinder maybe you didn't see it, and it's not impossible to be looking so hard at the subject you see past the obstruction, like you do when looking at the road ahead and you don't notice the Rolls Royce mascot on your hood.

 

[nicholasnicholas]

SO! A 2nd test roll back and there are no mysterious black marks like the previous shots. I think, and awkward to say, it may have been a finger/strap/anomaly in the last roll. Nothing like this on the second roll, varying speeds. It likely would have shown up at least once if it was the mirror etc?

If that's good, woo-hoo!

The next step is a light tight body.
I have redone all the back door seals.

Do any of these leaks look like they're coming from elsewhere on the body?

The appearance is sort of a red / brown fog at the egdes and some trouble in bright light / the sun.

Thanks for all the input everyone.

 

[nicholasnicholas]

As an aside, this F3 80/20 metering makes shooting landscapes with harsh shadows a challenge to meter for!

 

[Don_ih]

It likely would have shown up at least once if it was the mirror etc?

It didn't happen every shot in the last roll. And, if the camera had been sitting around unused, maybe exercising it will make it happen less frequently. But it probably was that mirror - the profile is too consistent with other examples.

I can't see any light leak in your photos - maybe it's the screen I'm viewing them on. There doesn't appear to be any evidence of a light leak on the photo of the negative (in the unexposed areas).

 

[nicholasnicholas]

It didn't happen every shot in the last roll. And, if the camera had been sitting around unused, maybe exercising it will make it happen less frequently. But it probably was that mirror - the profile is too consistent with other examples.

I can't see any light leak in your photos - maybe it's the screen I'm viewing them on. There doesn't appear to be any evidence of a light leak on the photo of the negative (in the unexposed areas).

When you say consistent, do you mean with other people (and their posts) having had the same thing?

The light leak or hazy edges are prominent on the 2nd photo, the red-ish edges (also an accompanying neg) - A number of shots have that sort of thing.