Diagnosing underexposure with an F2

ChristopherCoy

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A couple weeks ago I picked up a silver F2A along with a 50mm f2 lens. I ran a few rolls through it and noticed a problem upon development. There is a large number of frames that had barely anything on them, or were so under exposed that the negatives were blank.

I know for sure that this is either a meter problem, or a lens problem, but I'm not sure which. I'm leaning toward it being a lens problem, because all of the frames that were taken with my 105 2.8 D lens came out superb. And I did have some frames taken with the 50mm that developed just as nice as those taken with the 105.

The reason that I believe it may be a lens issue is that I've noticed that the notch at the back of the lens barrel can sometimes slide past the meter coupling and not engage it. I've made it a point to always check that now. The weird part is that when I metered the frames that were blank, I remember the needle being in the "correct exposure" position.

Could I potentially be looking at some failing CDS cells?

Any thoughts on the matter? What else could I be looking at here?
 

Huss

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Blank suggests a shutter issue. I'm assuming that you're experienced enough to know the general ball park for an exposure, and the meter just fine tunes that. Even if you are way off, you will see something on the film.
If the lens was acting up, that would mean in your scenario that it is not stopping down so overexposed pics. Because if it did stop down but was not actuated with the exposure, you will see a permanently very dark image in the VF.

With my Zenits, unless i wind the film advance with vigor to the end of the stroke, it does not actually make an exposure, but sorta clicks like it has. Perhaps your Nikon is (also) doing this.

I would attach what you think is the offending lens, open or take the back off, and just dry fire it at different shutter/aperture combos while holding it to a light source to see if the behaviour seems correct.
 

MattKing

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Over-exposure due to a lens problem would be understandable - a lens that isn't stopping down properly at the time of exposure.
But under-exposure due to the lens would normally be accompanied by a too dark viewfinder.
Unless the aperture set on the lens isn't being properly communicated to the camera body.
 
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ChristopherCoy

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MattKing said:
Unless the aperture set on the lens isn't being properly communicated to the camera body.
Click to expand...

Viewfinder was never dark. It was morning light, overcast, and foggy, but I could see well enough. Upon development, the entire set which amounted to about half the roll was severely underexposed. I know that there was some exposure because the sky and 1 cow's head was faintly visible on the negative. The rest were just blank.


My other thought was if this was a non-AI lens that was modified by someone other than Nikon, and I should be using "stop down" metering techniques. Is this a possiblity?

The only thing that I can attribute this to right now is the notch slipping past the meter coupling and I just didn't notice it, and thought I was metering correctly. I'll have to see if I have the same issues with this next roll.
 

removed account4

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might suggest you take it to a repair person for a CLA, the camera is probably 30 years old ( lens too ) and could use an overhaul/ TLC.
you can open the back with the lens on the camera, no film and fire the shutter at all speeds from high to low and you will see if the shutter works.
sometimes people sell stuff and don't really say why they are "really" selling stuff ...
 
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ChristopherCoy

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It's already scheduled for service with Sover Wong next year.
 

MattKing

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Do you have notes or recollection what the exposure settings were for the problem negatives?
Were they somewhere close to "Sunny 16" or were they really different?
When working in daylight, I always have "Sunny 16" at least in the back of my mind, and if I am testing something new, "Sunny 16" is probably closer to front of mind.
 

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My F2 had a slow speed escapement problem and everything below 1/60th was extra long or the mirror hung.

I pulled it, cleaned it and it's fine. F2s are of the age it should be done anyway.
 

Chan Tran

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I would vote for the shutter problem. If it's the meter problem and it's that much off one should know that the settings aren't right for the lighting condition. As for the aperture it may stick an stuck open thus causing over exposure not under exposure. I would say the shutter is too fast or capping. More likely capping.
 
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ChristopherCoy

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I really believe they were in the 5.6, 1/250th range.
 

Horatio

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Have you dry-fired the shutter at different speeds (with the back open) to check it's working consistently? I'd try that before another roll of film.
 
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ChristopherCoy

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Kino said:
My F2 had a slow speed escapement problem and everything below 1/60th was extra long or the mirror hung.

I pulled it, cleaned it and it's fine. F2s are of the age it should be done anyway.
Click to expand...

Both of mine are going to Sover. I just got his reply stating that my booking was changed to two cameras. I should only have 10-12 months left.
 
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ChristopherCoy

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Horatio said:
Have you dry-fired the shutter at different speeds (with the back open) to check it's working consistently? I'd try that before another roll of film.
Click to expand...

I did that before I bought it. I went through every shutter speed with the back open to make sure that the shutter looked relatively correct.
 

mshchem

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Open the back, set the shutter to bulb set the aperture to f 8. Look through the back to see if the lens is stopping down. Like was said overexposure makes sense if the aperture is at fault. I've used F2 bodies since 1973, a couple years ago I had (a F2A) electrical fault. Current was not reaching the finder. Batteries were good, some sort of gizmo in the body gave out. I never use the meter, I gave the body to a friend. That's the only problem I've had with a Nikon F, F2, F3 or F5.
I would use your money for film.
Worst F I've ever had, I paid 25 bucks for. Plain prism that had the outer shell of the finder torn off. The person used silver colored Aluminum tape to cover the glass pentagram. Worked great! I sold it to a colleague, he's still got it. Boo Ya
 

Arvee

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Is the underexposure across the entire frame? If only affecting a portion of the frame or so, it is likely caused by shutter capping. I have a Canon FTbn that capped on 250, 500 and 1000 and caused severe underexposure. Open the back and check the higher speeds and see if (with the lens set at max aperture) the exposure is uniform across the fully open aperture. The Canon was completely obvious as the lens opening was very dim for 80% of the opening and was relatively bright for the last 15-20% (but not all the time; about half the time the shutter operated correctly).
 

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ChristopherCoy said:
It's already scheduled for service with Sover Wong next year.
Click to expand...
I'm sure Sover Wong is great ( to be honest I've never heard of them ) but if you actually want to use it you should send it to someone else, cla is typically the chain of events after buying any used gear (before its even used) ... that's crazy waiting a year, I can't imagine waiting 10-12months to have something CLA'd. maybe I'm just spoiled I have 2 excellent repair people within a few minutes of my house... and even in the go-go 80s when every pro in town had 8 bodies and 12backs and their whole stable of gear being maintained along with every institution in town ( art schools photo tech schools &c ). never took more than a few weeks not months

good luck !
 
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ChristopherCoy

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I chose to send them to Sover after seeing everything that he does to them beyond a CLA - like adding LED's to the finder to make the shutter and aperture easier to view, or rebuilding the resistor ring, or replacing CDS cells. Additionally, all he handles is F2's so I felt like with his knowledge and stock of parts, he was the best choice for what I'm wanting.
 

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good luck with that.
can't imagine doing all that to a beater Nikon
but what do I know I don't use nikons or pimp out my ride ...
hope after you trick it out that you actually use it ..
 
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ChristopherCoy

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jnantz said:
can't imagine doing all that to a beater Nikon
Click to expand...

Neither one of mine are beaters. The silver body only has one or two minor scuffs near the tripod mount, and the black body that @SchwinnParamount sent me only has minor brassing near the strap lugs. Both of them are at last a "9" with regards to condition. I wouldn't be planning to pay Sover's prices for beaters.

John sent me the black body in February, and since then I've developed more rolls of 35mm film, than I did all of last year combined. I carry both bodies with me everywhere I go. The silver body with the 50mm F2 stays around my neck, and the black body with the 28mm F3.5 stays in my bag. Since the DP-11 allows me to use my "D" lenses, I now carry the 105 2.8 Micro, and the 24mm 2.8 with me as well. Anytime I leave my desk at work, or get off the boat, I have a camera with me. I've actually been feeling pretty guilty because I've been shooting these two F2's so much that my RB67 is getting ignored.
 

removed account4

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ChristopherCoy said:
Neither one of mine are beaters
Click to expand...
its just an expression for a 40+ year old camera.
ChristopherCoy said:
Both of them are at last a "9" with regards to condition.
Click to expand...
as you have seen cosmetic condition means absolutely nothing when a 9 or 10 underexposes all your film
and you have to send it away to have all that work done on it..

glad you are shooting, I don't know anything about any of the lenses &c that you are talking about don't do Nikon stuff . glad its working for you!
im off to get work done on my car ( its old but works, no street fx or header exhaust ) and for the first time in a long time going out with a camera.. I'll be using a Pentax k1000, not very impressive.. no neon lights, bling. I did manage to have the top plate repaired about 20 years ago, I had duct tap on it for the longest time.
 
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ChristopherCoy

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jnantz said:
as you have seen cosmetic condition means absolutely nothing when a 9 or 10 underexposes all your film
and you have to send it away to have all that work done on it..
Click to expand...


True, but I've not been able to determine if it's equipment fault, or user fault just yet. The roll of FP4 that I developed yesterday that was shot with the same combo turned out very nice.

I haven't been able to replicate the problem I posted about, thus far. I have a very strong feeling that when I mounted the lens I failed to engage the meter coupling and thus severely underexposed the negatives in question.
 

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It's peripheral to the OP's issue, but I had a F2 that didn't get any voltage to the prism. In mine, the contacts of the mechanical switch that turns on the meter had a little bit of corrosion. It's under the bottom plate (it's actuated by a rod poking down from the wind lever area) and is easily accessed and cleaned.
 

Chan Tran

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I would agree to send the camera to Sover Wong. He takes a long time and expensive but if you simply want a camera that works I would just buy one that works. There are many F2 for reasonable prices that work perfectly. The high price is really related to the viewfinder.
 
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