Nikon F3 DOF button hardness?

<p>Hello Nikon F3 users,</p>

<p>Sorry for interruption, but I would like to know how does it feel when you press DOF preview button on it? Is it smooth motion or rough/hard one?</p>

<p>I'm asking because I recently bought used F3 which looks like brand new, and on other Nikon FM3a same button is quite smooth, but on this F3 I can press it all the way without a problem but it feels hard and like I'm pressing it in steps.</p>

<p>So, is it something wrong with it, without lube or what? Or is it normal because camera is like unused so it will work out more smoother trough time later?</p>

<p>Thanks :)</p>

<p>Mine is firm but smooth.</p>

Ditto - firm but smooth. Allows me to see the darkening gradually. It shouldn't feel like "steps".

<p>Mine works smoothly and firmly, but also has what feels like a single step, about a third of the way down. it does not seem to affect the actual movement of the aperture lever, but it does feel as if an additional resistance has been introduced.</p>

<p>Mine is smooth. I can see the aperture blades move when I lightly press the button, but do need to push it a little bit hard to get it all the way down. I guess yours is normal.</p>

The F3 button is stiffly sprung with no leverage.

There's some stacking feeling toward the end of

the travel, which is normal with any simple

coiled compression spring. But it's reasonably

smooth.

 

The FM2N spring is about the same, but the

leverage makes it feel smoother and lighter.

 

Nikon DOF previews are the stiffest of any SLR

I've owned. Very complex system of moving parts.

Olympus OM lenses are the easiest - it's right on

the lens.

<p>Mine is firm and smooth even after twenty some years.</p>

<p>-O</p>

<p>I see the point, the preview lever spring does seem a little unaturally strong, but not disfunctional, or not getting progressively worse. Pressing the preview button, and locking up the mirror does require some intent. I think it qualifies as a mechanism that needs oil from time to time, like maybe 3 times a year.</p>

<p>Lex explanation fit my camera at 100% :)<br>

My guess is that Vlad`s camera is fine. The F3 is a workhorse, so it works... like a horse?</p>

<p>Thanks guys. :)</p>

<p>Just wonder, how often do you give to maintenance service (clean, oil, etc., when not broken) your F3? </p>

<p>I bought my F3 new in 1986. It still works fine & the only service has been a replacement of the foam pad the mirror bounces against. That was about twelve years ago.</p>

<p>Mine is also from the eighties. I sent it two times for meter adjustment, nothing else.</p>

<p>Just one more question, if I may ask. :D</p>

<p>When you press DOF button all the way in, aperture level goes all the way down. But, when you use camera to do so, while shooting (say 4 secs. time so you can check it), does aperture level go all the way down exactly same in millimeter as pushing DOF button all the way, or does it stay say two millimeters up from lowest position? Check it.</p>

<p>Because, mine stays around 2mm above final position.</p>

<p>I'm the second owner of mine. I'm sure the first guy did nothing. He hardly took pictures with it. I've replaced light seals, the mirror bumper and batteries. That's it. Built like a Tank and works like a Toyota.</p>

<p>I have not done the test Vlad suggests because my F3 and F4 both have film in them. But in both, the lens finishes stopping down long before the button bottoms out. In order to avoid accidentally pushing so hard on the mechanism in the lens that it bends or breaks, the DOF button is provided with a spring that allows it to continue traveling after the lens has stopped. It would be a great strain on the mechanism, and would feel strange too, I think, if the DOF preview simply stopped cold when the lens hits its set aperture. This also accounts for part of the "stepped" sensation. The button becomes harder to push, but still can be pushed, when the lens has stopped but the spring is being compressed. I would expect that the phenomenon Vlad sees here would be true unless you have a lens whose minimum aperture is the smallest of all existing or contemplated Nikon lenses, closed down all the way. </p>

Lubrication probably wouldn't help and any

modifications should be done by an experienced

repair tech. Oiling stuff willy nilly will make a mess inside the camera.

 

The feel could be improved by

polishing mating surfaces. The inside of the F3

DOF button probably has some ridges or milling

marks. A variable compression spring would help.

 

These are the sorts of modifications custom

gunsmiths offer but camera techs seldom do.

<p>The DOF button is coupled with the lever that raises the Mirror. If this lever is not fully back in place, it can block the DOF button. Check the mirror lever position.</p>

<p>Mine is heavy and smooth. It's always that way not heavier as it ages.</p>

<p>I clearly have it a bit backwards above, as the camera's aperture lever drops out of the way of the len's aperture lever, so it allows the aperture to close under its own power rather than pushing it. There still is a change in resistance when the aperture hits its limit, after which the lever continues on its own.</p>

<p>On a Nikon F, using Vlad's test, the DOF button does go all the way to its limit when the shutter is open. Taking the lens off my F3 and just operating the lever I find the linkage there is also quite direct, and works smoothly. Any irregularity would appear to be in the lens. </p>

<p>I still wouldn't worry about it if it's working right, though. </p>

<p>Actually I agree with Lex, its not a good policy to be lubricating camera parts without having a plan. Although where the aperture coupling lever in the lens is in contact with the aperture activation lever in the body, that contact surface should be checked for roughness, and if need be lapped in, and then lubed with the smallest dab of lithium grease.</p>

<p>Both my tests were done without lens.</p>

<p>So, <a href="/photodb/user?user_id=696354">Les Sarile</a> said that there is difference between DOF button and shutter position of aperture level.<br /> <br /> <a href="/photodb/user?user_id=869561">Matthew Currie</a> said "On a Nikon F, using Vlad's test, the DOF button does go all the way to its limit when the shutter is open. " and I didn't understand that well. F or F3? DOF button and shutter position are same in mm on yours?</p>

<p>Anybody else took the last test with aperture level positions (without lens please)?</p>

<p>Sorry for me being peculiar about this, but I would like to know. And sorry if my English is not that good. :)</p>

<p>As a side note, a defect DOF button might cause the shutter to fire. When a friend tested his FM2N throroughly and pressed the DOF button quickly about 30 times, the shutter actually fired!</p>

<p>He took it back and got it serviced under warranty and it has since not showed the same behaviour. They were quite surprised when he described the fault and how he discovered it but took it in imediately.</p>

<p>Perhaps the F3 has similiar DOF mechanics (I know its shutter speeds are electronically controlled), if so it might be an indication of an upcoming need for service.</p>