F2 shutter issue

[User_4754088]

<p>My beloved F2 has an intermittent shutter issue that's driving me nuts. Wonder if anyone else has dealt with this. My best guess is that intermittently the first shutter curtain is hanging up for a split second at just about the end of it's travel (as illustrated by the dark band on the right edge of the photo below). With the back of the camera open I can't seem to make this happen, but from studying the images, that looks like it might be the issue.<br>

<img src="http://www.timcarrollphotography.com/Forums/F2Shutter.jpg" alt="" /><br>

Anyone have any thoughts on this? The camera was serviced less than a year ago and this will happen on two or three frames, every second or third roll of 36.<br>

Thanks for any and all input.<br>

Best,<br />-Tim</p>

[craig_shearman1]

<p>Google Sover Wong and ask his opinion, then send it to him if it needs work. He is the worldwide F2 repair guru.</p>

[Andrew Garrard]

<p>Completely not my area of expertise (I don't even know whether the shutter travels left to right or right to left on an F2...), but are you able to reproduce this at the maximum shutter speed? Just thinking that the minimum gap between the two curtains might tell you more about what might be going on. That said, I guess it can't be mechanical vignetting or you'd see it on every frame.</p>

<p>Good luck. I believe you that the shutter might be glitching.</p>

[scott_murphy5]

<p>The F2's, mine like yours, are getting pretty long in the tooth. It might be in need of some professional service.</p>

<p>For Andrew, the shutter travels left to right. </p>

[User_4754088]

<p>Communicated with Sover, and the shop that completely overhauled the camera (including replacing the shutter mechanism) last November. Everyone is in agreement that it's shutter bounce so I'll need to send the camera in and have it fixed.</p>

<p>Thanks for everyone's input.</p>

[Andrew Garrard]

<p>Good luck, Tim. Glad you have a route to a solution.</p>

<p>Scott: So that's the <em>start</em> of the exposure that's shaded? Or do you mean left-to-right as seen from the (inverted) image's perspective? Not that it matters if the shutter is being overhauled anyway, but I'm here to learn!</p>

[User_4754088]

<p>What you see in the image above is the first shutter curtain coming across, hitting the brake, and bouncing back slightly (causing under exposure on the right side of the image) before the second shutter curtain comes all the way across and closes the light path. That corresponds to the direction of shutter travel on the Nikon F2 camera. Other cameras may be different, depending on their shutters and their direction of travel.</p>

[Gus Lazzari]

<blockquote>

<p>"Everyone is in agreement that it's shutter bounce" <em><strong>Tim C.</strong></em></p>

</blockquote>

<p>Not everyone, because<strong> I don't agree.</strong><br /> If your image is what we're diagnosing, then a bounce would add exposure. This would show up as a lighter "bar" than the rest of image. A darker bar like yours, means that the first curtain is hesitating before exiting the image frame as the 2nd curtain "pushes" it closed.<br /> A true "bounce" would finish it's travel, then with a lack of deceleration, allows the 2nd curtain to bounce back to <strong>re-expose the film</strong> as far as it bounced...<br /> <br /> Many things in the shutter or brake mechanism can cause this friction your camera is experiencing; lube failure, obstruction, drag from wear, or maladjustment.</p>

[Andrew Garrard]

<p>With the proviso that I'm trying to understand this myself... Gus, I think Tim's argument is that the first curtain runs to the edge of the frame (exposing the film), then bounces back, blocking it again. The second curtain runs evenly. Your discussion of adding to the exposure would be the second shutter bouncing, not the first one. I've no idea whether it's possible for both shutters to bounce, and whether this is more likely than some kind of hesitation.</p>

<p>I'd be pointing my V1 at this and capturing a 1200fps video in the hope of seeing the problem, but it might be too subtle to show up...</p>

<p>(To answer my earlier question, I guess the shutter moves right-to-left across the back of the camera, which means that a problem at the end of the exposure will be on the right of the inverted image.)</p>

 

[Gus Lazzari]

<blockquote>

<p>"first curtain runs to the edge of the frame (exposing the film), then bounces back, blocking it again." <em><strong>Andrew G.</strong></em></p>

</blockquote>

<p>That's quite a distance to bounce back !<br>

If a "brake" was <strong>applied to such a max</strong> that the 1st curtain was close to the edge of the film opening, it couldn't bounce (The brake is on max !).</p>

<p> <br>

First curtains in fact have very little braking action because the stop is <strong>deep inside</strong> the curtain travel. <br>

It's the second curtains that require major deceleration, otherwise they'd "slam" into the 1st curtain rib. <br>

Instead, it's cushioned at another point inside the shutter mechanism.</p>

[User_4754088]

<p>Hi everyone. First, I want to thank everyone for their input, it has all been really helpful. This is an issue that doesn't follow logical thinking as I have heard from a number of different technicians I've talked to about what it could be. </p>

<p>Andrew made a suggestion that I didn't know was possible. My crude shutter tester uses my Nikon 1 V2 camera. I was not aware that this camera can shoot 1200 fps. Once I figured out how to do that, I was able to make a video, and sure enough, the first curtain is coming completely across, disappearing out of frame, and then bouncing back into the frame for a split second before the second curtain comes across.</p>

<p>The V2 will only capture a small area at that frame rate, so here is the slice I took of the shutter mechanism for the video.<br>

<img src="http://www.timcarrollphotography.com/Forums/Slice.jpg" alt="" /></p>

<p>And here is a Quicktime movie of the shutter at 1/250th of a second (the speed where the issue is the worst). If you watch the video carefully you can see the first shutter curtain finishing it's travel and then "bouncing" back into the frame.</p>

<p>http://www.timcarrollphotography.com/Forums/Bounce.mov</p>

<p>Here are a few individual frames from the video (the orange background was the light source showing through the open shutter):<br>

First curtain finishing its travel:<br>

<img src="http://www.timcarrollphotography.com/Forums/Bounce1.jpg" alt="" /></p>

<p>First curtain starting to bounce back into the frame:<br>

<img src="http://www.timcarrollphotography.com/Forums/Bounce2.jpg" alt="" /></p>

<p>First curtain stops into the frame as second curtain is finishing its travel:<br>

<img src="http://www.timcarrollphotography.com/Forums/Bounce3.jpg" alt="" /></p>

<p>And finally second curtain finishing its travel (and maybe pushing first curtain back out of the frame);<br>

<img src="http://www.timcarrollphotography.com/Forums/Bounce4.jpg" alt="" /></p>

<p>Maybe I'm weird, but I do find this fascinating, although frustrating.</p>

<p>Thanks again for everyone's input.</p>

<p>Best,<br>

-Tim</p>

[scott_murphy5]

<p>Andrew, with the camera back open, when you trip the shutter the curtains move from left to right. Sorry about the confusion</p>

[Andrew Garrard]

<p>Tim: Glad to have been helpful, and thank you for sharing! Interesting to see, especially for someone who only owns cameras with vertical shutters. The high speed video modes are the main reasons I have a V1, although that may change if I ever get an FT1.<br />

<br />

Scott: Thank you for educating me. Although now I'm really confused. If the image is inverted inside the camera (unless lenses have started working differently from how I think) and the problem is at the end of the shutter travel, shouldn't that mean the curtain moves right-to-left (as seen from behind the camera)? The left side of the scene - without a problem - should be nearest the camera grip, if that disambiguates at all. I may just be too tired to handle trivial geometric transformations...</p>

[Gus Lazzari]

<blockquote>

<p>"First curtain finishing its travel" <em><strong>Tim C.</strong></em></p>

</blockquote>

<p>It's not <strong>finishing</strong> it's travel, it's striking some sort of <strong>resistance/obstruction</strong> on the non-freewheeling mechanism side (left), and then the titanium foil is buckling the rib back from the freewheeling no mechanism mainspring side (right).<br /> "Finishing" would occur deep into "stage right" (looking from the lens mount) halted by (at left) minor brake deceleration mechanism. <br /> <br /> A classic symptom "bounce", is what I described, as a lighter line of exposure.<br>

Once again, "<em>Many things in the shutter or brake mechanism can cause this friction your camera is experiencing; lube failure, obstruction, drag from wear, or maladjustment</em>."</p>

[User_4754088]

<p>Well whatever it is, the camera is back at the shop that was supposed to fix it last time. The shop that supposedly put in a new shutter mechanism (whatever that means). If it comes back and is still screwed up, I'm binning that body and finding another.</p>