Nikon F4s will advance film without firing shutter...

<p>My Nikon F4s has recently developed the rather aggravating trait of triggering the film advance but not firing the shutter when I press the shutter button. The camera behaves 75% of the time, but sometimes I will be shooting and it will do this in the middle of an important scene and I will lose the moment I was capturing.</p>

<p>When it does this, it doesn't do it immediately, there's a delay. When the camera operates normally, I press the shutter button and the mirror lifts, shutter opens/closes, the mirror drops, and the film advance winds to the next frame. But when the camera decides not to work, I press the shutter button and there is a delay (half a second, roughly) during which time there is no mirror movement or shutter movement, then the film advances one frame, followed by the LED between the ISO wheel and the viewfinder flashing rapidly.</p>

<p>This problem will usually persist for several minutes, the camera will not resume normal function until I wait it out.</p>

<p>Does anybody have any ideas?</p>

<p>Could the mirror be getting stuck and since it doesn't move out of the way, the shutter doesn't fire ? I know some cameras get an issue where the foam gets sticky and has to be replaced. I don't know if this is an issue with the F4. I hope not, as I have one.I suspect that the film advances after waiting for a prescribed amount of time for the shutter. Once that time elapses, it figures some trick setting is being used and moves the film.</p>

<p> </p>

<p>It's a known issue with F4. Nikon repair facilities replace a small cogwheel when they service an F4. This wheel was made of plastic and gradually wears down so can't prevent the film advance motor from pulling the film though the camera. I have had both my F4 bodies serviced for this years ago.</p>

<p>I think what you are describing is what happens when the door is open. When open you will see a small black pin in the top indent on the left (that the door closses into) NOT the silver one on the right. With a pen try pushing the pin down then letting it pop up by sliding the pen off it. Not sure if it will work but its worth a try.</p>

<p>Thank you! It wasn't an issue with the foam, I believe it is the cogwheel that Bjorn is referring to. I will try and get my F4 serviced to solve the problem.</p>