Shooting causes image jump

katew434

Hi, I suspect this a problem with my shutter, but wanted to see if any other ideas came up, or tips on how to fix it!

Not long ago my camera started doing this, then the mirror got permanently stuck open and I had to give it a nudge with a cotton bud to get it back in position.

Now the problems have started again. Every time I take a photo I line up the image, then when I press the shutter the image 'jumps' to the right. The resulting image taken then cuts off the left side of my composition.

I have had to resort to anticipating this and lining the shot up left of where I want it to be, to mitigate against the shift.

Any suggestions much appreciated, camera repair shops will charge more than the camera is worth!

Thanks, Kate

bruto

My first inclination would be to wonder if the mirror or the viewfinder screen has become dislodged or crooked. If it jammed once, it could be that it's not operating squarely, and as a result what you see in the viewfinder will not match what hits the sensor.

the shutter and the mirror both operate up and down, so usually a shutter malfunction will show up as a horizontal shadow.

To check first things first, switch to Live View and take a picture then. Since Live View is mirrorless and viewfinder-less, what you see in the preview should be exactly what you see on the image. I am guessing it will be, and that what you have is a cockeyed mirror.

Some of these cameras do have an issue from time to time with mirror jamming, but it is usually being stuck closed rather than open. It's got a pretty delicate pivot, so many things are possible.

Take off the lens and see if you can detect any misalignment of the mirror when it's down. It won't take much to mess up the view. With the mirror down, the gap at the bottom should be even. The viewfinder screen above should also be visibly straight, and not down at any corner. You'll barely see the little hinge pins at the top, with a return spring on the left hand one (as you face it). If you put the camera on manual mode and a long shutter speed, you should see the mirror go up, and once again it should be straight and even as it comes up against the foam bumper. With the mirror up you can see the hinge pins a little better. Everything should be straight.

I am guessing that you did not actually damage anything when you unjammed it, but that the jam itself was caused by some damage or wear on the mirror hinge.

As for repair, that is a big nasty issue, as the D3100 is not terribly valuable, and a used replacement can probably be gotten for less than the cost of the repair, unless you can figure out how to do it yourself or have it done by a local shop.

If you're really liking this camera and find it adequate to your needs, but can't see your way to a repair, consider upgrading to a D3200 or 3300. Especially on the 3300, you'll get higher pixel count, two IR sensors for remote, better ISO performance, and compatibility with E and P lenses, some of which are very nice. The D3200 makes good images, but it's a little noisy at high ISO. It can use E lenses but not P. The D3400 and 3500 are also good, but actually drop a couple of features, including the sensor shaker (for cleaning) and the double IR sensors, and also will not meter with older AF lenses. The D3100,3200 and 3300, though they won't focus a motorless AF lens, meter correctly.