Remote cord shutter time

Bulldog630

I set my camera on aperture priority and use the remote cord. I have a 5 second shutter speed. I press the shutter button and hold it for 5 seconds then let it go. The shutter always stays open for 10 second. Why is this? Am I doing something wrong?

bruto

If you're on aperture priority, the shutter speed will be set by the camera's meter and not by the time you press the button. If the meter says it should be 10 seconds, then it will stay open for 10 whether you hold the button down or simply give it a quick press.

If your exposures are correct, then there's no problem.

You can't set a particular shutter speed in A mode.

Bulldog630

Can you shoot under 30 seconds in bulb mode?

bruto

You can shoot under 30 seconds in bulb mode, but to your own count, which may not be as accurate.

I'm not sure how the wired remote works for the D3100. The D3200, in bulb mode, operates differently when in remote than when using the camera shutter button. The regular button stays open as long as you press the button. The remote opens the shutter on the first push, and closes it on the second. This makes it harder to time a short exposure, but much easier to shoot a long one without vibration.

That should be easy to find out. Just operate it in remote bulb mode, and see if it stays open until the second push, or stays open only as long as you hold the button down.

Bulldog630

Thanks Bruto I'll try that.

seanhainesd3100

How long can you go in remote bulb mode? I've heard about overheating. Mine never did, and I did it for 15 minutes.

bruto

I have not heard of any danger from sensor overheating. I think many SLR's these days have some kind of safety shutdown for extreme cases anyway. The sensor does heat up but as far as I know the only result is more digital noise as more hot pixels develop and send spurious information. If you're not bothered by noise then no problem. If you have noise issues it might help to take multiple shorter exposures and stack them but of course that requires that you have the software capability to stack, and that no objects are so faint that they don't show at least a little in the shorter exposures.

Long Exposure Noise Reduction can help some but because it basically duplicates an exposure with the shutter closed, it doubles the time taken by each exposure, which could obviously be a pain in the neck for very long shots. A 15 minute exposure would take a half an hour to complete.