What good is "bulb" feature?

[ken1953]

Hi all,
I was reading another thread this morning about taking a long exposure and noise problems. So far, everything I've read basically says that anything over a minute, with most digital cameras, is useless. For example, the lowest ISO on my Pentax is 200. Even with 30 sec night shots, I was getting so much noise that the shots were useless. I don't have Noise Ninja, but from what I've read, even that has it's limitations. I would think my Nikon Coolpix could do much better since it has ISO 50 and with the few night shots I tried with it, I did manage to get a few that were ok but still very noisy. So, I ask, what good is having the "bulb" setting on most digital cameras?
This is just a thought for discussion and ideas to help me better understand long exposure as it deals with digital cameras. I understand that film, for now, is the better way to go with long exposures...but...I, like many others nowadays, am a digital user.
I'll be very interested in seeing what everyone has to say.
Thanks,
Ken

[another view]

Probably useless or close to it, I'd think. I know I've never used it on my 5000 but have used it on film cameras. Your Coolpix has ISO50, but the sensor is so much smaller that the end result is probably close to a larger DSLR sensor at 200. It isn't just the ISO setting (and a lot of cameras are minimum ISO200) it depends on the camera.

The original use for a "bulb" setting was with flash bulbs from a long time ago. Maybe it would be handy in a studio if it was completely dark and you timed a strobe to fire at the moment something happened so you'd get your exposure without worrying about syncing to the camera, but on these cameras you'd really only have a couple seconds (if that) to do it before noise would be a problem. Shots of balloons breaking, etc are done that way...

[drg]

Bulb setting can also be used to open the shutter to 'wait' for something like an externally triggered strobe or flash.

If you wanted to experiment with motion capture of a ball bouncing, you could set the camera up on a tripod in a dark environment facing a dark backdrop and open the shutter and drop a ball in front of the camera while triggering a strobe or flash. Then close the shutter. Where you might not have complete control of synchronization of flash or are unsure of low light or an event it can be real helpful.

Say you wanted to capture the streaks of light on a highway or street and wished to have a light from a vehicle extend only a certain distance in the frame, you could just 'turn on' the exposure when you desired and then turn it off. In these cases a Polarizer of Neutral Density Filter can help to lenthen exposure time and many times cut the sensor bloom effect. If you have night shot (usually takes a dark frame and subtracts the hot pixels) this might be a good combination for those longer exposures.

This is not quite as simple as it sounds here, but these are some things that can be done with a bulb setting.

[Chunk]

Sorry Ken, you're too late. Bulbs should have been planted last fall. You'll notice that many that were are now popping up with som beautiful blooms.

Sorry... couldn't resist.