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Photography Question 
Jo-Anne Walsh

What Does Bulb Mode Means?

I am a beginner photographer and I have a Canon Rebel 2000 and for the first time I heard the term "bulb" mode. What does it mean, and what do I do? Also what is the purpose? Thanks!!

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7/17/2004 10:03:30 PM

Damian P. Gadal
BetterPhoto Member Since: 4/22/2002
  Bulb mode will keep the shutter open as long as you push down the shutter button. So, you are in complete control of the exposure ... You can also use it when cleaning a CCD and you want to keep the shutter open.

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7/17/2004 10:42:49 PM

Steven Chaitoff
BetterPhoto Member Since: 6/22/2004
  Hey Jo-Anne: Typically you'll just want to use a timed shutter, because most subjects don't require shutters more than a second or so, but the bulb has some interesting and creative uses. For example, if you're out at night and with little light, you can leave the shutter open for a long time and capture the motion of the stars around the north star. I even know one guy who left his shutter open for 9 or 10 hours, all night outside in the pitch black, and captured a scene entirely from the light reflected off the moon!

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7/18/2004 8:51:38 AM

John A. Lind
BetterPhoto Member Since: 9/27/2001
  Historical Notes: At one time, many moons ago, most of the top-end cameras had a "T" and a "B" shutter speed position. The "B" as already described means "Bulb" and shutter is open as long a shutter release is held down. The "T" means "Timed" and was intended for long timed exposures Pressing the shutter release opens the shutter; either pressing it again, or turning the shutter speed dial, or moving a lever is required to close it. I have an old camera with both "B" and "T" on the shutter speed dial.

The "Bulb" shutter speed position name comes from the early days of flashbulbs, which were invented in 1929. Prior to flashbulbs, flash powder was used. One would open the shutter, light off the flash powder in an elevated trough and then close the shutter again. There was no shutter synchronization with flash.

Cameras made shortly after flashbulbs were invented likewise had no flash synchronization to fire the flashbulb while the shutter was open ... requiring the same method of opening shutter, manually firing the flashbulb, and then closing the shutter again ... hence the "Bulb" name it was given.

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7/19/2004 11:53:48 PM

Scott Pedersen   When you do try out your B setting, use a cable release. Don't just press the shutter with your finger and hold it down. A locking cable type lets you leave the shutter open for extended periods.

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7/20/2004 3:50:02 AM

Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
  A Canon Rebel may not have a way to attach a cable release.

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7/20/2004 10:27:05 AM

BetterPhoto Member Since: 5/28/2002
  Luckily, the Canon Rebel 2000 has a remote control terminal on the side that can be attached by the remote switch RS60-E3. So do the Rebel Ti and GII.

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7/20/2004 11:44:39 AM

Steven Chaitoff
BetterPhoto Member Since: 6/22/2004
  You can attach a cable release, but not a generic one. Canon uses its own proprietary system, so you have to buy theirs. It'll cost more, of course, but there are a bunch on eBay! The name of it is the Canon RS-60E3 Remote Switch Cable Release.

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7/20/2004 11:49:44 AM

Norman Ewan   Painting with light in simple terms: Set you camera to manual mode and focus on your subject. Set the bulb mode then in total darkness press the shutter button to open the shutter and shine a touch on the subject moving the light around. You can get some great effects.

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7/20/2004 12:43:30 PM

Bill Wassmann   Bulb is a very old term and comes about not because of flash powder but because many of the early shutters were operated by air. A flexible rubber tube attached to the shutter and at the other end was a rubber bulb. When you squeezed the bulb the air compressed and activated the shutter. The word has persisted for many years. When shutters became mechanical the T for Time was added and required two actions: one to open the shutter, one to close it.

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7/22/2004 12:50:41 PM

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