Canon 1D X - Manual (Page 178)

178
When bulb shooting is set, the shutter stays open as long as you hold
down the shutter button completely, and closes when you let go of the
shutter button. Use bulb exposures for night scenes, fireworks, the
heavens, and other subjects requiring long exposures.
1
Set the shooting mode to <buLb>.
Press the <W> button and turn
the <6> or <5> dial to select
<buLb>.
2
Set the desired aperture.
While looking at the top LCD panel,
turn the <6> or <5> dial.
3
Take the picture.
While you hold down the shutter
button, the exposure will continue.
X The elapsed exposure time will be
displayed on the top LCD panel.
1: min., 2: sec., 3: hour
Bulb Exposures
(1) (3) (2)
Long exposures produce more noise than usual.
When [z2: Long exp. noise reduction] is set to [Auto] or [Enable],
noise generated by the long exposure can be reduced (p.148).
For bulb exposures, using a tripod and Remote Switch RS-80N3 (sold
separately) or Timer Remote Controller TC-80N3 (sold separately) is
recommended (p.179).
COP
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