Pentax K-5 Operating Manual page 117

Using the p (Bulb) Mode
This setting is useful when shooting night scenes and fireworks which
require long exposures.
1
Set the mode dial to p.
2
Press the shutter release button.
The shutter remains open as long as the shutter release button is kept
pressed.
The following functions are not available in p mode.
- EV Compensation
- Exposure Bracketing
- Continuous Shooting
- Interval Shooting
- HDR Capture
B
AF.S
5.6
Bulb F
100
ISO
-5 4 3 2 1 1 2 3 4 +5
AWB
JPEG 16
M
115
4
11 11
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