Pentax 67 Operating Manual page 26

SHUTTER DIAL/BUTTON
1
To prevent camera shake, please press the
shutter button gently, while holding the
camera securely. Please practice releasing the
shutter to capture the moment as you desire
without causing camera shake.
2
When the shutter lock lever is aligned to the
red dot, the shutter is locked. This is helpful to
prevent accidental shooting.
22