Pentax R-2501NS Instruction Manual page 53

[Adjustments]
When the bubble of the circular vial comes off from the centre according to check procedure
②, it is necessary to adjust.
Turn the bubble adjustment screws with the reticle adjustment pin and put the bubble in the
centre of the circle.
[Only the detaching type model]
Turn the bubble adjustment screws with the reticle adjustment pin and put the bubble in the
centre of the circle.
• Tighten the screws equally after the above adjustment.
Circular vial adj. screw
Circular vial
Circular vial adj. screw
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