Ricoh Lens A16 - Manual (Page 36)

[ADJ. Direct ISO Control]
When [ADJ. Direct ISO Control] is set to [On], you can push the ADJ. lever
sideways when shooting is possible to change the ISO setting. The default
setting is [Off].
Note --------------------------------------------------------------------------------------
• The ADJ. lever can be used to adjust sensitivity while the shutter button
is pressed halfway in program shift and aperture priority modes (in
program shift mode, sensitivity can be adjusted even after the shutter
button is released, as long as shutter speed and aperture are displayed).
Note that once sensitivity has been adjusted in this manner, [Auto] and
[Auto-Hi] can not be re-selected.
• In manual exposure mode, you cannot use the ADJ. lever to change the
ISO setting.