Ricoh PENTAX K-3 Mark III Faq page 52

Q: Can the S (screw) mount lenses be used with the K-3 Mark III?
A: Yes, you can use them combination with the Mount Adapter K.
*Under the default setting, the camera does not operate and display [F- -] in the
LCD panel. Perform the following settings before use.
1. Set the [Using Aperture Ring] to [ON] in the C6 Function Customization.
2. Set the [Length Input on Startup] to [ON] in the C6 Function Customization.
3. When pressing four-way key right, [MF Lens Focal Length] screen is
displayed. Enter the focal length of the attached lens and select [OK].
Q: Can the 645 format lenses be used with the K-3 Mark III?
A: Yes, you can use below lenses combination with the 645 Lens Adapter K.
*FA 645 lenses and HD D FA645 35mm F3.5 AL [IF].
*DA645 and D FA 645 lenses which do not have the aperture ring cannot be used
with the K-3 Mark III.
* Under the default setting, the camera does not operate and display [F- -] in the
LCD panel. Perform the following settings before use.
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