+5.24 mm
Space for the adapter
50.70 mm
Tamron Adaptall flange
45.46 mm
Pentax K flange
Verdict: Yes — a simple 5.2 mm adapter keeps infinity focus.
What to expect#
Aperture control: these are mechanical lenses with aperture rings — set the aperture on the lens and shoot in aperture-priority or manual.
Focus: use focus peaking and magnification in the viewfinder. Exposure metering works normally because the camera meters through the lens at working aperture.
Tamron Adaptall lenses you could adapt#
Pentax K cameras#
- Ricoh Pentax KF 2022
- Ricoh Pentax K-3 Mark III 2021
- Pentax K-1 II 2018
- Ricoh Pentax KP 2017
- Ricoh Pentax K-1 2016
- Ricoh Pentax K-70 2016
- Ricoh Pentax K-3 II 2015
- Pentax K-3 2013
- Pentax K-50 2013
- Pentax K-01 2012
- Pentax K-5 II 2012
- Pentax K-30 2012
- Pentax K-5 IIs 2012
- Pentax K-5 2010
- Pentax K-r 2010
- Pentax K-x 2010
- Pentax K200D 2008
- Pentax K20D 2008
Other systems for Tamron Adaptall lenses#
Frequently asked questions#
Will Tamron Adaptall lenses autofocus on Pentax K?
No — adapted lenses are manual focus on this combination.
Does a Tamron Adaptall to Pentax K adapter affect image quality?
A glass-free adapter is just a precisely machined spacer, so image quality is unchanged when it is built to the right thickness. Cheap adapters can be slightly too thin or thick, which shifts the infinity mark.
Last updated October 03, 2026 · How we calculate · Sources