The Pentax K Lens to Sony E-Mount Camera Lens Turbo Adapter Mark II from Mitakon allows Pentax K lenses to be mounted on Sony E-Mount APS-C format cameras, increasing the angle of view by 0.726x and the maximum aperture of the lens by 1 f-stop.

The four optical elements of the Lens Turbo adapter condense light from the Pentax K full frame lens and project it onto the camera's APS-C sensor allowing the sensor to capture all of the lens' transmitted light, negating the 1.5x crop factor and effectively producing full-frame coverage on non-full-frame sensors. A corresponding increase in the maximum aperture of 1 f-stop makes the lens more effective in low-light situations.

The Mark II version of the Lens Turbo features an improved design to produce sharper images. Its rectangular rear lens rests closer to the camera's sensor improving light transmission and an enhanced lens coating minimizes ghosting and flare. One extra-low dispersion (ED) lens element reduces aberrations for better delineated images. The adapter offers a sturdy metal construction and stainless steel mounts, it attaches to both camera and lens with little play and includes a front and rear protective cap. The Lens Turbo is a manual adapter offering no electronic communication between lens and camera.

The Lens Turbo adapters are compatible with APS-C sized sensors. Although they will physically fit the Sony full frame mirrorless cameras, the camera must be set to Crop Mode to fully support the speed booster's functions.

Pentax K Lens to Sony E Camera    Widens Angle of View by 0.726x    Increases Maximum Aperture 1 Stop    One Extra-Low Dispersion Element    Enhanced Lens Coating Reduces Flare    Rectangular Rear Lens Reduces Reflection    Manual Adapter

Allows Pentax K lens to be mounted on Sony E-Mount (NEX) camera

Increases the angle of view by 0.762

Increases maximum aperture by 1 stop

4 lens elements in 4 groups including 1 extra-low dispersion element

Optimized lens coating to reduce ghosting and flare and improve over-all image quality

Related Questions and Answers

Q: 1. Does this adapter allow m42 lenses to focus at infinity? Or is infinity focusing compromised turning the lenses to macro-like close focusing lenses?

A: The adapter does have infinity focus but it does not work with every lens. Lenses with protrusion beyond the mount by 3mm or more will not work.

Q: 2. Does this adapter have an aperture dial?

A: This one does not have it but I have seen another one that does by VILTROX. My preference was not to have the aperture ring and was interested in this one because all my lenses have it and two similar rings were confusing to me. I found the mounting mechanics on this adaptor to be really awkward and retuned it. I got the VILTROX and taped over the ring with black tape...

Q: 3. Will this work with the Sony A7R II? I know both the NEX cameras and Alpha cameras are Sony E-mount but it's a known issue with the dumb adapters that some only work on the Sony NEX cameras and not for Sony Alpha cameras.

A: It will work but that adapter is for APS-C sensor cameras and so it will produce a lot of vignette when used with the Sony A7R II.

Q: 4. Will this work for the Sony A7?

A: Yes, it works on Sony E-mount...

Q: 5. How do I focus using this adapter, do I focus with the lens or the adapter?

A: The lens would be focused in this case.

Q: 6. will this adapt ricoh lenses to sony a7 e cameras, if not which adaptor does this ?

A: While you can use the Mitakon Zhongyi Pentax K Lens to Sony E-Mount Camera Lens Turbo Adapter Mark II to mount Pentax K-mount lenses onto a Sony a7, you would need to shoot in APS-C /Crop sensor mode. You would need to use an adapter that is designed for full frame Sony E-mount cameras if you want to take advantage of the a7s full frame sensor. http://bhpho.to/2fVNIdj

Q: 7. Can I use this adapter with Nikon AF-S 70-300mm f/4.5-5.6G IF-ED Lens? Does it have aperture ring?

A: The Mitakon Zhongyi Nikon AI / AI-S Lens to Sony E-Mount Camera Lens Turbo Adapter Mark II does not have an aperture ring to control the aperture of the Nikon AF-S 70-300mm f/4.5-5.6G IF-ED lens. As it is designed for the older Nikon AI and AI-S lens, both which have aperture rings built into the lens, using the Nikon AF-S lens on this adapter will only allow you to shoot at the maximum aperture. If you need an adapter that allows you to set the aperture of the lens, you would need a Nikon G to Sony E-mount adapter, such as either the Metabones Nikon G Lens to Sony NEX Camera Lens Mount Adapter (Matte Black), B&H # MENFGEBM1, the FotodioX Adapter for Nikon G Lens to Sony NEX Mount Camera II, B&H # FONEX2ANG, or the Vello Nikon G Lens to Sony E-Mount Camera Adapter, B&H # VELANEXNG.

Q: 8. will this work on a Sony a7s in apsc mode?

A: Yes, this adapter will work with the A7s in APS-C crop mode.

Q: 9. Will infinity focus still work for Nikon F lenses?

A: My Nikon lenses focus to infinity with the Turbo Adapter.

Q: 10. Does Auto focus still work with this adapter?

A: Nope. There's no electronic connection between the camera and lens. It's just an adapter that converts your nikon f mount to Sony e-mount.