bought this product because I already had other K&f concept adapters for Pentax K to M43 that I was happy with. So I bought the Sony E adapter for my son. This now allows him to use his Pentax K lenses on his Sony A7 (operation verified with DA15, FA31 and FA77). I chose the model with a ring that allows you to adjust the aperture of your Pentax lenses without an aperture ring (e.g. DA15, DA35, DA55-300) by acting on the clutch lever on the support, and of course with the lenses that are equipped with an aperture ring (FA31, FA77 and F135, M50 and M28).

bought it to use with the many Pentax K-mount lenses (of various generations) that I use on the Pentax KP, including the Sony A7r 2 that I recently added to my kit. The adapter is well made and is made of very solid metal for the structure, for the connector and for the bayonet. The polished metal notched ring seen in the center allows the membrane to be closed between the maximum and minimum of 11 positions without reference. Basically, you can close the aperture of any lens, but you don't know exactly what value it's set to (other than, of course, the two extremes that correspond to the maximum and minimum of the lens mounted). This obviously applies to the most modern optics without their own aperture ring. The rotation of this ring, which basically wants to simulate the membrane ring, is quite fluid and has small shots to facilitate positioning as much as possible. I've used it with various Pentax APS-C lenses, from the old 50M 1.4 to the Sigma 18-35 f/1.8 Art and 17-70 f/2.8-4 C. All work flawlessly, always within the limit , which is imposed on the most modern models of an approximate selection of the membrane. Obviously there are no electrical contacts, so there's no exif data on the optics and the focus is only manual (but the A7R2 is excellent in that regard). It is precisely the need to focus manually and without an electronic connection that prevents the use of some modern lenses, that is, those in which the focus ring does not work mechanically, but through the camera module. For example, the DA 18-50 WR RE, a very versatile and lightweight lens that I personally hold in high esteem, is sadly useless as there is no way to focus. Apart from this limit, which the adapter obviously cannot fix, the product is very valid and allows you to take excellent quality images of optics designed for another brand. In particular, the Sigma Art 18-35 still offers spectacular photos, even if you use the APS-C crop mode (however, with the 42Mpixels of the A7R2 sensor, you can take 18Mpixel photos, which are still valid).

Perfect for using my old lens on my new Pentax!

The adapter does exactly what it is supposed to, namely to use my Pentax lenses on my Sony. The adapter's own aperture ring is particularly helpful because the lenses do not have their own.

it's good, it works, i have the pentax k version and now i have my vintage lenses on my a7ii

It solved the problem of being able to use a Sigma 18-200 lens with a Pentax mount without an aperture ring on a Sony A6500.

With Nikon Z and Pentax optics also with 42x1 screw optics.

When you open the incoming package, you will find that the packaging is very high quality. The brand is very careful in presenting their products and the materials are of high quality. The filter holder and adapter ring are metal and the filter holder has a spongy area whose function is to seal with the filter without letting light through. Once the filter holder is attached, it is easy to move. crtsal 100x100 quality is very good, with highly polished edges. The filter holder has two slots for square filters, but the advantage is that the ring screwed on the lens can be screwed with another round filter, for example a polarizing filter. I think the picture is very good. As with the brand's round filter, the sharpness is not lost, the color cast did not catch my eye, anything that can be edited during development is appreciated. The ND1000 filter included in the kit enables long exposures in strong light. The sample photos are photos taken on a cloudy afternoon with and without a filter. Those with filters were made with an exposure time of 20 seconds.