Sometime this last year I acquired this adapter to allow a Minolta manual focus bayonet lens to be mounted on a Pentax K type bayonet mount camera body. It incorporates an optical group in the middle to adjust for differences in lens to mage plane distances.

Yesterday I finally had the opportunity to test it out to see how well it works. I took my very fast Minolta MD f:1.2 / 50mm lens and mounted it with the adapter to a Pentax *ist D digital body.

It was a beautiful early Fall day. Test began in our front yard. From there I took it to Minnie Ha Ha Park on the Meramec River in Sunset Hills.

Camera was set to Aperture Priority mode, and auto metering set the shutter speed to match with the actual aperture of the lens. I was able to manually open the aperture wide for easier focusing, then stop down while I watched the camera select shutter speeds.
Lens performed well enough when stopped down a bit. But when I exposed with aperture wide open, crazy things happened. See images number 5540, 5564, 5600, and 5620.
Also, something in the design of the adapter is not quite right, and distance scale on the lens did not match actual focused distance. Fortunately the lens focused past the infinity mark, rather than short of it, so I was able to work with that okay.

I do not know what the reputation for this lens model was. But for me it seemed to deliver good images, when stopped down. Wide open at f:1.2, however, it did not do so well, with lots of flare and distortion.

Everything was shot hand held and available light. Readouts I saw in the finder showed shutter speeds from maybe as slow as 1/8 second to a top speed of 1/4000 when lens aperture was wide open at f:1.2 in full sun.

Please click on thumbnails to see enlarged.
All images are ©2018 E.J.Kowalski.
Thanks! Ed