The User's Review: Pentax Reverse Adapter K (49 mm, circa 1982) and How to Use

For magnification between 1.36 and 2.12, Pentax provided two reverse adapters (49 and 52 mm) for the prime lenses of 35 - 28 mm. 

To use the adapter, I found that it's easier to screw the adapter to the front of a lens first, then mount or dismount the assembly to a camera body. In the adapter instructions, Pentax does not mention how to mount.

To use a filter, it should be added between the lens and adapter. With a filter, the magnification will be slightly increased.

A filter size adapter can be used if you lens does not match the reverse adapter. 

Definitely, lenses with non-PK mount can be used on the reverse adapter as long as you can screw the lens onto the reverse adapter.

Below are five sample images without cropping, taken by a Pentax K-x and SMC Pentax-M 50mm 1.4 prime lens.

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