Been playing around with my K10D using a M42 Auto Chinon 135mm, F2.8.
These are the two best pictures I've taken so far.
I've done some light post processing in order to enhance the colours slightly and remove the worst noise.

Both were taken at ISO400 and an exposure time of 1/125s. I think that the aperture was set to F5.8, but I honestly can't remember it. Kind of the biggest problem with M42 lenses, remembering the aperture size :-)

Let me know what you think about the images.

[fevbusch]

Hi, Paul. I like the butterfly shot. Nice composition and nice color from that Chinon lens. I would do some post processing to cut out the broken twig in the foreground which distracts from the nice peaceful image. Have fun, Freddy

[PaulF]

Good suggestion to get rid of the twig, thanks. Attached is the cropped version. I really like it.

The lens really surprised me positively. Bought it rather cheaply together with 5 other M42 lenses. Still have to learn to use them to their full extend :-)