That's the one, many thanks!

The pentax has a focal plane shutter, in which two curtains allow a slit of light to progressively travel across the CCD. The faster the shutter speed, the narrower the slit. Thus, the propellor is in a different place as the slit moves, causing the effect we see. There is a famous old photo of a racing car where the wheel becomes oval for the same reason. Focal plane shutter distortion.

The Sony I presume is a compact or bridge camera with an electronic shutter that combines a shutter that is opening to show all the frame at the same time, some sort of leaf shutter, combined with a "freeze frame" where the CCD itself is part of the shutter process. The result is no distortion.

Personally, at that price it doesn't attract me, even though I'm a totally hopeless for buying lenses I don't need. A 60mm-equivalent lens gives me nothing my 50mm f1.4 won't.

If someone wanted one, presumably for its compact, high quality aspects, then it's a case os supply and demand. It's worth what the buyer can be persuaded to pay.

If I were putting such a lens on eBay I would give the description and photos my best shot, start it at £20 and hope for the best. This usually works out just fine, but I take no responsibility whatsoever if you try it and it doesn't.....

Good luck!

Thanks for the link - very interesting too.

The 16-45mm sits on my K10D most of the time. A brilliant lens.

Prieni, sorry I missed your comment. Have a great holiday.

I therefore invite karma mechanic to set and judge the new competition.

As for the posting of titles, I'm reluctant to add any more rules to such a rule-light competition.

As long as everyone is reasonable with their descriptions I'll hold that thought and see how it works out, for a while at least.

Another superb set of images, congtas everyone.

Prieni, we await #18 with keen anticipation.....

If a lens is used that does not have the ability to "talk" to the camera then the camera will prompt us to enter the focal length so that the correct amount of SR can be used.

All lenses with electronic contacts (A series onwards) will communicate properly without any need for manual SR setting.

If screw thread, K series, M series, 645 or 67 lenses are used (with adapters where appropriate) then the electronic contact is not there or lost and manual SR setting is prompted.

Very impressive shot, well done.

No problem with you being a GX10 user - welcome.

Astronomical photography has been done with digital cameras for some time. Maybe someone here has the expertise.