The pictures tell the whole story. Thanks to Darren M of DPReview for sharing this:

http://www.fishki.net/comment.php?id=26844%22

Nols

noli p,

here is the less spurious link:

http://www.ralfbrunner.com/ralfbrunner_website/pages/aids3.html

it also appeared in TOP before (http://theonlinephotographer.com/the_online_photographer/blog_index.html

CP

Thanks Chelo. something must be off with the webpage (or my browser) - the pics don't appear in the first link.

Nols