BirdForum is the net's largest birding community dedicated to wild birds and birding, and is absolutely FREE!

Register for an account to take part in lively discussions in the forum, post your pictures in the gallery and more.

Reply to thread

Message: <blockquote data-quote="WJC" data-source="post: 3166680" data-attributes="member: 25191">:cat:O_N:Yes, thermal cells make a difference, even in hand-held binoculars. Even so, while it is a topic to know about, it is certainly not one to fret, or waste words over—at least as far as bird watching is concerned.“Scientists have been aware of optical turbulence since English naturalist Robert Hooke in 1665 attributed the twinkling of stars to "small, moving regions of the atmosphere having different refracting powers which act like lenses." Astronomer William Herschel was aware of optical turbulence and explicitly adopted measures to cope with it, and observational analyses of the problem appear in the late 19th century . . .  Observatory astronomers around 1900 had identified atmospheric turbulence as a ‘FACTOR OF PRIME IMPORTANCE’ . . .” I notice you poo pooed another of my assertions recently over on another thread. Thus, would I be out of line in asking you to post your specific optical credentials (other than your readings and amateur repairs) on the forum for all to see? When I returned to this forum, you seemed to need to put your stamp of approval on what I said, or else lambast and correct me—“I tried, I really did.” I’m not unfamiliar with this modus operandi. There is someone on Cloudy Nights with the same agenda. If I could lay my sword on his shoulder and give him my experience, I would; maybe then I could have some peace. He has only been successful in stealing it with newbies and non-English speakers. But, he keeps trying. So, I will leave you to build your fiefdom; I’m just trying to help. So, considering I have been severely and unkindly warned that to be here I must let you walk all over me and waste my time defending what I know to be true, I will leave you to your own devices. :cat:Cheers,Bill PS Have another 100 feet of rope, on me.</blockquote>

Verification