----- Original Message ----- From: "captgww" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, March 31, 2004 5:22 AM Subject: EOS Lens eyepiece
> Is there an eyepiece that fits on an eos lens to make it useful as a > telescope?? Have never seen one for the EF range. I have such a device for my Minolta MF lenses (MC &MD). It's got a focal length of 10mm and some sort of prism (perhaps ?) to give an upright image. So a 200mm tele becomes a 20x telescope etc. Is it useful? No way, in my opinion. It's simply too difficult holding the combo still to get a clear view. And taking the 200mm lens example again, assume an aperture of f2.8 we get a clear opening of 71.4mm. Divide by the magnification, 20x, and we get an exit pupil diam. of ~3.6mm. Not too bad, but it's difficult to hold adequately still without tripod support. Not one of my treasured purchases! Malcolm Milton Keynes, UK www.megalith.freeserve.co.uk/oddimage.htm http://myweb.tiscali.co.uk/ms1938/ * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
