dkCambridgeshire Posted April 25, 2016 Share #1 Posted April 25, 2016 (edited) Advertisement (gone after registration) Last Saturday discovered that my ancient c.1995 APO fluorite ‘Vixen’ Super Polaris 810mm f9 astro refractor telescope will take a T2 adapter after removing part of the focuser - thus used it on the dull but windy day with my Leica T camera and Leitz APO 1.4 and 2x extenders. These are straight JPEGS with no post processing apart from resizing to 1280mm width and reducing file size. The 'scope was mounted on a Zone 6 wooden tripod but could not find a 3/8 to 1/4 adapter - so unable to use an additional long lens support. The set-up was not at optimum steadiness but was sufficiently steady after setting ISO 3200 and using the camera's self-timer. The out of focus foreground 'blob' is part of a garden shrub, Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 810mm x1.5 crop factor = 1215mm FF equivalent The lens has potential and is certainly better than my mirror lenses - but is not much different as regards focal length to my Leitz 800mm . The estate agent's sign is 82m distant from my back door - measured using a Leica electronic rangefinder. cont'd … Edited April 26, 2016 by dkCambridgeshire Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 810mm x1.5 crop factor = 1215mm FF equivalent The lens has potential and is certainly better than my mirror lenses - but is not much different as regards focal length to my Leitz 800mm . The estate agent's sign is 82m distant from my back door - measured using a Leica electronic rangefinder. cont'd … ' data-webShareUrl='https://www.l-camera-forum.com/topic/259730-ff-equivalent-3402mm-lens-experiment/?do=findComment&comment=3033442'>More sharing options...
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dkCambridgeshire Posted April 25, 2016 Author Share #2 Posted April 25, 2016 (edited) Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 810mm x 1.5 crop factor x 1.4 Leitz APO extender = 1710mm FF equivalent cont'd ... Edited April 26, 2016 by dkCambridgeshire Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 810mm x 1.5 crop factor x 1.4 Leitz APO extender = 1710mm FF equivalent cont'd ... ' data-webShareUrl='https://www.l-camera-forum.com/topic/259730-ff-equivalent-3402mm-lens-experiment/?do=findComment&comment=3033444'>More sharing options...
dkCambridgeshire Posted April 25, 2016 Author Share #3 Posted April 25, 2016 (edited) Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 810mm x 1.5 crop x 2 Leitz APO extender = 2430mm FF equivalent cont'd …. Edited April 26, 2016 by dkCambridgeshire Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 810mm x 1.5 crop x 2 Leitz APO extender = 2430mm FF equivalent cont'd …. ' data-webShareUrl='https://www.l-camera-forum.com/topic/259730-ff-equivalent-3402mm-lens-experiment/?do=findComment&comment=3033445'>More sharing options...
dkCambridgeshire Posted April 25, 2016 Author Share #4 Posted April 25, 2016 (edited) … and finally with stacked extenders: Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! 810mm x 1.5 crop x 1.4 x 2x Leitz APO extenders (stacked) = 3402mm FF equivalent Stacked Leitz 1.4x and 2x extenders i.e. 2.8x, push the combination - but surprisingly they do work reasonably well - and will probably give a sharper result when additional supports are used. The experiment will be repeated in better light using two tripods and a small fork support attached to a Manfrotto long lens support. Please note the in-camera JPEG images were deliberately not post processed or sharpened. Hopefully the experiment has paved the way for some more interesting long distance cityscape imaging in the near future. The Vixen fluorite 'scope is not cheap to buy - but it's considerably cheaper than a marque 800mm camera lens. The only downside is its fixed f9 aperture - but with a mirrorless camera that is no handicap. The 'scope is a two element design comprising one crown glass and one fluorite - the artificial fluorite made by a Canon subsidiary in the 1990s. Cost of the 'scope in the 1990s when new was $1750. They are still sought after and can be purchased s/h for c. $900 to $1200. Regards dunk Edited April 26, 2016 by dkCambridgeshire 4 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! 810mm x 1.5 crop x 1.4 x 2x Leitz APO extenders (stacked) = 3402mm FF equivalent Stacked Leitz 1.4x and 2x extenders i.e. 2.8x, push the combination - but surprisingly they do work reasonably well - and will probably give a sharper result when additional supports are used. The experiment will be repeated in better light using two tripods and a small fork support attached to a Manfrotto long lens support. Please note the in-camera JPEG images were deliberately not post processed or sharpened. Hopefully the experiment has paved the way for some more interesting long distance cityscape imaging in the near future. The Vixen fluorite 'scope is not cheap to buy - but it's considerably cheaper than a marque 800mm camera lens. The only downside is its fixed f9 aperture - but with a mirrorless camera that is no handicap. The 'scope is a two element design comprising one crown glass and one fluorite - the artificial fluorite made by a Canon subsidiary in the 1990s. Cost of the 'scope in the 1990s when new was $1750. They are still sought after and can be purchased s/h for c. $900 to $1200. Regards dunk ' data-webShareUrl='https://www.l-camera-forum.com/topic/259730-ff-equivalent-3402mm-lens-experiment/?do=findComment&comment=3033448'>More sharing options...
dkCambridgeshire Posted April 26, 2016 Author Share #5 Posted April 26, 2016 (edited) Forgot to mention that the f9 aperture becomes smaller with extenders: With a 1.4x = f12.6; with 2x = f18; with stacked 1.4x plus 2x = f25.2. Plan to use the lens for long distance 'cityscape' photography - as per recent Alexandra Palace experiment using my SL 601 and Leitz 800mm Telyt S http://www.l-camera-forum.com/topic/258931-leitz-800mm-telyt-s-with-the-sl/?p=3026808 dunk Edited April 26, 2016 by dkCambridgeshire 1 Quote Link to post Share on other sites More sharing options...
david strachan Posted April 26, 2016 Share #6 Posted April 26, 2016 Good work Dunk. Some moon shots next...the ultimate challenge. 1 Quote Link to post Share on other sites More sharing options...
dkCambridgeshire Posted April 26, 2016 Author Share #7 Posted April 26, 2016 Advertisement (gone after registration) Moon shots are planned too dunk 1 Quote Link to post Share on other sites More sharing options...
LocalHero1953 Posted April 26, 2016 Share #8 Posted April 26, 2016 My house points towards Peterborough. I can see I'll have to start closing the bedroom curtains......... Quote Link to post Share on other sites More sharing options...
lanetomlane Posted May 10, 2016 Share #9 Posted May 10, 2016 Wow!!! Quote Link to post Share on other sites More sharing options...
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