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Saturday, April 15, 2017

Temporary Neighbors

Shot with my Pentax K10D and a 500mm lens that cost me $50 on Craig's List.
 1/90th of a second, ISO 200.

1/90th second, ISO 100.

6 comments:

  1. Are you too busy to use your telescope?

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  2. Great shots, Clayton!! you guys will have to retuen to Alaska in the summer.

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  3. I take it this $50 lens is not an ED one as there is a lot of purple fringing one would not see on a quality glass telephoto, but then an ED one at that focal length could easily cost $5000 for a Canon/Nikon/Pentax lens (maybe half or so for a Tamron/Sigma ED one).

    Curious to know what f-stop/aperture you used and if it was the max for the lens. What brand/model lens is it? Lenses and especially non-ED ones usually have the lowest quality wide open.

    But for $50 not bad... ;-)

    I too am curious about the telescope question for taking pictures of terrestrial objects. Most celestial scopes stink for such a task. I have a mid 1980's Canon FD 800mm F5.6L lens (for 1970's and 1980's Canon SLR 35mm cameras)--a giant white telephoto lens (something like 12-16lb--forget the exact weight) and the kind seen at superbowls and world series games. I bought it in 1999 for $3,000 (new in '85 those were like $6K I think). It's ideal for terrestrial of course, but for celestial is it marginal except for Lunar where it is so/so. But then 800mm is only like 16x anyways. Another thing is terrestrial generally doesn't require lots of light gathering unlike a celestial scope.

    I need to get an FD to EOS adaptor and look into possibly have a conversion done to use a universal mount for digital, but I still have a case full of slide film in my fridge for years (sealed of course) I need to use up first.... I really want the current EOS IS 800mm Canon lens, but at $8,000-$10,000 for that beast unless I win the lottery (I never buy tickets though...odds stink)...

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  4. Also, aren't all your telescopes reflecting rather than refractor? Now refractors can be used like a telephoto lens, but they leave a lot to be desired compared to a real telephoto lens which is why one never sees serious amateur or pro photogs using a scope (besides issues like lack of autofocus, etc) for terrestrial imaging.

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  5. w: f/8, minimum. I will use higher f-stop in future. Don't remember brand and it isn't on it.

    I have used the 17.5" reflector experimentally for terrestrial photography. Like many short focus reflectors there is a bit of fogging from light sneaking in around the aperture. I have a 5" refractor which I have never used for terrestrial photography, because I put an optical corrector on it that turned an achromat with some color fringing into somewhat close to an apochromat, but it changes the focal point so much I can't get it in the camera body through the diagonal that has the threads for the corrector. I need to build something that holds the corrector in and one that isn't a diagonal.

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