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Post by Deleted on Jun 26, 2015 2:11:03 GMT
Sorry if I misspoke, but my 6" is an achro not an APO so I will be using Ken's technique to eliminate the false color when using my Jr Pro. I've not yet gotten my Canon to work with live views. Those are real nice images, Richard. Love the round stars. I can't get anything close to that. Hi Rick,
Like fashions, everything comes around again.
For the older astro nuts among us who cut their teeth on achromatic scopes back in the 60's, using a Wratten No 12 Yellow or Yellow /Green filter was standard practice to reduce the colour fringing, something that newcomers in the 21st century barely know about, so it is good to see the old tips coming to light again. I still have a large collection of the whole range of 2" square Kodak Wratten filters from my scientific imaging days, now and again I drag one out for a specific purpose. Back in those days the reason most achromatic refractors were f/15 and very slow, was to keep chromatic aberrations to a minimum by the optical glass and designs of the day. This was the main reason I started building reflectors scopes and grinding mirrors & optical flats.
Clear skies... Shevill
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Post by Rick in NWArk on Jun 29, 2015 16:40:39 GMT
I agree, Shevill... and for video, I need a relatively short effective focal length versus the F/15 scopes. I drool over the D&G scopes from time to time. Even thought about convincing the wife that you could hang clothes on them to dry. Haha!
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Post by Deleted on Jul 1, 2015 3:23:58 GMT
I agree, Shevill... and for video, I need a relatively short effective focal length versus the F/15 scopes. I drool over the D&G scopes from time to time. Even thought about convincing the wife that you could hang clothes on them to dry. Haha! Hi,
Something very often overlooked for video astronomy are S/H C mount zoom video lenses and lenses for 35mm cameras, using a suitable adaptor. These are a lot faster wider FOV and a lot cheaper than telescopes.picasaweb.google.com/109921669020426367250/VideoAstronomy1988Present?authuser=0&feat=directlinkSome great cheap buys to be had on eBay and S/H photographic outlets, especially good are 42 mm screw mount Pentax 35 mm camera lenses. I use them all the time and have a case full of Super Takumar lenses from wide angle to telephoto.
Clear Skies... Shevill
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