Re: Why does older CoolPix-995 work with scopes, and DSLRs will not?- Very wrong statement!

Roy G wrote:

The Eyepiece lenses do not produce a "real" Image, It cannot be brought to focus outside the Telescope.


Wrong! Completely wrong, unless you are using a Galilean telescope that uses a negative lens for an eyepiece, and there haven't been many of those around in the last 400 years (I believe some really cheap binoculars still use this design). Of course an eyepiece can project a real image. I've projected the image of the sun onto a screen many times. The objective lens or primary mirror forms a real image in front of the eyepiece, and the eyepiece then can form a second, real image of that image somewhere beyond. Just think of the eyepiece as a simple, positive lens, with the telescope primary image on one side and the real image formed by that simple lens on the other side, outside the telescope. Though what this has to to with the subject at hand is another question. There is absolutely no reason a DSLR camera cannot be used in the same way as a small P&S, with the lens remaining in place. The problem isn't with the diamter of the lens, but its long focal length and the subsequent magnification you will get. As others have said, you could be much better off removing the lens (and maybe the telescope eyepiece if it is a long focal-length telescope) from the camera.

Sorry to jump on this, but I've been reading a lot of questionable statements in this thread, some clearly wrong. This was going too far for me, especially after saying someone should know better.

Joe
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