Re: [ATM] Mirror movement in a Newton gives bad guiding ?

["Bob May" <bobmay@nethere.com>]

Guiding is going to be a problem when the same light path isn't used for
both guiding and imaging.
There will not only be problems with the mirrors shifting but also the
bending of the various parts of the scope as the exposure goes on.
One thing that has helped with the CCD imagers is that the exposures are
generally a lot shorter than with film cameras and this means that the
possibility of the movement of the image is lessened.
The only way to cure this problem list is to track a star that is on the
edge of the image, hopefully out of the view of the imager, and that means
that you will be tracking the image with the guider.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net


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