Quote:
Originally Posted by macditto
There is no right or wrong answer here. The higher the multiplier the better the sampling and the closer the image reflects what was received down the OTA. A higher multiplier will always give a better result but it is a law of diminishing returns. But I can tell you from the planetary work I have done that 2X is not enough and 3X is closer to the money. And the question of sampling applies to all forms of astro-imaging including deep sky, since it is just the translation of a photon stream to an image.
The following DropBox link to a planetary image shows the difference in resolution on a planetary image with sampling at a 2.2X multiplier compared with 3.3X. The difference is huge.
https://www.dropbox.com/s/rcai6pwhkz...tions.jpg?dl=0
The 2X multiplier developed by Nyquist was for sound which is a one dimensional array. A 2D array such as an image needs 3X or more, so that the fidelity of the resultant image is not discernible from that potentially coming down the OTA.
Cheers, Niall |
You're right -
if Mike was using say a 2x coma corrector he would have
an arc second/pixel ratio of 0.42 asec/pix and a more reliable measurement
which could be compared to say CHART32 and other sites.
cheers
Allan