On a slightly hazy night of rather good (albeit not perfect) seeing, I tried to "push the magnification" of my C6.
Now, 3000 mm of FL with 2.4 um pixels is rather in the oversampling range, albeit from what I read about the Nyquist Theorem, there is not a clear definition of the absolute upper boundary of sampling.
Indeed twice the theoretical resolution is just the "minimum" optimal sampling AND which resolution anyway?
Rayleigh, Dawes, Sparrow are good for double stars of equal magnitude, but what about lines-like object like rilles (or, famously, the Cassini division) or point-like object like very small craters or satellites?
So I think it is worth to try to push the envelope and see if something unexpected or, rather, not commonly considered, comes out.
Not this time apparently, since I do not think I got new details in this image I did not get in older images of the same subject.
Also, artifacts become only more manifest.
Probably 2100 mm with the 178MM is about the maximum for the C6, except perhaps for super seeing 1+ nights, the like of which I have seen so far only once in my life.
That said a bigger image has some advantage for an ageing eyesight like mine, but probably magnification through interpolation would give the same result.
P.S.
After comparing the diameter of Ptolemaus in this image with its size in
this image taken at the native FL of 1500 mm, it would look like the effective FL of the image above is more like 3750 mm.
However, SCT focal length is indeed variable depending on the position of the sensor AND the Moon-Earth distance varies in time, so one cannot really say with absolute certainty.
Comments