Terrible how?  Do they look "blurry"?  Keep in mind that due
to earth's rotation, the moon will "move" in the celestial
globe.  An exposure of a few seconds *at high magnification*
may show significant motion blur to make the image look
not-so-good (even if it may not be obvious that it is
motion blur what we see).

Notice that I used my telescope with the motorized tripod
(which BTW, does not go at the exact speed of the moon, but
the difference is negligible perhaps up to a few minutes
exposures -- which is never the case anyway).  In some
cases, I used the telescope optics as the lens (for an
effective 1000mm f/5 lens), and in other cases I used the
300mm ED f/4-5.6  (the same you used) but having the camera
attached to the telescope (piggybacked to the optical tube).
That means that the camera was moving to track the stars
and moon movement.

Another possibility, if it is simply that the color in your
images didn't come out as vivid, is that the atmospheric
conditions at your location were not as good as here -- in
Montreal, that night the sky was *particularly* clear and
the air (wind) was particularly calm;  for pictures at that
magnification and "against all odds", the atmospheric
conditions may be critical.   Were you near downtown in
a big city or some place where there was air pollution?

In any case, I'm glad you enjoyed these shots!

Cheers,

Carlos
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