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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

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  1. B

    Observing the Moon with a spotting scope

    That is interesting. I don't know why this should be if the telescope is capable of 300x. It could be so in evening observations, but in my experience the best Seeing is at 3a.m. My 52cm Newtonian could not take high magnifications, despite the main mirror being 1/20 wave. This was because it...
  2. B

    Observing the Moon with a spotting scope

    The Local Seeing conditions depend on whether one is observing on concrete, or asphalt or near garages or buildings. Grass or fields are better. The position and speed of the jetstream are important factors and whether the temperature changes much from day to night. In the U.K. we are...
  3. B

    Observing the Moon with a spotting scope

    It is not just my eyes. Rev Dawes of the Dawes limit used 420x for his drawings of Mars and Jupiter and its moons. With his fine 6.3 inch refractor. He saw detail on Jupiter's moons, which I haven't. He was, I think, very short sighted and could not recognise friends walking by. My starting...
  4. B

    Observing the Moon with a spotting scope

    With a spotting scope, maybe, but not with an optically excellent astro scope. My Pentax 100mm f/12 certainly was used visually on planets at 300x and tested at 400x. The image did not break down at 0.25mm exit pupil. Even large telescopes do well at 0.5mm exit pupil. My 317mm Dall Kirkham...
  5. B

    Observing the Moon with a spotting scope

    With high magnification and small exit pupils astigmatism is less of a problem. There is a discussion of this somewhere but I cannot remember where. Regards, B.
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