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Thread: Is winter truly better for imaging compared to summer?

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    Default Re: Is winter truly better for imaging compared to summer?



    It is all about temperature. More heat, worse seeing and warmer cameras.

    Nothing to do with what is up in the sky.

    Nothing to do with humidity.

    Nothing to do with North vs South.

    Temperature affects North and South the exact same way.

    Overnight temperatures in Alice Springs or Uluru (the proper name of Ayers Rock) in summer can still drop close to zero C, and it is very dry. During winter, humidity is actually higher there. But it all depends on the rain too.

    I've been at Uluru during January. During the day the heat is something, but because it is dry it is bearable. But because it is dry, transparency is outstanding! Now, if you had a scope, you would notice something else - a boiling sky - until it cooled down enough a few hours after sunset.

    The time it takes things to cool down affects not only seeing but productivity too.

    I had never seen as many meteors as those few nights. Never before and never since!

    Oh, I was also fortunate to get to touch Uluru at the crack of dawn - it was still HOT even after eight or nine hours of night!

    Alex.
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    Default Re: Is winter truly better for imaging compared to summer?

    Quote Originally Posted by mental4astro View Post
    It is all about temperature. More heat, worse seeing and warmer cameras.

    Nothing to do with humidity.

    I've been at Uluru during January. During the day the heat is something, but because it is dry it is bearable. But because it is dry, transparency is outstanding! Now, if you had a scope, you would notice something else - a boiling sky - until it cooled down enough a few hours after sunset.

    Alex.
    Sorry, I'm a bit slow here, Alex .. So if humidity is low, and it IS dry, and transparency is outstanding, then humidity is STILL in the picture no?

    In all likelihood, I wont bring my EQ gear or a scope; just the SkyGuider Pro or LighTrack and a couple of lenses.
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    Default Re: Is winter truly better for imaging compared to summer?

    Low humidity = dry

    High humidity = muggy, damp, oppressive, even dew

    So, low humidity, dry conditions = superior transparency

    This is one of the bonus consequences to taking the time and effort to find locations that are optimal for astronomy. A dew free site means the absence of the associated mist that comes with it and hence improved transparency.

    But this is not the nub of the reason for why winter is better than summer. Improved seeing comes with reduced temperature (though not the only way seeing is improved). Your question really is just about the temperature differential between summer and winter. The question of humidity is a separate one. Local seasonal climate and geography affect affect humidity.

    Confused?
    Last edited by mental4astro; 02-15-2018 at 03:54 AM.
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    Default Re: Is winter truly better for imaging compared to summer?

    Quote Originally Posted by mental4astro View Post
    Low humidity = dry

    High humidity = muggy, damp, oppressive, even dew

    So, low humidity, dry conditions = superior transparency

    This is one of the bonus consequences to taking the time and effort to find locations that are optimal for astronomy. A dew free site means the absence of the associated mist that comes with it and hence improved transparency.

    But this is not the nub of the reason for why winter is better than summer. Improved seeing comes with reduced temperature (though not the only way seeing is improved). Your question really is just about the temperature differential between summer and winter. The question of humidity is a separate one. Local seasonal climate and geography affect affect humidity.

    Confused?
    Kinda LOL, but I think I'm getting there .. Having grown up largely in the tropics except for a 3-year stint in England, I've always been exposed to high temperatures and humidity. So it would appear that in 1 locality say Uluru, regardless of whether it is summer or winter, it is quite consistently dry so transparency is great. But winter brings along improved seeing as well and that's why it'd be considered as a killer astro site?

    If this is so, then even EITHER good seeing or better transparency would already be tons better than what I'm used to .. would this be a correct assumption? And if this is true, then even going in spring would still be tons better than in Malaysia since I'll probably still have great transparency with average seeing?
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    Default Re: Is winter truly better for imaging compared to summer?

    Correctamundo all round!
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