M_J_Helin Offline Upload & Sell: Off
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Thanks!
Travis Rhoads wrote:
Great images.
Question for you, about the Sigma 20ART...how do you control distortion of the stars in the corners? I love that lens, but it often ends up distorting the stars in the corners, exaggerating any movement in them. Your images don't seem to suffer from that, might be partially the shorter exposures.
Thank you!
Well, the short shutter speed helps for sure. Are you are aware of the rule of five hundred? By dividing 500 with the focal length of the lense you get the approximate maximum time you can use without star trails (using full frame). In this case it's 500/20= 25 seconds. But it depends on how close the (celestial) equator the stars are. So if they are very close, the time is a bit shorter (Orion for example). Then again the Big Dipper and other constellations near the north (or south) pole can take a bit longer exposure without trails emerging.
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