How To Photograph Long Exposures At Night
The earth rotates at around its axis 1,000 miles per hour and hurtles around the Sun at about 70,000 miles per hour, yet the stars in the distance seem to creep idly by every night. When deciding on what maximum exposure time should be used these Astro bodies can be challenging for those trying it for the first time. For astronomical photos of the Moon’s surface, usually, the Looney-11 rule is a great starting point (f/11 and shutter speed to ISO setting). Similar to the Sunny-16 Rule, it allows for sharp well-exposed images without a light meter. Star trails can be a desired effect, but for images of the stars-as-dots, the 500-Rule should be followed.
The 500-Rule states that to obtain a clear image of stars without trails, take the number 500 and divided it by the focal length to get your exposure time. For example, a 20 mm lens would call for an exposure of about 25 seconds and theoretically, still obtain the stars without trails. The team over at Mango Street demonstrates the 500-Rule in their quick tutorial that will help you get sharp images of the sky at night, even if you haven’t shot Astro-landscapes before.
Provided you have the right equipment, it mostly comes down to tweaking your camera settings. A wide fast lens, such as the Tamron 15-30mm f/2.8, are fantastic for capturing images sharp clear images. Another useful tip is to avoid light pollution from major metropolitan areas. Sites like Dark Site Finder help you find the area closest to you that has the minimal amount of pollution, though sometimes it is hours away it can be worth it especially if you have never witnessed the full splendor that is the Milky Way.
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