Photography: What is the recommended settings for startrails?
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What is the recommended settings for star trails of about 20 minutes?
my equipment is a Nikon D5000
Nikon 18-55mm kit lens
Sigma 70-300mm
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LOw ISO (100 or 200)
f4-f5.6 - depends on the ambient light where you are.
Manually focus the lens at the wide focal length end.
Bulb mode with a remote release.
That's if you want to do one single long exposure. The better way is to do many 30sec - 1min exposures and 'stack them';
http://www.startrails.de/html/software.html
This will minimise long exposure noise and also saves you something if it goes pants & the camera fails.
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First, you'll definitely need a tripod and a locking remote release. You'll also need your camera to be in Manual Mode and with auto focus and VR turned OFF on your lens. This site will help you:
http://www.danheller.com/star-trails