Science Buddies: "Ask an Expert"

I'm doing the project Using a Digital Camera to Measure Skyglow (https://www.sciencebuddies.org/science- ... ow#summary) and it asks for a a 30 second long exposure to take a picture of the night sky. The best I have is a camera with an 8 second exposure time. Would that be enough, or should I search for something with better exposure?

Hello colleenpolka,

Your camera with the 8 second maximum exposure time may work. To find out you'll need to do a quick test before starting your experiments. In this test you should check to see if your camera can produce a usable photo at the location you selected with the brightest skyglow.

Visit the location from your list that you think has the brightest skyglow. Take a look at the part of the project procedure under the heading “Taking Skyglow Photos”. Follow steps 4 through 6 that describe how to take your photos. At step 4e set your shutter speed to 8 seconds (max. for your camera) instead of the 30 seconds shown.

Examine the photo as described in step 6 a. If you have a usable photo (not completely or mostly white) with the 8 second exposure then your camera will work. Or if you need to reduce the exposure time to get a good photo your camera will work.

I hope this helps. Please ask again if you have more questions.

A. Norman

Thank you for your help! The camera did end up working.