In October, I got this fantastic picture of the Andromeda Galaxy from Dell City, Texas with its Bortle 2 – 3 dark skies.
Camera geek info:
- Canon EOS 60D in manual mode, 179 second exposure, ISO 1600, custom white balance 3500K
- Williams Optics Zenith Star 73 III APO telescope
- Williams Optics Flat 73A
- iOptron CEM40
- Dell City, Texas Bortle 2-3 dark skies
I wanted to see what happened when I used the exact same setup and settings from my driveway in Friendswood, Texas with its Bortle 7 (much much brighter) skies. My suspicion was that the picture would be all white.
On my first opportunity to try the experiment, there was also a two days past full Moon in the same section of the sky. As you can see, I did get an almost all-white picture.
I backed off to ISO100 to avoid overexposing the picture, but then I didn’t get near the detail that I got from the dark skies.
I didn’t know how much the overexposure was due to the near-full Moon and how much was due to light pollution.
Yesterday, I got the chance to try the experiment again with no Moon. As you can see, at the dark skies setting, I again got an almost all-white picture.
I backed off to ISO100 and ISO400 to avoid overexposing the picture, but again I didn’t get the detail I did under darker skies.
All of the pictures in this blog post are unprocessed, other than being saved to a lower resolution format. It will be interesting to see what I can get when they are processed.
How dark are your skies?
|Dell City, Texas||2 – 3||No Moon||3 minutes||1600||Gorgeous detail in M31, M32 and M101 visible|
|Friendswood, Texas||7||Near Full Moon||3 minutes||1600||Almost all white picture|
|Friendswood, Texas||7||Near Full Moon||3 minutes||100||M31 as a fuzzball, M32 and M101 not obvious|
|Friendswood, Texas||7||No Moon||3 minutes||1600||Almost all white picture|
|Friendswood, Texas||7||No Moon||3 minutes||100||M31 as a fuzzball, M32 and M101 not obvious|
|Friendswood, Texas||7||No Moon||3 minutes||400||M31 as a larger fuzzball, M32 and M101 barely visible|