This is a test.
Now that I have auto-guiding in right ascension, I am entertaining the thought of capturing narrowband at bin 1. I had been using bin 2, but the quality is never as good, even if I drizzle afterwards.
Unfortunately I can't auto-guide in declination, so exposures are pretty much limited to 240 seconds. I really want the sky background to be significantly higher than my sensor's Bias level. My Bias is 220 ADU. In this image the sky is 280 ADU. For me, that is just not high enough to adequately capture faint wisps of nebulosity given my Read Noise of 5.3 electrons. Decisions, decisions!
The following image is: Ha 6nm 25x240s
Total Integration Time: 100 minutes
Brian
NGC 6888 (Crescent Nebula) in Hydrogen Alpha
Forum rules
Please upload large images to photo sharing sites (flickr, etc) rather than trying to upload them as forum attachments.
Please share the equipment used and if possible camera settings to help others.
Please upload large images to photo sharing sites (flickr, etc) rather than trying to upload them as forum attachments.
Please share the equipment used and if possible camera settings to help others.
NGC 6888 (Crescent Nebula) in Hydrogen Alpha
- Attachments
-
- NGC-6888_Ha-25x240s-b1_v2.jpg (941.03 KiB) Viewed 777 times
Re: NGC 6888 (Crescent Nebula) in Hydrogen Alpha
Cool ...
Dave
Dave
Re: NGC 6888 (Crescent Nebula) in Hydrogen Alpha
hehe, thanks Dave. I love that music.
Brian
Brian