M1
by Vern on Nov.23, 2005, under Astronomy, Deep sky, Diffuse Nebula
Thursday evening I set up the Stellacam2 along with a 0.33 focal reducer on the Nexstar11 and recorded M1 for half an hour. Stellacam was set to 8/14 gain and 256 integration. Sky was clear, turbulence 6/10, temperature 35 degrees F.
2 comments for this entry:
November 26th, 2005 on 10:20 am
A real nice image of M1. The image shows a lot of structure with varying degrees of brightness throughout, looking like parts of M42. The fact that the stars don’t appear pinpoint, does it have any effect on how M1 appears?
This object is difficult for us to see from the city, and recently seeing it was surprised how large it is. I wonder if we didn’t see the area where that ‘gully’ is to the lower left, and if it is visible to other observers under other conditions.
November 26th, 2005 on 3:50 pm
I’m only about 4 miles from the light pollution center of Denver so I have a tough time seeing it visually as well. The Stellacam2 is great to use in light polluted metro areas as you can see structure in deep sky objects such as M1 in near real time on the monitor. Also, its fun at public outreach events as a number of people intentionally bump the scope just to see if the image is actually “live”.
Lack of pinpoint stars probably isn’t much of a problem as there will always be some bloat from the brighter stars. However, the stars not being round is an indication of tracking problems, incorrect north alignment, wind vibration, turbulence, or scope collimation. Many of the stars in my image of M1 above appear to be oval-shaped in the upper left to lower right direction. I assume this is due to scope tracking error or not being accurately north aligned during the 8.5 second integration time. I checked scope colimation that evening, the seeing was pretty good, and there was no wind so I doubt those were causes. Any errors such as I have in this image will affect the amount of detail visible.
I’m pretty sure I did a sketch of M1 this fall from a dark sky site, unfortunately I can’t locate it at the moment. It would be interesting to see if I noted the “gully”.