Light Pollution
Late in the evening of July 27th a cold front temporarily cleared away cloudy skies that had lasted continuously for the past two months. Moonlight was not a problem, but hazy conditions from wildfire smoke and neighborhood light pollution made observing conditions less than ideal. Almost no stars were visible below 40 degrees altitude. Nevertheless, I set up my Seestar to see what was possible. Initially, I planned to try capturing some targets in Sagittarius which had risen reasonably high in the south. Unfortunately, one of my neighbors has a back yard located to the south directly beneath Sagittarius. The neighbor's yard was completely lit by a set of party lights adding to the light pollution.
My first target was the Omega Nebula, M17, in Sagittarius. With Seestar's light pollution filter engaged I managed to get the following image after 5 minutes of effective exposure.
I say 5 minutes of effective exposure because the image above is the result of stacking 30 ten-second exposures. It took much longer than 5 minutes to obtain these 30 exposures, however, because Seestar kept rejecting bad exposures caused by poor tracking. After roughly 30 minutes watching exposure after exposure rejected, I gave up and settled for the 30 accumulated good exposures. As usual I'm disappointed in the color Seestar produces for emission nebulae. I can't seem to reproduce the bright red I see in pictures made by experts.
Next I moved to open cluster M7, also in Sagittarius. The same tracking problems happened with M7, but 5 minutes of exposure was enough to show this pretty star cluster nicely as you can see in the next image.
After midnight I was running out of energy. Since tracking seemed improved in the Cygnus sky area, I decided to try one last target there - the Eastern Veil Nebula, NGC6992. The entire Veil Nebula is a shock wave from the supernova explosion of a massive star about 10,000 to 20,000 years ago. It is a large, roughly circular supernova remnant about 3 degrees in diameter, much too large to fit within Seestar's field of view. The entire nebula is so big that its brighter segments have separate names. The Eastern Veil Nebula shown next is one of the brighter segments. I was amazed to see it show up in the following 15-minute exposure made with the light pollution filter engaged.
Once again, I'm disappointed in how colors are displayed. It's also possible the lens may have been fogging with dew because I hadn't turned on the lens heater. This object is a good candidate for a longer unfiltered exposure on another night with better sky conditions.
I enjoyed using Seestar again after two months of impossible observing conditions.
