I opened the observatory Tuesday, 27 December, at 1807 MST, 55°F. As seen in this photo showing Venus and the crescent moon:

there were some clouds in the western sky. However, I wanted to try imaging of NGC7048, a small (about 1 arc minute), faint (Magnitude +12.1), planetary nebula in Cygnus. I had done a 1 minute, unguided exposure on the previous night. I needed to do a longer, guided, exposure and with Cygnus getting lower in the west each night and with the moon getting brighter each night, this could be my last opportunity to image NGC7048 for some months.

At 1813 MST, I viewed Venus in the 8" LX200-ACF, through the thin clouds, at 77X. I then took a quick look at the moon, also in the clouds, 77X. Seeing was obviously lousy but the crescent moon and Earthshine were pretty. I then began making preparations for the DSO imaging.

I attached the D7000 DSLR at prime focus using the Off-Axis Guider (OAG). Slewed to the star Deneb, did a rough focus, and SYNCed the AutoStar. I then slewed to NGC7048 and looked for a guidestar. There was a faint one in the OAG illuminated reticle eyepiece, so I knew I could do a guided exposure. I then slewed back to Deneb and began waiting for twilight to end, all the while watching the movement of the clouds. The light from the crescent moon would not be a problem, but the clouds might be.

At 1840 MST, with the clouds moving towards Cygnus, I decided the sky was dark enough to start imaging. I did a focus test on Deneb using the Bahtinov Mask. I then slewed to NGC7048 and found a brighter guidestar to use. I did a 1 minute, ISO 6400, unguided, framing test exposure. It was good, so I began a 5 minute, ISO 6400, guided, exposure.

Shortly after completing the 5 minute exposure, the clouds were getting close to Cygnus. I debated whether or not I had time to try a 10 minute exposure. I studied the 5 minute image on the camera screen and decided it was good. Closed the observatory at 1920 MST, 47°F.

I have been testing a pretty amazing image noise reduction software product called "Neat Image" and used it on the (cropped) 5 minute, ISO 6400, guided, exposure of NGC7048. This is the result (move your mouse over the image to see an unprocessed comparison image in place):

I have now posted a review of "Neat Image" on my ETX Site. There are free and paid versions available. Check out my review for more details and examples using some of my DSO astrophotography to see just how well "Neat Image" does at noise reduction. I have re-processed many of the images in the Cassiopeia Observatory Photos albums using "Neat Image" and have updated them online.

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