Last night I was finally able to go out and try and observe and image the new comet (C2022 E3 ZTF). The Moon was very bright which made spotting the comet difficult. I started by doing a 3 star alignment on my CEM120 mount. I then used Skytools4 on my computer to connect to the mount and command it to slew to the comet. The slew was off just slightly but I was able to find the comet. Using 11 inch SCT and 40 mm eyepiece I could easily see the comet. It had a bright core and fairly large 'halo; I could not detect any tail. I then tried my Vixen 10x50 bino. I sighted down the barrel of the scope and easily found the comet in my bino. It was actually a decent sight, but still no obvious tail.
So I decided to try and image the comet. So I installed my ZWO ASI290 on the 90mm refractor for autoguiding, and installed ZWO ASI2600 on the 5 inch refractor for imaging. After PHD2 calibration, guiding was good. Used SGP to connect all equipment and manage the process including focusing.
I started taking 1 minute exposures. The comet was very bright in the 1 minute exposure. After taking several images it became apparent that the comet was moving so fast that I would not be able to stack the comet images without blurring the comet. So I decided to try my luck at various exposures, 10 sec, 15 sec, 30 sec, 1 minute. My plan was to maybe process enough to show comet movement.
But I still wanted at least one decent image of the comet. So I took one of the 1 minute exposures and decided to do my best with PixInsight.
I recently added processes from Russell Croman Astrophotography for deconvolution, noise reduction, and star removal. I also added the new Generalized Hyperbolic Stretch function. I find these tools so valuable that I am in the process of re-processing many of my older images...by I digress.
Using only a single 1 minute exposure I went through my normal image processing routine without having to perform all of the steps leading to 'stacking'. I then used the new SpectroPhotometricColorCalibration tool to perform color balance, the BlurXterminator tool to do deconvolution, the NoiseXterminator tool to reduce noise, and the StarXterminator tool to make a starless image and an image with only stars. This allowed me to work on the comet totally independent of the stars. At that point I used the GeneralizedHyperbolicStretch function to perform the stretch. Then I used 'curves' to enhance and a MultiScaleLinear transform to sharpen. I then went back to the 'stars only' image and used HistogramTransform to stretch. Lastly I used PixelMath to add the two images together.
Sounds like a long process but it took about 30 minutes.
So ... here it is... not bad for a single 1 minute exposure. And it really is green!! I plan on working with other images and maybe try to generate a time-lapse video.
Roger
- Comet_C2022_E3_ZTF.jpg (15.66 MiB) Viewed 852 times
