After a week of frustrating weather, with a cut-off low wandering around California aimlessly and messing up our skies, finally on Tuesday Oct 17 we had perfect weather and I had a free night. I drove up to Coast Ranch Reservoir Rd with a clear horizon to the northwest. The comet was 20 degrees above the horizon when darkness arrived. The comet has receeded from the sun while approaching the earth, and the tail that was so spectacular in images in late September, had faded quite a bit. It was moving about 2 arcmin per hour and 5 minutes was about the limit to avoid noticable blurring due to motion within a single exposure. The comet was 12 degrees above the horizon at the last exposure
10x5min stack using the ST2000XCM and Megrez f/6 refractor. sRGB+gamma/ single-shot color processed in CCDOPS 5. The upper right suffered from chip condensation for the first few frames. Aligned and stacked on the comet nucleus in Registax3. Then Photoshop CS2 used for levels, cropping, "smart sharpening", and pump up the color saturation slightly |
The DumbBell Nebula (M27) in Vulpecula. 4x5min stack using the ST2000XCM and Megrez refractor, sRGB+gamma/single-shot color processing in CCDOPS5, stacked in Registax3. Levels, "smart sharpened", unsharp mask, despeckled, and severely cropped in Photoshop CS2. |
Friday night Oct 27 I cancelled the Mercey Hot Springs trip due to lack of interest, and drove up to Coast Road Reservoir. Last minute helper was my friend Victoria. Outstanding weather, and I tried this time to get shots through the LXD75 8" f/4. Unfortunately, the 1.25" adapter makes a poor mate with the LXD75's 1.25" adapter, and the image plane was not co-planar with the chip. Still, the increased aperature made for a striking image, even with the 30% moon providing a strong skyglow.
10x5min stack with ST200XCM and Meade LXD75 8" f/4 scope. Stars badly out of focus towards lower left. Head is badly over exposed (there must be some way to get around the CCDOPS5 conversion of the raw image to color using only 8bits). Image scale is around 40% less than with the Megrez and the comet moved significantly during the hour and a half of exposures, resulting in the banding seen at top. Registax had a hard time centering on the saturated comet head so the star tracks are uneven and the tail details are blurred. Lesson - shorter exposures! |