Wednesday, April 20, 2016
M27 - The Dumbell Nebula 20-Apr-2016
Distance 1,360ly, in Vulpecula
Telescope configuration: Celestron EdgeHD 1100 with the Celestron 0.7x focal reducer (fl=1960mm, f/7.0).
Camera: Nikon D5300. Exposures: 3 @ 5 min., Ambient temp 59f.
Image capture scale: 0.41 arc-sec/pixel (un-binned). Resized to 50% in ThumbsPlus. Final image scale/resolution 0.82 as/p. Field of view (horizontal) = 24.5 arc-min. Image capture using ImagesPlus Camera Control 6.0.
Mount: Orion HDX110 German equatorial mount. Autoguided with an SBIG Sti autoguider and a Celestron OAG (off-axis guider), with PHD2 autoguiding software, not dithered.
Post processing: ImagesPlus 6.5: NEF conversion and calibration, alignment, stacking/combining using 0 dark frames, a 5 bias frame master and 0 flat frames, Average combined. HDR Stretch, Curves and multiple enhancements in ImagesPlus. Cropped and resized to final dimensions, one pass unsharp mask, contrast, saturation, gamma in ThumbsPlus.