Conditions were terrible: a very bright Moon (which really doesn’t matter for Hα but matters for finding things) and lots of clouds combined with lots of haze. I tried to start on the Elephant's Trunk Nebula but could not find any asterisms nor could I see it after 300 s) so I came back to the Crescent where I knew I could see the parallelogram of stars. It was even a little bit difficult to find Sadr to sync (clouds and haze being the main culprit). 600 s subs are still barely sufficient. Warm; started at 24.5 °C and the chiller got it down to about 14-17 °C (it was drifting down through the night). Did a meridian flip and continued. The power of Hα is evident in that I got anything useful out of such poor conditions. It will be nice to get some Hα on a good night! I’ll have to hunt around for some RGB at this same scale to try combining.
Date: 8 Aug 2014
Subject: NGC 6888, Crescent Nebula
Scope: AT8IN+0.5x Antares telereducer
Filter: Baader Planetarium 7 nm H-α
Mount: CG-5 (Synta motors, PicGoto Simplificado)
Guiding: 9x50 Finder/Guider + DSI Ic + PHD 2.3.0 (Win 7 ASCOM)
Camera: DSI IIc chiller at 2.50 A, 14-17 °C
Acquisition: Nebulosity 3.2.0, no dither
Exposure: 23x600 s
Stacking: Neb 3, bad pixel map, bias included, extract R, resize 2x, normalize, trans+rot align, 1.5 SD stack.
Processing: StarTools 1.3.5.279 Crop; Wipe:Color & brightness 75%; Develop 74.99%; HDR
ptimize; Deconvolute 2.7 pix; Life:Moderate; Track RNC 0.25%; Magic:Shrink 1 pix. CS6 AstronomyTools B&W to Hα; layer masked deep space, space noise reduction; Astro Frame.
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