File:NGC7000 (-2) center (4144732481).jpg

Subject: NGC7000/IC5067/IC5070 -- North America Nebula and Pelican Nebula

Image FOV: 3.666 degrees by 3.333 degrees (220 minutes by 200 minutes)

Image Scale: 10 arc-second/pixel

Date: 2008/07/25 (H-alpha), 2008/08/02 (RGB)

Location: near Halcottsville, NY

Exposure: H-alpha E:12 x 10 minutes, H-alpha W: 12 x 10 minutes, RGB E: 6 x 10 minutes, RGB W: 6 x 10 minutes, total exposure = 6h, ISO800, f/4.8

Filter: H-alpha: Baader 7nm, RGB: Astronomik UHC

Camera: Hutech-modified Canon 30D

Telescope: SV80S 80mm f/6 + TV TRF-2008 0.8X reducer/flattener = 384mm FL, f/4.8

Mount: Astro-Physics AP900

Guiding: ST-402 autoguider and SV66 guidescope. MaximDL autoguiding software using 6-second guide exposures (H-alpha) and 3-second guide exposures (RGB -- bright star in field caused blooming at 6 seconds)

Processing: Raw conversion and calibration with ImagesPlus (dark frames, bias frames, and flat frames); Aligning and combining with Registar; Levels, cropping/resizing, JPEG conversion with Photoshop CS. No sharpening or noise reduction. Mosaic created with Registar and Photoshop. Final image channels: Red = max(UHC red, H-alpha red), Green = max(UHC green, 0.33*H-alpha red), Blue = max(UHC blue, 0.25*H-alpha red)

Remarks: [H-alpha E]: Temperature at start 55F, SQM-L = 21.42 at start, 21.46 in middle, 20.99 at end (moonrise) [H-alpha W]: Temperature at end = 49F, SQM-L = 20.75 at start (moonrise), 20.36 at end (moon was up)