Spiral Galaxy in Triangulum



M33: This is a very bright, 6th magnitude galaxy in Triangulum, between two and three million light years from Earth. It is perhaps sixty thousand light years across. Being relatively close to us, it has a huge apparent size; a full image would be several times the size of my CCD chip. Shown here is the central region; the bright part at the center of the image is the core of the galaxy, and several arms can be seen spiraling off from the core. Numerous dust lanes can be seen as well.


Technical Information:

LLRGB: 192:60:60:96 (Luminance layer consisted of 24 eight minute images; R and G comprised of 6 ten minute images; B comprised of 6 sixteen minute images). L images unbinned; R, G and B binned 2x2.

Equipment: 10" LX200 at f/6.1, and an SBIG ST-8E camera/CFW-8 color filter wheel, guided by an SBIG AO-7 adaptive optics device, guiding at about 21 Hz for Lum, about 10Hz for RGB.

Image Acquisition/Camera Control: CCDSoft V5.

Processing: All images calibrated (darks and dawn flats) and registered in AIP4WIN. Images average combined in Ray Gralak's sigma reject program. Three iterations of Richardson-Lucy applied in CCDSharp. Iterative applications of curves, levels and brightness/contrast in Photoshop 6.0, followed by a gentle unsharp mask in Photoshop. Color combine performed in Photoshop 6.0.

Location: My yard in Redmond, Washington, elevation 500'.

Date: Luminance images taken during the night of 10/31/02; RGB images taken during the night of 11/1/02.

CCD Temperature: Lum: -33C; RGB: -30C

Moon Phase: Waning crescent

Copyright Mark de Regt, 2002