NGC7640: This is a somewhat dim (magnitude 11.28) spiral galaxy in Draco, presenting to us edge on. It is generally estimated to be about 40 million light years from Earth. It is perhaps 130,000 light years in diameter, somewhat more than our Milky Way galaxy.

Technical Information:

LRGB: 150:30:30:50 (All 10 minute subexposures; L unbinned; RGB binned 2x2).

Equipment: 10" LX200 at f/4.6, and an SBIG ST-7E camera/CFW-8 color filter wheel

Image Acquisition/Camera Control: CCDSoft V5.

Processing: All images calibrated (darks and dawn flats) and registered in AIP4WIN. Images average combined in CCDSoft. Five iterations of Richardson-Lucy (high frequency only) applied in AIP4WIN. Color combine, gradient removal, and many careful adjustments of curves and levels performed, and slight gaussian blur applied, in Photoshop 6.0.

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

Date: All images taken during the night of 7/20/02.

CCD Temperature: -15C

Moon Phase: Approximately a first quarter moon.

Copyright Mark de Regt, 2002