NGC253 in the Sculptor constellation.
The picture shown here was taken from the Atacama desert in Chile with a 50cm diameter F/8 Ritchey-Chretien telescope (Astelco) and a SBIG ST11000 CCD camera mounted on an Astelco NTM500 equatorial mount. The complete acquisition (control of the mount, focuser, camera, pointing model, image quality analysis, pointing, guiding, auto-focusing, preprocessing of the images ...) and remote control of all this was done using the amazing (more than) 'all-in-one' Prism software. Total exposure time is 8h10 minutes through Clear, Red, Green and Blue filters. Image acquisition and pre-processing by Stéphane, color processing by Thierry.