M109 again, with the C11. With the ASI183mm

This is such a nice galaxy! Spiral arms and a central bar, beautiful! After the attempt to image it th elast nights with the C11 & Nikon, again a few nights (nights are short!!) now with the ASI183mm.

Th epixels are a bit small, and the C11 ‘s output is oversampled. In that respect the Nikon’s larger pixels (5µ) make more sense. However, this really worked out more acceptable then the previous attempts.

Using SIMBAD, you can identify some of the smallest and faintest patches in this image. SDSS J115703.88+532414.6 was about the faintest one with a listed green band magnitude of 20,893! The image itself measure 20′ x13′ end has a resolution of 0,6″ per pixel. Seeing was rather bad these nights, with nortwest sea air blowing over. Very clear however, with SQM 20,40 on average.

The C11 was guided with a 8×50 finderscope, using an ASI290MM. Autofocus was done using an Esatto 2″ focuser.

M109 3,8 hours LRGB C11 ASI183 Meldert May 2020
Searching the limiting magnitude
Astrometry from nova.astrometry.net