Object: Open cluster DO 12                      Constell: CAS

RA: 00h 40.8m           Decl: +60° 51'          Epoch: 2000
Mag:                    Size: 18'               Type: IV 2 p
Observer: Jere Kahanpää
Obs. place: Helsinki, Finland
Date/Time: 10./11.10.1996, 21.55

Telescope: C 200/2000
Magn: 160x              Filter:
Field: 19'              NE Lim.mag: 5.4m
Background sky: 4       Seeing: 2-3
Weather: +5 °C, no Moon.           

Brightness: 3           Alt: 70°
Description: The cluster should fill the field. and should be
centered on the brightest star of the northern group. 

The northern group (in the middle of the field): About 15 stars
with a large range of magnitudes. Scattered but clearly
detached. Stars mag. 10... Diam. 7'.

The southern group (near the SW edge of the field): A bit
fainter than the main group. Most stars mag 12 and a few fainter
ones. Triangular outline. A dozen stars within 6'. 

I think Do 12 includes (and is) these two groups which are
probably asterisms. Quite a nice field though.