M81-M82

(fritz kleinhans)


 

M81-M82:
April 17-18, 2012; Casitas, NM

TEC 140 mm, f7, AT2FF field Flattener, Canon Hutech 400D @ ISO 800, AP Mach1 mount, 50 mm f5 guide scope
Cropped, full resolution, 1.2 arcsec/pixel.

4 x 10 min subs = 40 minutes, 2 darks (not enough, lots of hot pixels)

M81 and M82 require different processing, this is the best compromise.  Individual processing of each galaxy can be found below.   I am not clever enough yet to recombine when done.


 

M81: (from above)
After discovering that Holmberg IX is close to M81 I reprocessed the above pic to bring out maximum faint detail in M81 (using Image Plus).  And there is Holmberg IX; the fuzzy patch below M81 -:)

Technical details as above; except these M81 pics are binned 2x2 yielding a resolution of 2.4 arcsec/pixel.

In addition to M81 and Holmberg IX, I count at least 11 additional galaxies in this pic. No doubt there are more but I got tired of looking.  See the labeled pic next below.  Based on the Sky Tools 3 chart, further below, I estimate that this pic goes to m = 19+.  Galaxies magnitudes are notoriously suspect for faint galaxies.  That said, galaxies to m = 19 are also visible.  I really need a two hour exposure now!


 

 

M81:  Labeled pic.


 

 

M81: Sky Tools 3 Chart

Stars to m = 19.


M82: (from above image)