All Images Copyright Steve Cannistra

Please click here for a 45% size image.
Please click here for a 55% size image.

RA (J2000): 14h 3m 10s
Dec (J2000): 54 degrees 21' 45"
Position Angle (Pinpoint):  plus 0 degrees

M101 is a large, beautiful spiral galaxy in Ursa Major.  For visual observation, M101 is best seen using a low power eyepiece under dark skies.  Despite being relatively bright at magnitude 8.5, it has low surface brightest due to its large size.  There are many smaller, faint galaxies in this FOV.  More information about M101 may be found here.

Photographic Details:
Dates:  May 11, 13, 14, 2023.
Scope:  Takahashi FSQ106 at f5 on the Takahashi NJP Mount.
Autoguider:  ASI178 autoguider with SvBony 30mm guidescope, focal length 120mm.
Camera:  ZWO ASI294MM at -10C, with 7 position ZWO filter wheel.  Pixel size is 2.3 microns (Bin 1x1), yielding an image scale with the FSQ (530mm focal length) of 0.90 "/pixel (well matched for my seeing of  3 arcseconds).  Camera gain set to 50 (e-gain 2.13 electrons/ADU), offset 25. Read noise at this gain level was 2.18 electrons rms.
Baader LUM, R, G, B filters; 2 inch.
Image acquisition software:  MaximDL for camera control and autoguiding; CCD Commander for automation.
Exposures:  Total exposure 11 hours (LUM: 5 hours, 60 second subs; RGB 6 hours, 120 second subs).
Processing:  Calibration, registration, local normalization, cropping, dynamic background extraction, BlurXterminator, NoiseXterminator, and histogram transformation in Pixinsight; Subsequent LRGB processing in Photoshop.

Please note:  Graphics on this website may not be reproduced without author permission.

Back to Galaxies