M81 (January 2005)



This is a combination of two different capturing runs. The first was a single DSI frame centered on the galaxy core and reaching out to the edge of the galaxy. The second was a mosaic of two images that covered more of the sky around M81.


The biggest problem I had was matching up the different images to generate a seamless composite. In the end I had to resort to manual Photoshop methods to mask out different background areas and alter them to match the other images.

Ursa Major 9H 55m  69° 4'
Magnitude: 6.8
Size: 21' × 10'
Distance: 12 million light-years
Best Month: February


Source: SEDS

Meade 8" SN LXD75
Meade Deep Sky Imager
(no IR filter)

3 hours 55 minutes RGB
(200 × 30 second exposures
plus 192 × 42.4 second exposures)

18 – 21 January 2005
Cambridge, MA

See Also
M81 and M82