M51 Whirlpool Galaxy


Mark Stronge
  Comber, County Down
Photo Title
Date and Time taken
0100hrs GMT 21st May
Equipment used
Orion ED80mm, Vixen GP mount, Vibration isolation pads
Capturing device used
Canon 300D Digital Rebel digital SLR
Technical details
ISO1600, 13 frames of 30 seconds, stacked in Registax with final processing in PSP8

I was intending to image Comet NEAT again but some low cloud changed my mind to the meridian. M51 has been well placed for viewing and imaging for some time. Even though the skies do not get completely dark at this time of year, I found M51 fairly easily (for a change) and started capturing. It was fairly windy though the scope was quite sheltered. I wanted to take alot more frames, but the clouds came over and they didn't look like they were on a flying visit :-( This is my very first image of M51 and I'm fairly pleased with the result. A longer exposure is probably my next goal and higher magnification. This was a very wide field capture and I have only used the central area of the image.

Focusing was my main problem as looking through an optical viewfinder is quite dim compared with an eyepiece. Ideally, I could have gone to a bright star and focused on that and then gone back to M51 without changing focus but it was quite dim to find and would have been impossible to locate again without changing the focus when using an eyepiece. An off-axis guider would be ideal for this job. Instead, I took 20 second exposures and looked at the image at high magnification and adjusted the focus accordingly. This was a very slow method but worked well as I achieved a very fine focus on the dimmer stars.


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Last Updated : Friday, December 3, 2020

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