Quote:
Originally Posted by Jeffkop
.. So this must be a consuming task comparing all your images over time looking for little white dots that are not in another picture ... this must take ages to do ... or is there a PC automation that can do this ????
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Hi Jeff,
There is no real easy way around Supernova Searching for the amateur astronomer, you can however throw lots of $ at it. Technology has helped tremendously but the time factor (imaging and then checking) is still the issue.
The basic ingredients - Numbers and having good reference images to start with, preferably ones you have taken with the same equipment, comparing apples with apples. Using the Digitised Sky Survey Images (Red and Infrared) to check suspects against is also a must.
In my case I check each image "live" on the screen to previously captured images on another screen, while it slows my numbers down I am hoping that this will buy me time over those who use say Maxim Dls SN Blink programme to later check or the more well equipped ie CHASE (Chilean Automated Supernova Search) who use image subtraction.
You also have POSS (Puckett Observatory Supernova Search) who have multiple contributors to check the many captured images.
So really there is no substitute for (visual or ccd) - Numbers, numbers, numbers.
Many who do automated capture searches throughout the night rarely check their images on the go (they are usually asleep) so at some stage (next day - asap) they will blink several hundred images, can take hours.
In Stu Parkers case this has proved very productive, but has also missed a few (it can get very eye straining). In my case I am limited to say 150 images per night (I usually call it quits at midnight) and close the observatory. But I have checked those images and am now very confident I haven't missed any. I do now blink the galaxies that have lots of (foreground) stars around them (ie NGC4945). However I did miss one last July (wasn't blinking then) in another galaxy that had quite a few foreground stars around it, I largely put that down to tiredness.
My discovery rate is about 1 per 6000 images to date, so I would be happy with 1-2 discoveries per year from here on. I think POSS were at about 1 in 8,000 images and Stu comes in at close to 1 (I think) around 1500 images. CHASE have heaps of discoveries, they are semi-professional but I will be more than surprised if it were better than 1 in 6000.
Oh PS, Rob, why not send your fine image to Dave Bishop for inclusion in the SN archives. See link below.
http://www.rochesterastronomy.org/snimages/
Hope that helps.
Peter