Quote:
Originally Posted by Pierre_C
Hi people.
Here is a photo from my very first session using a DSLR on a tracking mount last night – Jewel Box Cluster, NGC 4755.
I am pleased with the colours of the solitary red giant and scattered blue giants among the white stars.
There is a small amount of star trailing which I think is due to slight polar malignment.
I am looking forward to practicing on other objects.
Any thoughts on how to grow from here would be appreciated.
Thanks.
Equipment: - Celestron AZ102 refractor.
- Sky-Watcher equivalent EQ3 mount with dual axis motors and steel tripod.
- Nikon D7000 camera. 10s exposure. ISO 1600.
- NX Studio processing.
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Hi Pierre,
Great start.
A few suggestions: -
Trailing
Your main trailing is in declination indicating polar alignment error. That much trailing in a 10s exposure is more than a minor polar alignment error. If you are using an optical polar finder, you need to learn the polar star patterns. Once you learn the patterns, they are much better for optical polar alignment than the North hemisphere "Pole Star."
Focus
Your image is badly focussed. Use live view If your camera's live view is not sensitive enough for the stars in a particular subject, no problem. Just slew across to much brighter stars. You can try buying a Bahtinov mask and use live view. However if live view sensitivity is limiting you, a Bahtinov mask will make that more difficult. Make a mask with a few criss crossed pieces of string. This will transmit most of the light and you will see the diffraction lines from the stings.
keep up the good work
Joe