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Old 02-04-2019, 10:07 AM
casstony
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Ngc 4945

I shot this galaxy in Centaurus last night, 25x3 min with the Edge 8 and 0.7 reducer.
I think dodgy stars are either from tilt in the T ring or a bad reducer.
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Old 02-04-2019, 05:35 PM
assbutt94
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Great effort Tony, the stars look fairly round

I could wiggle the camera on my Celestron T-ring a tiny bit.
If you are having the same issue, using a dust cap from the back of a lens as a template to make a gasket from a sheet of paper may help. Slipping it on the tring before you fit the camera will take some of the wobble out.
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Old 02-04-2019, 06:36 PM
casstony
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Thanks Nathan. I read about some of the early Edge 8" 0.7 reducers being faulty from poor manufacturing and exhibiting the same behaviour I've got, so the reducer is the prime suspect. Next time out I'll try without the reducer to see if that eliminates the problem.

I think I've got my tracking good enough for 2000mm - getting the atmosphere to cooperate is a little harder though.
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Old 04-04-2019, 12:08 PM
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Thats how a gallaxy should look..very natural to my eye. Well done Tony.
Alex
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Old 04-04-2019, 01:15 PM
Startrek (Martin)
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Tony
That’s a great image of NGC 4945 in Centaurus at magnitude 9
Do you think it’s tilt in your focuser accessories that’s causing the eggy shaped stars ?
They seem to be worse on the right hand side in off axis areas, might be tracking ?
Martin
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Old 04-04-2019, 01:46 PM
casstony
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Quote:
Originally Posted by xelasnave View Post
Thats how a gallaxy should look..very natural to my eye. Well done Tony.
Alex
Thanks Alex. Getting a stable atmosphere is the biggest issue for me at these focal lengths. The refractors do well under almost any conditions.
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Old 04-04-2019, 01:48 PM
casstony
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Martin, I think my tracking is good; it could be tilt or a bad reducer. I'll wait for the Jetstream to calm down before I can figure it out.
It is a nice, bright starburst galaxy.
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Old 04-04-2019, 09:01 PM
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Sunfish (Ray)
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Very good images in any case. Shows what can be done.
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