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Powermates for deepsky?

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Since buying my scope a month ago i haven't seen one clear sky grrrr. I dashed out once when i saw a gap in the clouds to test it with my new cam, and after some serious photo shopping to get rid of massive CA, my shot of the moon is impressive (to me)

My next target will be the whirlpool galaxy, autoguiding etc etc. I know its going to image alot smaller even at 18mp. The occular plugin on stellarium seems to be spot on in regards to what to expect.

If i wanted to achieve some extra magnification could i use a powermate/dslr with success on deepsky objects? and at what power would i have to draw a line? I'm currently using a st150 refractor. Is the only issue a longer exposure time? or would there be serious image degradation at the extra magnifications? Ill be upgrading scope sooner or later so the powermate with be handy whatever i do.

So to conclude, i am just wondering if its worth buying one, and what power to buy. I'm only interested in imaging deepsky.

Thanks all.



    Brown Dwarf

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I think this should be in the imaging sub-forum, however it's been covered before - the short story is that you will get some coma introduced.


If you look at my post there's some input about calculating additional time and dawes limit.

Edited by NickK, 07 May 2012 - 07:25 AM.

Vixen A80MF DIY Helio-spectrascope | Pentax 105SDP | EQ6 Synscan | ATIK 16ic, Titian, 383L+, OAG, EFW2 | Baader LRGB | BH 3.5, 13, 31mm | TV 2x & 5x PM, 20mm Plossl | Aurora Panel | Unhinged Mac developer for AOSX & Author of ATIK's OSX Drivers (R1.30 13-May)



    Geek !

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Moved to imaging ..........
Skywatcher Explorer 130 PDS & Skymax 127, EQ3-2 mount, Canon 7D DSLR

Rare female aviation geek, often found near Coningsby




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Thanks and sorry for placing it in the wrong section. I was reading coma is less of a problem with refractors? Mine isnt a very good scope though lol.

I think ill just try and see, using max 2x ;) TY.


After more reading...

I have a 550d so my sensor diagonal measurement is 28mm. Scope focal length is 750mm

750 / 28mm = 27x magnification prime focus? Maximum useful magnification in perfect circumstances is 300x So i have plenty of headroom? longer exposure and coma are my main problems?

This optical stuff baffles me, the maths is easy, its just not intuitive lol.

Edited by danielbb, 07 May 2012 - 05:36 PM.

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