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ST-9XE Ad Edge 8 Combo?

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#1 John Miele

John Miele

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Posted 22 November 2012 - 05:01 PM

Hi All,

I'm interested in doing some photometry and astrometry with my Edge 8 scope. Was thinking the ST-9XE might be a good combo. With it s 20 micron pixels I get an image scale of 2 arc-sec/pixel @ f/10 and a FOV = 17'. The built in guide chip should be a big help too. Was wondering if anyone else was using this combo and what you all might think about it> I am assuimng the ST-9XE is a NABG chip? Cany anyone confirm that?



#2 gavinm


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Posted 22 November 2012 - 07:50 PM

The ST9 is NABG. In my opinion, the ST9 is a small chip with large pixels, suited for long focal lengths. At ST7 will give roughly the same FOV if you use a reducer but with a smaller pixel scale. 2' is pretty big, but I don't know your seeing conditions.

#3 John Miele

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Posted 22 November 2012 - 08:24 PM

Yea, I was just starting to think maybe 2 arc-sec/pixel would be too big. I could go with a ST-402ME which gives me a 0.93 arc-sec/pixel scale @ f/10. I need to plan for f/10 because right now there is no reducer for the edge 8 scope.

#4 *skyguy*



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Posted 23 November 2012 - 12:14 PM

Hi John,

I've been doing astrometry and photometry with my 12" LX200 and ST9-E camera for many years with great results. The scope uses a f/6.3 focal reducer (F.L.= 1920mm.) and with the ST9-E has an imaging scale of 2.19 arc-sec/pixel ... which is very close to recommended 2 arc-sec/pixel for astrometry. The camera's relatively large imaging chip provides a 19' FOV which is very important in maximizing the available number of comparison field stars for both astrometry and photometry. Also, the the NABG ST-9 cameras have a Full-Well Capacity of 150,000 e- ... one of largest available ... which will allow longer exposures before saturating, resulting in the "blooming" of the brighter field stars.

That said, I would think the ST9-XE on the Edge 8 (f/10) and would be ... arguably ... the perfect combination for astrometry and photometry.


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