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Old 04-03-2013, 09:31 PM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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Quote:
Originally Posted by PRejto View Post
Hi Ray,

Thanks for this interesting post. Like everywhere this is discussed nobody can ever agree!! But, I think Greg is right in the sense that as these cameras are used more and more certain facts will become clearer no doubt. I'm in no position to argue the technical side of things.....

I'm wondering if you might share which camera you decided to buy (and perhaps why), and which scope you intend to test this with?

I wonder how it might perform with my TEC140 at f7 (.95 arcsec/pix) compared with my KAF8300 (1.14 arcsec/pix)? Not a significant improvement in resolution, but would I see much improvement in sensitivity for RGB and Ha? Would it be worth the decreased FOV? Of course, as reported by several, the possibility to not need darks or deep cooling, and lighter package are all appealing selling points.

Thanks,

Peter
Hi Peter. Put the two options into the model. Looks like your scope would be a good match for either chip for hi res imaging down to about 2 arc sec seeing.
  • The 8300 will give you a much larger field of view.
  • The system broadband sensitivity will be about the same with either camera (the bigger pixels of the 8300 help with sensitivity, but lose resolution).
  • The 694 will have much better SNR (maybe 2x) at low signal levels in Ha narrow band due to the low noise of the 694.
  • The 694 will give you significantly better resolution (if you have a target that covers 100 pixels on the 8300, the 694 will put 140 pixels on it). that would be a noticeable advantage in good seeing
  • The 694 has a somewhat better dynamic range than the 8300, and the very low read noise of the 694 gives you more flexibility in exposure strategy.

Not sure if you want an opinion, but if it was me, I would push the 8300 as far as I could before deciding if I needed a replacement - but that is entirely your call, based on what you want to do. And of course you also need to consider the ancillary mechanical issues.

hope this is helpful. regards Ray

Last edited by Shiraz; 05-03-2013 at 11:00 AM.
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