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IC1805 and IC1848

Started by RobertM, Nov 02, 2009, 22:57:23

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RobertM

Yes but if I used f/6.4 a lot of the dynamic range would have been wasted due to the low signal and of course read noise might have been an issue.  Also 200mm f/6.4 = a 31mm objective = 40mm of wasted aperture and expensive glass.

7nm filters aren't extreme, I would have preferred 3nm but the costs were astronomic !

Robert

MarkS

No, I wasn't suggesting that you use F6.4 - I was just converting the background signal to units I'm more familiar with!

As you say, you should always use the fastest focal ratio possible to capture all the photons you can ...

Rocket Pooch

Hi Robert,

Not bad, if I had to be critical about the image I'd make the following observations.  The brighter stars look too which and there is a lot of noise in the image, so I'm assuming the DDP was a bit extreeme and thats why the white is very white, also a median filter could be a good move.

I do like the FOV and also the framing thats fab and the lens obviously performs.

Chris