NGC 7027

NGC7027.jpg (3423 Byte)

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Who ?

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SBIG ST7 E
6x10s, not guided
Pollux 0.8m azimutal mounted telescope
3557mm (=140 inch) f/4.44
3-lens Wynne corrector
1.75 arc seconds
Deconvolution with AIP and symmetrical Gaussian blur
half moon, everything wet
Philipp Keller

Between the M57 exposure and this exposure I collimated the prime-focus. You can see that the effect is dramatic.
I did this by defocusing a star and looked at it in the focus mode and made real-time adjustments to the primary mirror until the coma disappeard completely.
This method is much better than the collimation by eye because you have a better sensitivity. You need good seeing for the final collimation !

NGC7027_Hubble.jpg (5129 Byte)

This is a fantastic picture of the HST from this very small planetary. Please note that the size of this planetary is about 10 arc seconds only but you can see that the above details are all real since they can also be seen in the HST image.