Butterfly Nebula, second try

This narrow band color image is a combination of two channels, H-alpha = Red

O-III = Blue. Green channel is Synthesized from Red and Blue.
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Conditions were not too good last night, hard wind and clouds.

Guiding was really difficult doe the wind but PHD-guiding software does its best.

There was jus enough gaps between clouds, that I managed shot data for H-alpha

and O-III not enough though.

Actually part of the frames are shot trough not so thin clouds, maybe

H-alpha acts as a cloud filter : )

S-II data had to be left to the next time after the clouds rolled in.

Part of the NGC6888 the "Crescent Nebula" can be seen in the bottom of the image.

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Imaging data:

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Camera,

QHY8

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Filters,

Baader 7nm H-alpha and Baader 8,5nm O-III

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Optics,

Tokina AT-X 300mm @ f2.8

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Exposures,

5 X 1200s H-alpha

3 X 1200 O-III

+ flats and bias

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Guiding,

LX200 GPS 12" + PHD-guiding and Lodestar

H-alpha channel