David's Astronomy Pages CCD Images - Session 74 (2004-11-13) Images (S73)   Images (Main)   Home Page   Images (S75)

Notes (S00074)

- Imaging session was with a focal reducer bringing 8" f/10 LX200 to f/7. 
- Images were recorded with ST7 CCD camera. Filter Wheel with CBVRI filters
- 1.5 hour session (thick high cloud developed after 1 hour - the remainder of the session was used for taking dark frames)

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NGC 6946 - Spiral Galaxy

NGC 6946 (Cygnus/Cepheus)

CCD Image 3 x 5min (average combine),  C Filter, Autoguided 2004-11-02 00:41 h UT (#74015-17)

Negative CCD Image Image Details as above, with square root brightness scaling, 1050-1500 ADU, Negative

False Colour CCD Image Image Details as above, with square root brightness scaling, 1050-1500 ADU, false colour.

False Colour CCD Image Image Details as above, with square root brightness scaling, 1050-1500 ADU, false colour.

False Colour CCD Image Image Details as above, with square root brightness scaling, 1050-1500 ADU, false colour.

CCD Image Image Details as above, with blur smoothing

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Magnitude Limit

Magnitude of +17.5 is reached in the 3x5min image of NGC 6946. (The black smears on right-hand side of image are patches of frozen condensation which developed on CCD sensor - indicating that the desiccator in the CCD camera has reached its limit and needs to be regenerated - an approximately 12 month maintenance task. Fortunately. the frost slugs didn't impact the imaging of the spiral galaxy)

CCD Image 3 x 5min (average combine),  C Filter, Autoguided 2004-11-02 00:41 h UT (#74015-17)

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