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CCD Images - Session 74 (2004-11-13)

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Images (S75)
 
CCD Session S00074
Bullet Notes from CCD Session
 
Bullet NGC 6946 Spiral Galaxy
Bullet Magnitude Limit

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)
Image
CCD Image
3 x 5min (average combine),  C Filter, Autoguided
2004-11-02 00:41 h UT (#74015-17)
 
Image
Negative CCD Image
Image Details as above, with square root brightness scaling, 1050-1500 ADU, Negative
 
Image
False Colour CCD Image
Image Details as above, with square root brightness scaling, 1050-1500 ADU, false colour.
 
Image
False Colour CCD Image
Image Details as above, with square root brightness scaling, 1050-1500 ADU, false colour.
 
Image
False Colour CCD Image
Image Details as above, with square root brightness scaling, 1050-1500 ADU, false colour.
 
Image
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)
Image
CCD Image
3 x 5min (average combine),  C Filter, Autoguided
2004-11-02 00:41 h UT (#74015-17)

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This Web Page: CCD Images - Session 74 (2004-11-13)
Last Updated : 2015-05-16
Site Owner : David Richards
Home Page : David's Astronomy Web Site