NGC 7635, Bubble Nebula, LRGB, 96% waning moon
Posted: Thu Sep 19, 2019 3:36 pm
A first serious attempt to get to grips with imaging using LRGB filters. The conditions were not ideal with NGC 7635 on one side of a tree and the moon on the other. LRGB colour balancing using ratios has been tested without wasting good conditions.
The RGB ratio used was 1.7 : 1 : 1.5. RGB was bin 2x2 with 60s exposures. L was bin 1x1 with 90s exposures. The ratios were derived based on the work done by Brian Morgan (@oopfan) at https://u235.herokuapp.com/#color-balance-instructions.
Celestron AVX mount, Vixen 81sd refractor, Altair 1.0x flattener. Atik 314E CCD camera.
Sharpcap 3.2 with Atik ASCOM drivers.
Unguided, focus with Bahtinov Mask, Teleskop LRGB filters & Teleskop filter drawer.
Integration time 2.2h; L bin 1x1 50x90s; RGB bin 2x2, 60s; RGB 24:14:22; 100 bias, 100 flats @ bin 1x1 & bin 2x2; 30 darks @ bin 1x1 & bin 2x2.
Imaging order was R > G > B > L for capture east of the meridian (L > B > G > R for west of the meridian).
Total captured data = 1.1Gb.
Calibration, registration, stacking and RGB Composition were carried out with Siril. Final (minimal) processing used Gimp.
It will be interesting to revisit this target when there is no moon. While I wait for that I may try for an SII-Ha-OIII capture.
Dave
The RGB ratio used was 1.7 : 1 : 1.5. RGB was bin 2x2 with 60s exposures. L was bin 1x1 with 90s exposures. The ratios were derived based on the work done by Brian Morgan (@oopfan) at https://u235.herokuapp.com/#color-balance-instructions.
Celestron AVX mount, Vixen 81sd refractor, Altair 1.0x flattener. Atik 314E CCD camera.
Sharpcap 3.2 with Atik ASCOM drivers.
Unguided, focus with Bahtinov Mask, Teleskop LRGB filters & Teleskop filter drawer.
Integration time 2.2h; L bin 1x1 50x90s; RGB bin 2x2, 60s; RGB 24:14:22; 100 bias, 100 flats @ bin 1x1 & bin 2x2; 30 darks @ bin 1x1 & bin 2x2.
Imaging order was R > G > B > L for capture east of the meridian (L > B > G > R for west of the meridian).
Total captured data = 1.1Gb.
Calibration, registration, stacking and RGB Composition were carried out with Siril. Final (minimal) processing used Gimp.
It will be interesting to revisit this target when there is no moon. While I wait for that I may try for an SII-Ha-OIII capture.
Dave