This is in semi-false Sloan colors, with i' -> red, r' -> green, g' -> blue. This gives a wider spectral range with no gaps.
The colors were calibrated using custom code and UCAC4 field stars with AMASS Sloan photometry. The color calibration was
deterministic and Photoshop CS6 was used only to apply levels. The result is consistent with a mostly red/orange cluster,
corresponding to a very old system.
Imaging Optics | Celestron EdgeHD 11 with reducer at f/7 |
Mount | Celestron CGE-Pro |
Guiding Software | MetaGuide with dithering from SGP |
Guiding Mode | Off-axis guiding with Hutech OAG5 |
Imaging Camera | Atik 383L+ |
Guiding Camera | QHY5l-ii |
Collimation | MetaGuide |
Focus | SGP and RoboFocus on the primary focuser - no mirror locks used |
Exposure Time | 3x15x2m |
Image Scale | 0.57" per pixel |
Raw FWHM | Down to 1.5" in subs |
Image Processing | Calibration and stack in custom software, only levels in Photoshop CS6 - no other processing |
Image Processing - Other | Colors calibrated with Sloan magnitudes using UCAC4 field stars and custom code |
Image Acquisition | SGP |
Other Software | PECTool, TheSkyX Pro for best guidestar selection with field of view indicator (FOVI) |
Other Hardware | Pyxis OAG Rotator for best guidestar, Telegizmos 365 cover, Long usb cable to outside setup |
Date | March 31, 2015 |
Filter | Astrodon Sloan i', r', g' |