Globular Star Cluster Size Comparison
| Object |
Globular Star Cluster Size Comparison: NGC5139 (Omega Centauri), in Centaurus - 55 arc-seconds M13, in Hercules - 20 arc-seconds M92, in Hercules - 14 arc-seconds NGC1851, in Columba - 12 arc-seconds |
|
| Telescope (Photo) | Celestron 8" SCT OTA @ f/6.3 on Losmandy G11 Mount | |
| Telescope (Guiding) | Televue 85mm refractor @ f/5.6 on Losmandy G11 Mount | |
| Camera (Photo) | Canon 20Da DSLR | |
| Camera (Guiding) | Meade DSI Pro II w/PHD Guiding | |
| Exposure Detail | Each cluster: median combination of 20 images at 60 seconds each, ISO1600; RAW file conversion, full calibration (bias, flat, dark, and flat dark), and initial image processing using ImagesPlus 3.75; final image processing using Photoshop CS3 | |
| Location |
Private Property at
Chiefland Astronomy Village, Florida (N29.406, W82.860) |
|
| Date | 03/25/09 (NGC5139, M13, M92); 03/22/09 (NGC1851) | |
| Comments | All four clusters were taken with identical exposure sequences using identical optical instrumentation, and cropped/processed identically in order to make the comparison precise |