Sun - with Sunspot 917
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I took my brand new solar filter out for a spin the day after it arrived. I got relatively lucky - it being solar minimum so there are hardly any sunspots on the Sun's disk - since there was a decnet-sized sunspot group. I shrunk down the image of the uninteresting disk but I provided an inset of the full-size image of the sunspot group.
One thing you might notice is that the edge of the Sun appears to be darker with a pretty obvious gradient from the middle outward. This is called "limb darkening" and it is due to the fact that the Sun is a big ball of gas.
| Object | Sun with Sunspot Group 917 |
| Common Name | Sun |
| Date, Time, & Moon | October 21, 2006; N/A |
| Location | Westminster, CO |
| Optics | 1000 mm lens; f/16 |
| Camera | Canon Digital Rebel 350D XT |
| Exposure Details | 5 stacked 1/200 sec exposures; ISO 100 |
| Optical Correction | No Dark- nor Flatframe-Correction |
| Camera Position | Normal camera operation. |
| Guiding | None |
| Processing Details | PhotoShop CS - Averaging and Levels/Curves adjustment |
| Image Size | Sun is 30 arcmin in diameter |
| Magnitude Depth | Sun is magnitude -26.5 as seen from Earth |
| Notes | First image taken with my 72 mm solar filter for my 1000 mm lens. |