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.