Wow, i must admit that for a moon shot, i never consider following the rules of third because i simply thought it wouldn't work. I would thought centered is the best way to present it. After trying it out in Lightroom, I think i kinda like it. Here it is
http://i105.photobucket.com/albums/m223/Jdmhoodz/IMG_2486-3-1.jpg
I used my Canon 70-200 f/4L along with the Canon 1.4x mark II teleconverter, coupled with the 1.6x crop factor for my Xsi.. i got a effective focal length of 448mm. This shot is made possible with help from my tripod ofc
The 70-200 f/4L is sharp as a tack, even with a TC attached.. i honestly couldn't see any image quality degradation. The moon shown in the original post was a 100% crop of the file, since even with the reach i had.. the moon only occupied a small portion of the frame.
Now time to drop the money on a telephoto lens since you got a wide angle and all
Oh nice xD I guess it could have something to do with the fact that my largest focal length is 135mm and that I need like a 150% crop to get my shot your size lol