Shot using the 400, with 2x Quantaray extender, and with the 1.6 FOV crop, makes this about 1280mm. Yep, I used my tripod.
Autolevels, and resized.
Oh and here's the pre-levels shot... kinda hazy, and I don't have any filters for the new lens just yet.
Oh yeah. Shot in RAW... Adobe RGB.

