I don't know what was worse:


the IQ i got from 2x 2x teleconverters that seem to love purple, mounted on an already not-the-best lens,


or the thought of my neighbours ringing the cops because i was
pointing a big, black, bazooka-looking thing in the vicinity of the city
centre:


[img]/photography_gear1/resized-image.ashx/__size/1200x0/__key/CommunityServer-Discussions-Components-Files/8/7608.P7112335s.JPG[/img]


.


at any rate, the farthest focussing i got was about 3-500m, even at
f/5.6 * 4 (f/21.6) my DOF was only a few meters, the branches behind
were OOF. (and the weird things at the top of the photo were a
palm-thing across the road from me, maybe 30-50m away.) the branch at
lower left seems to be the best in focus, best you can get with that
setup at ISO3200 on a 7D at any rate.


[img]/photography_gear1/resized-image.ashx/__size/1200x0/__key/CommunityServer-Discussions-Components-Files/8/7416.IMG_5F00_5958s.JPG[/img]






your mileage may vary, anyone got an 800mmL or a 1200mmL? (there's one on ebay now, only US$80000, who wants to buy it to test?)