Well, Canon 400mm f/2.8 will be awesome and with 2x teleconverter you get 800mm, or you can get the 800mm which is good enough I think
sorta off topic, but still Shuttle ops on Landing -
1st landing at Edwards AFB, Colombia, 1981, across the dry lake from the landing strip (on desert floor). I believe I rented a 400mm T-Mount, plus a 3x adapter (maybe 2x too - I'm checking with the friend who went along. Nikon Ftn. Transparency (forget which - it was a while ago and still have "search for those slides on my list".
Whatever I used only became good enough for good compHosition during final and on landing. I did get some useable, with cropping, of pass with wingmen and alignment turn. We were "only" 4-7 away or less across the lakebed. I don't know the distance you'll be (like at the "clock"), but if comparable, you can get some useable pics.
Anyway...
Many (many) years later> Canon 10D + 75-300mm IS (480mm 35mm equivalent) 1/1000, f/27 to f/9, depending on sky angle and sun and fudge factor. ISO 400, but a different DSLR (newer CANON could probably get away with 1/800) Gotta keep the f stopped down as much as possible, and need fastest shutter speed. I'm now remembering I had a 2x convertor mounted, too. Also, I did have IS, so might have be able to cut the shutter speed down. For this kind of work, though 400 ISO looks fine.
I shot SpaceShip One's first space flight, and was able to get a sharp enough image while they were at 40k' to recognize it and Whiteknight (planform easily discernible, even after they separated). On the ascent, it was a bit more than a dot, but could see some structure.
Have fun! I've seen an Atlas 1mile away, and others on ascent out of Vandenberg, CA - still great exhaust plume - can even see the shock diamonds sometimes, but we shoot from about 60 miles away, to the east. Just luck out on the flight path. We had hoped, years ago, for the west coast Shulttle launch facility to be used, but alas.
Again, enjoy. Wish I could get there someday, but don't think it's gonna happen. I'll enjoy vicariously! I'll be watching live, so if you make it out near the clock, where something MR or Apple like.
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