one of my greatest pleasures as a young person was sneaking into the boneyard at Davis Monthan AFB...first naked woman I saw was on the nose of a B-17...
My grandfather designed the first "cushioned" bucking bars that were used when riveting aircraft together during manufacturing. The rivet person would use the gun on one side while another person used the bucking bar on the other and his design cushioned the vibration making it much more comfortable for the bucking bar holder. The pieces he designed covered all possible shapes they may need to build the aircraft. He was also one of the first pilots to ever fly into the Oshkosh airport for the fly in that has become an annual event. My son even taught a class in maintaining the new "Sports" class of aircraft in the EAA building. Only one of 3 authorized by the FAA to teach it at the time. My grandfather's bucking bars are in that EAA museum. Here's a pic of the display.
Nokta FoRs Gold, a Gold Cube, 2 Keene Sluices and Lord only knows how many pans....not to mention a load of other gear my wife still doesn't know about!
Gotta ask though...why shoot aerial shots on a nice day with the lens
stopped all the way down to f20?
No doubt you had your reasons, but if taking those types of shots is
something new to you, dropping the ISO down to ISO 400 (or lower),
and then opening the aperture up to f4.0 (or your lowest setting)
would give you a much, much faster shutter speed, and the images
would be quite a bit crisper/sharper.
I used to practice on flying birds for a week before the annual airshow,
as that got me tuned up for holding focus and taking multi-burst shots
while looking up and following the bird/plane.
Also appears you've got several dust bunnies on the cameras sensor. If you
don't have the experience and proper materials to clean the cameras sensor,
then most quality camera shops can do it for a very low cost. Even when I
was shooting professionally I still took my cameras into the shop for cleaning
the "mirror box" and sensor, as if not done right you can severely damage
a sensor..making the camera pretty much useless until it's replaced (and they're
$$$spendy$$$).
Can't take those types of shots anymore, as if I look "up" there's a strong
chance of me going right over on my arse, or worse yet to one side or the
other. Might be able to have a go at it if I was sitting down, but still not sure
I could look through the viewfinder while looking up and not get uber-dizzy
in the process.
Here's a seagull shot from a couple years back...talk about being in the
"Danger Zone"!
1/500s, ƒ/8, manual control
ISO 320, Focal Length 300 mm, manual exposure
White Balance = auto (0)