How do you go about the practice?
Great question, and I’ll try answer without being too overly wordy (not easy for me

).
First and foremost, I try to think about bokeh, since most of my hummer shots are taken at 300-400mm FL at fairly close range. We have a variety of different backgrounds in the area (we’re next to a golf course) ranging from shrubbery to lawn to trees. I try to change my angle periodically to provide differing backgrounds and bokeh, which can make the shots more interesting.
I stick with AF because at that FL and distance, DOF is wicked thin, so I haven’t found preset focus to be all that accurate, since the birds often hit different parts of the feeder (I like your idea of taping off part of it). The 100-400 locks focus quickly so AF speed hasn’t been any sort of an issue. I shoot at widest possible aperture for thin DOF and try to tweak ISO to get exposures of 1/1000s or so, give or take. Allows for a little wing blur but it’s usually enough to freeze most, if not all of the action.
I get a ton of rejects and missed shots... it’s really hard not to with such a fast moving subject, and it requires a boatload of patience, which I’ve had to develop over the years. They don’t necessarily come more than once every 10 minutes or so and only stay for 10-20s max. So, you have to be at the ready at all times. Fortunately, my feeder is on a deck, so I can set up a chair, get comfortable, and wait for the little beauties to show up.
One option would be to shoot at a shorter FL and remotely operate the camera, as you do. It would increase the possibility of getting the shot (a bit more DOF and wider FOV) but would require more cropping. I might try that and see whether I’m as happy with the results. Good to compare notes. Always something to learn here.
--
Jerry-Astro
Fujifilm X Forum Co-Mod