What settings do you use for in flight tracking? I know you use Canon so the settings will vary somewhat, but I was have some issues on the Farne Islands. The very flat light didn't help, however my D300+Sigma 300mm f2.8 had some issues with achieving focus lock and keeping the lock. I had most success with AF-C and 21 dynamic points, but it was still erratic. Any tips or suggestions?
The MkIII has so many complex af adjustment settings, I've messed around with all of them, I have no idea whether they exist on the D300 or if they do what they're called but i'll list the important ones for you.
I mainly use 2 modes of focussing for birds in flight, the one I use the most is centre point with surrounding assist, this consists of a single point of focus with each point next to it acting as an assistant, so it kind of looks like the figure of 5 on the side of a dice, with the middle point being the main one.
I turn this off if I need absolute precision and just the centre point without any interference (shooting through a bush or grass)
The other mode I use is "ring of fire" where all the points are activated, I use this to pickup birds which move around all over the place, where its impossible to keep a centrepoint pinned on anything, the razorbill shot in this post was taken like this as they're all over the place in the wind.
Trouble with this mode is that the focus points will latch onto the main body of the bird and render the head oof, if it has a long neck like a gannet/swan/goose, if you shoot at F5 or wider.
"AF Tracking sensitivity"
If you're tracking something moving, for example a car coming towards you and you move the camera away from the car to the background, this setting controls the amount of time the camera will take before it focusses to the background if you don't move it back on the car quickly enough, say if the car turned a corner real fast and you lose it in the viewfinder for a second, if you had it turned right up you'd focus to the background making it difficult to get back to the car again.
I have this setting turned right down, if I move off one thing onto something else in flight, i'll re-pump the shutter to force the camera to learn the new subject. If you lose a bird in flight its very difficult to get it back in focus.
"lens drive when AF impossible"
Basically if the camera feels whatever it is your pointing at can't focus, it sends the lens through its focussing range once again as opposed to just stopping. I have this turned on.
"AF tracking method"
Basically means that if you're following something, and something gets in the way, the camera will or will not focus to the new object, I have this turned off so it ignores the foreign object and keeps on the main subject, for example a car going past lampposts which keep interupting the focus.
"AI servo 1st/2nd priority"
Basically means that the camera will either dedicate itself to producing high speed shooting (10fps) or ditching the drive speed and concentrating on AF tracking, so when a bird is moving all over the place, the camera might only let me have 3-4fps at the expense of making sure the subject remains in focus. Normally happens if something turned towards you or away from you very quickly and the camera needs a moment or 2.
"AF point display during focus"
I always have the selected focus point lit up in the viewfinder when doing birds in flight, just to act like a crosshair, I used to do lots of clay pigeon shooting so this sort of thing is natural to me, others prefer it switched off.
I also make a lot of use of the focus limiter switches on my lens, I don't know if the sigma has them, but it basically limits the focussing distance.
For example my 300 F2.8 has 3 settings.
2.5 meters - infinity (the entire range)
2.5 meters - 6.4 meters (close subjects)
6.4 meters - infinity (stuff which never comes close)
This takes a load off the camera as it doesn't need to search through its entire range when you know the object your shooting will always be at a specific distance.
Last week with the Gannets coming around the headland, it was 20 meters away so I had the focus limiter set to 16meters - infinity to catch them quickly as they appeared.
As for general settings, I like to shoot as wide as possible, to get complex backgrounds into a sea of colour and to keep the shutter speeds up, hopefully over 1/640th, unless i'm trying to do arty 1/30th sec pictures. Also, a lot of the time I shoot in single shot mode or 3fps, for the simple reason that you can see what you're taking, 10fps is great as you can capture all different wing positions and poses, but you tend to lose sight of the subject and end up filling your flash cards with pictures that all look the same, plus with the viewfinder rattling around and flashing you pretty much throw composition out of the window.
Other than that, i'd say keep nailing them, not many people use the fancy AF settings on any camera, most people use centre point in some form or another as its the most trustworthy... I do quite a lot of flight stuff, and I do spend quite a bit of time practising on seaguls, some people think that £3k cameras are just p&s at moving targets but it really does take some and practise, i'd say i've spent almost as much time going through the manual on my camera (the pages are falling out, its that worn) as I have shooting birds in flight.
If you go on the FM forums or somewhere similar, there are always people posting their focussing settings up for different cameras, it'd be worth asking on there for advice on specific settings.
Although I post some of my best flight shots on here and places like FM, I do shoot a lot of junk in getting them, i'd say my in focus hit rate is about 50% for fast moving birds, probably 95% for stuff the size of ducks up to swan sized. I think Birds in flight is possibly the hardest test of any AF system you could find.
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