Autotracking subjects?

[Squidy]

Hi all,

I recently purchased the 5Ds and love it. However i'm having trouble with autotracking subjects. I went to a bird show and when the birds were on the handler's hands it was fine, but when it took to flight to the other handler the bird became a big blur and out of focus. I was shooting at 1/2000s so I know it wasn't shutter speed.

How do I correctly track subjects? I had the impression I'd see the focus point follow the bird but this didn't happen at all

[NFLD Stephen]

Just a couple quick things to check: I assume you are in AI Servo mode for AF? What AF point selection are you using? Using the automatic AF point selection will enable the focus to track across all AF points, while using zone AF will only track across the points in that zone. So if you are having trouble keeping the bird in the frame, you may want to use the full point spread with automatic AF point selection. There are also a number of AF settings which can be changed in the AF menu (ie sensitivity, tracking rates, point switching, etc). The camera manual is a good starting point to read if you think any of those items need tweaking. Personally, I leave most of those menu AF settings unchanged on my 5d3. You might also check the shot priority in the AF menu (2nd menus page I believe). Make sure you have the focus set as priority rather than the shutter speed (or release timing for the first shot) since generally having proper focus is more important than proper timing.

Stephen

[peety3]

Good points above by NFLD Stephen. I break it down into several "dimensions" of AF settings. Obvious is One Shot vs. AI Servo, and you know you want AI Servo. Next is how do you want to use your points, and there are six choices in progressive order: single/spot, single, single"+"4 (arranged in a +), single+8 (arranged in a box), zone, auto-tracking. Now, here's where it gets a little tricky: at the bottom of page 93 in the manual, you'll see a reference to a menu item that changes the starting behavior of autotracking. If the menu item is disabled, I believe you have to start your tracking from the center point. If the menu item is enabled, I believe you can choose your starting point from any one of the points, so you could start with an off-center composition and then follow the subject within the space covered by the AF sensor (remember that with FF it's always physically limited to 1/3 the height of the scene). After that, you've got the Cases for how to optimize the tracking. There are technically 75 possible combinations, but Canon pre-selected 6 of them as Case 1-6. I flip-flop between Case 2 (for sticking to ONE subject) and Case 3 (for staying on the leader whoever that is at a given moment), but YMMV. Further, there are menu items for how to tune other prioritization and behaviors.

One other note: I can't keep track of which cameras do what, but some of them don't show you ANY of the AF tracking squares if doing auto-tracking in AI Servo. Your best bet may end up being to enable display of the selected AF point(s) in the LCD review/chimp screen, and slowly learning the behavior of your camera by reviewing your work.

[Squidy]

Thanks peeps, greatly appreciated

[DavidEccleston]

According to the review of the 1DX mark II, over on LensRentals, you'll want one for improved tracking performance.

But, more seriously, I find that tracking works better at telephoto distances. It's for the same reason lenses have focus limiters, it takes more rotation and time to adjust focus by a foot when something is near the camera, then it does when it's half a field away. For subjects moving at you, you'll track until you get to the point where the lens just can't keep up anymore.

What I found funny about the LensRentals 1DX mark II review was that they said they were making it extra hard on the 1DX by using a long telephoto lens. To me, that makes things *easier* for the camera, as long as you can keep the subject under the focus point.