What Autofocus setting do you use?

John Mc

Suspended / Banned
Messages
742
Name
John
Edit My Images
No
On my 500D theres 3 Auto focus settings. I have little knowledge of which to use and when, when im photographing Wildlife. After reading a little bit of info on Canons website, i think Ai Focus is the best to use as it switches depending on what i photographing(static or moving).

So i thought i'd ask you folk what setting you guys use? And is there a reason why you pic that one?
 
I use a 500d and it pretty much stays on One Shot for everything.I have tried A1 Servo for flight shots etc but get more success with One Shot for some reason.It could be down to the lens` (Sigma EX 50-500) autofocus system though.I have never heard anything good about using A1 Focus amongst fellow Wildlife togs to be honest so just stick to One Shot.
 
Hello John..

After reading a couple of recent threads about Back Button Focus I switched the function on the 500D.

As mentioned in these threads, you can have it set on AI Servo and holding the * button keeps the focus tracking (if that is the correct phrase). A single press of the * button also acts like a One Shot. So today I was trying to shoot my cousins Macaw in flight with Back Button Focus, AI Servo and Continous Shooting.

It does feel odd removing the focus function from the shutter button but two days in and I am already set on sticking with it. Its also useful when using my 10stopper because the focus is removed from the shutter it won't hunt (I always forget to go to Manual Focus:bang:)

If you want to try it on your 500D its Custom Function 10, Option 1.


Andy
 
Thanks Andy, I'll give it a trial. Seems like it would be weird tbh :/
 
Be aware that in AI servo mode that the camera will allow the shutter to fire before it achieves focus, so if you don't wait long enough for the camera to lock on, your first shot may be OOF. In One Shot mode, the shutter won't fire until the camera thinks it has achieved focus. The problem in this mode is that if you don't press the shutter as soon as focus is achieved, it stops tracking the subject so if it's moving you may still get an OOF shot.

You may find AI focus worth a try, that starts in one shot mode, so won't allow the shutter to fire until focus is achieved, and then will switch to AI servo if it detects that the subject moves.
 
Hello John..

After reading a couple of recent threads about Back Button Focus I switched the function on the 500D.

As mentioned in these threads, you can have it set on AI Servo and holding the * button keeps the focus tracking (if that is the correct phrase). A single press of the * button also acts like a One Shot. So today I was trying to shoot my cousins Macaw in flight with Back Button Focus, AI Servo and Continous Shooting.


Andy

I generally use this set up, & really like it, but if think that the subject will stay still I switch to "one shot", as I believe it's more accurate.

I've always read that AI Focus is quite poor. I think it's better to make your own decision based on the circumstances, rather than hope the camera will get it right for you.
 
Last edited:
Nothing wrong with AI Servo, you just need to understand how it works ;)

http://photonotes.org/other/ai-servo.html

Now, that article is a little old, but on XXXD/XXD cameras AI servo still works on release priority. In other words for the first frame it's designed to shoot as soon as you fully press the button regardless of whether or not the subject is in focus.

On the 7D and I think the 1D, you can change that though a CF to focus priority instead. All other cameras are still release priority.

(That site contains an excellent EOS flash description too!)
 
Subject isn't moving - One Shot
Subject is moving - Servo

I'm not a fan of Al Focus (1 series doesn't have it) because I found in the past it didn't do what it was meant to do quickly enough. All it does is change from One Shot to Al Servo if the subject moves. I found it did this but too slowly for my liking.

Neil
 
AI Servo for me if it's for tracking birds in flight - centre point active with the 13 surrounding AF points activated to assist.
 
AI servo and back button focussing for me, That way you have AI servo, pseudo one shot and full time manual all without having to change a thing - great for wildlife and especially birds. It would seem very weird to me to use the shutter button to focus nowadays.
BTW John I would avoid AI Focus at all cost, it is c##p - never heard anyone have a good word to say about it.
 
Last edited:
Used back button focus with centre point only for years, find it difficult to use a camera not set up that way.
AI Focus - Not had much experience of it but strikes me if you want the camera to focus asap why make the camera waste time and processing power working out if subject is moving or not when you can tell it beforehand.
AI Servo - Use a lot, mainly for moving but will use for not moving (using back button release) if no time to change back and forth. If i have time will change to one shot if still subject as my understanding is that AI Servo spends slightly less time focusing compared to one shot on the basis that it has to sample focus more often as subject is moving. If this is correct then one shot will be slightly more accurate taking extra time to obtain focus.
 
Thanks guys, you've definitely gave me something to think about. I have another question though. I've enabled back button focusing, and ive been having fun with that, but what do i set my Af too? do i leave it on servo,or do i change between servo and one shot when i want to either shot? soo far, i've found most of my shots being sharper then usual using this system, so its fair to say im happy using this.
 
Thanks guys, you've definitely gave me something to think about. I have another question though. I've enabled back button focusing, and ive been having fun with that, but what do i set my Af too? do i leave it on servo,or do i change between servo and one shot when i want to either shot? soo far, i've found most of my shots being sharper then usual using this system, so its fair to say im happy using this.
For birds I keep on AI Servo for most of the time even for stationary birds. What you need to do with birds that are not moving is to 'pump' the focus (focus on something else and then back again on the bird) and when you are on the bird just release the back button and shoot away - this is like a pseudo one shot. The beauty with this method is that you always have Servo available to grab a flyer that suddenly appears.
I have tested AI servo v one shot for stationary birds on numerous occasions and can find no difference in focus accuracy.
 
Last edited:
For birds I keep on AI Servo for most of the time even for stationary birds. What you need to do with birds that are not moving is to 'pump' the focus (focus on something else and then back again on the bird) and when you are on the bird just release the back button and shoot away - this is like a pseudo one shot. The beauty with this method is that you always have Servo available to grab a flyer that suddenly appears.
I have tested AI servo v one shot for stationary birds on numerous occasions and can find no difference in focus accuracy.

Thanks for clearing that up for me Roy, Im going to give this a try tomorrow weather permitting. Going to take a trip to my local Rspb centre and take a walk around for the day.
 
You can practice it just panning the camera around the house/garden. The servo will focus on objects as they 'move' in the frame whilst holding the back button or just tap the button once for a One Shot type focus.

If you need to change back its pretty easy using the 500D Shortcut buttons. I had a habit of scrolling through the main display to change things like AF and WB but have been using the Shortcut/scroll buttons surrounding the Set Button which is obviously quicker.

Its very likely to be my default shooting method.
 
Hi guys,

Went out today and tried using back button focusing. Found it strange for a little while, but once i got the hang of it, it seems to be a very good technique. One that I'll be using more and more.

Im using Ae/af,no ae lock, custom setting 3. I found this to be better then any of the others. I'd rather use something I'm comfortable with then something I'm not.

Anyway, after not getting much luck with the shots due to the length of my lens (70-200) I'm thinking of setting up a little feeding station in my garden until I can afford a longer lens. I think this will give me time to practice with back button focusing and my over all panning shot's (which I desperately need to work on).
 
Back
Top