ONE SHOT, AI FOCUS and AI SERVO

Kryptix

Kryptix

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Can someone please explain what these do exactly? I'm pretty sure it's different ways to focus but can someone explain why I should use them?

I've had a quick search but I can only find people saying which you should use on certain shots.
 
I'm gonna attempt, although I stand to be corrected

One shot is a shooting mode, which means the camera will take one shot when you press the shutter release. As opposed to continous, which will give a continous burst of shots.

AI focus I think is Canons name for 'intelligent' focusing, it will try to focus on either the closest object, or the what it thinks is the subject you are shooting when you half depress the shutter You could reframe if you wanted to while keeping focus locked. (i.e the camera chooses the focus points)

AL Servo. do you mean AI Servo? I believe this is the canon name for the type of focusing that will track a moving object, say you have a car coming towards you, you can focus onto the car when it is far away by half depressing the shutter release, and asthe car comes nearer the focus motor will adjust to keep the car in focus. In the mode you often get 2 priorty options - shutter priority and focus priority, the former the camera will fire the shutter whenever you depress the button all the way regardless of focus, the latter the camera will only shoot if the subject has focus.
 
It's all explained in your manual. AI focusing modes are continuous, the camera will keep adjusting the focus to track a moving subject, as long as you keep the button pressed.

I forget the differences between AI Focus, and AI Servo, I think one is supposed to be smarter and detect when the target stops moving.

One shot focuses once, then thats it, until you release the button and press it again.

I shoot in servo mode all the time, continuous focusing when I need it, and it's not hard to just let go of the button when I want to stop tracking. This is with focus moved to the back button as opposed to the shutter release.
 
Thank you both for your help, but what do you mean by this?

Jayst84 said:
This is with focus moved to the back button as opposed to the shutter release.
Click to expand...
 
it means you can assign a different button with the * on it. This is on the rear of the camera near where you thumb would go. It leaves the shutter release button with one function only.
 
How do you do that?
 
Kryptix said:
How do you do that?
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As Jay mentioned, all is explained in a very clear and highly descriptive manner in the user manual.

I'm not trying to cop you out here mate, encouraging folk to read their camera manual when found asking questions such as the above is a positive thing. Trust me. :thumbs:
 
And also search the TP forum; you can be certain that someone has asked the question before you and, certainly with regard to back button focusing (using the * button) you'll find loads of info. I always try searching before asking :)

HTH

Cathy
 
AI Focus is supposed to intelligently detect whether the target is moving or not, and then select either a One Shot AF or AI Servo mode. I tried it once, but I couldn't get on with it, and now manually select either One Shot or AI Servo depending on what I'm trying to shoot.
 
jaffamuffin said:
One shot is a shooting mode, which means the camera will take one shot when you press the shutter release. As opposed to continous, which will give a continous burst of shots.
Click to expand...

One shot is where the camera focuses and holds the focus at that point, so not ideal for moving objects
 
basicly, one shot for still objects, AI focus for moving and servo for objects that are going to move.
 
Kryptix - you now have a reason to unwrap the manual ;)
 
One shot - for still subjects - select what you want to be in focus, press shutter half way, keep it held and recompose shot. The original subject will remain in focus.

Al servo - for moving subjects- press and hold shutter half down, while you do this the camera will keep refocusing as the subject moves.(very simple description - see manual for specifics)

Al focus - combination of two above - camera will automatically switch from one-shot to to al servo if the subject starts moving

Anna
 
Cheers people... :)
 
annao said:
One shot - for still subjects - select what you want to be in focus, press shutter half way, keep it held and recompose shot. The original subject will remain in focus.

Al servo - for moving subjects- press and hold shutter half down, while you do this the camera will keep refocusing as the subject moves.(very simple description - see manual for specifics)

Al focus - combination of two above - camera will automatically switch from one-shot to to al servo if the subject starts moving
Anna
Click to expand...

Whilst, in theory, this is perfectly correct, but I've been led to believe in practice, it doesn't work particulary well and is best avoided. Can anybody else confirm this?

Pete
 
Pete Gl said:
Whilst, in theory, this is perfectly correct, but I've been led to believe in practice, it doesn't work particulary well and is best avoided. Can anybody else confirm this?

Pete
Click to expand...

I've found that to be true. Which is partly why I have focus on the back button.. Just let go when the thing stops moving, or something passes between you and the target.
 
Considering the 1D bodies do not have an AI focus mode, I would avoid it. I does not work. I have tried repeatedly and given up. If a 1D does not need it, neither do I!
 
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