EOS 90D Switch between AI Servo and One Shot quickly by pressing one button?

[AdoNetok]

My camera is Canon 90D. Usually I set AF Operation as AI Servo. Is this the best setting for still objects? Someone suggested switching to One Shot. How to switch between  AI Servo and One Shot quickly by pressing only one button?

[Anonymous]

You could assign the depth of field preview button to switch between the AI servo and One shot focus modes. You will have to hold the button in to cause the switch between the two focus modes. In the Custom Function menu (Operation/Others Custom Controls) you can reassign the button functions. This is based on an 80D, but I would think you have similar options on a 90D.

That being said, I think One Shot focus is best for still objects.

[AdoNetok]

Yes, I got it. Thank you.

[AdoNetok]

I set up depth of field preview button to switch between the AI servo and One shot focus modes.

Here are the initial setting.

1) One Shot as AF Operation, 

2) AF-On (Back button) as AF start, 

3) Using left hand finger to press Depth of field preview button to change to AI Servo 

Question:

When pressing Depth of field preview button, can I release Back button and then full press shuttle button to take photo?

Please advise.

[Anonymous · Accepted solution]

Yes that should work. You will have to hold in the DOF preview button while taking the photo.

[AdoNetok]

I found that the * button is better than DFP button. I will update.

I use the AF-On back button to focus, I can move my thumb to press and hold the * button to change mode.

[AdoNetok]

After testing, DFP button is still the best because when you switch to AI-Servo and press Back Button to focus with the thumb, you need to hold it.
At this time there is no finger to press the "*" key.

[ebiggs1]

" I set AF Operation as AI Servo. Is this the best setting for still objects? Someone suggested switching to One Shot."

One Shot is best for stationary subjects. There is no good reason to be able to switch between AF modes for that.

It sounds like you are trying to make a simple job way more difficult than it is or needs to be. First reset the 90D back to factory default. Now set just One Shot mode.  I would also select and use just the center focus point and put it exactly on the part of your subject you want in perfect focus. You can now use your DOF button for exactly what it was designed for DOF. You don't need BBF for this work. Remember KISS.

[AdoNetok]

99% of the time I'm taking photos of birds, and even when the bird stops in one place, its body moves a little bit. So I tried many methods, still need to switch between the two AF. Please look at the night heron I took this morning.

 

[AdoNetok]

This green heron is throwing a tantrum, its feathers keep changing, I have to quickly switch to AI Servo mode to shoot it.