topic Re: EOS 90D Switch between AI Servo and One Shot quickly by pressing one button? in EOS DSLR & Mirrorless Cameras

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

AdoNetok — Thu, 22 Jun 2023 15:50:26 GMT

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?

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

Anonymous — Thu, 22 Jun 2023 16:08:32 GMT

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.

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

AdoNetok — Fri, 23 Jun 2023 05:26:33 GMT

Yes, I got it. Thank you.

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

AdoNetok — Fri, 23 Jun 2023 15:27:28 GMT

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.

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

Anonymous — Fri, 23 Jun 2023 16:07:17 GMT

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

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

ebiggs1 — Fri, 23 Jun 2023 16:14:06 GMT

" 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.

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

AdoNetok — Fri, 23 Jun 2023 18:28:05 GMT

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.

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

AdoNetok — Fri, 23 Jun 2023 18:35:45 GMT

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

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

AdoNetok — Sat, 24 Jun 2023 10:59:17 GMT

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.

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

ebiggs1 — Sat, 24 Jun 2023 14:39:48 GMT

" I have to quickly switch to AI Servo"

No you don't. That is not what Ai-servo is designed for. Your two bird shot are good One shot examples. Ai-servo is designed for a constant motion like a race car going in a horizontal motion across the frame. It is not for flickering feathers!.

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

AdoNetok — Sat, 24 Jun 2023 15:39:18 GMT

Thank you. I will keep on testing. Question

What should I use if the bird is on the branch but keeps shaking its head and tail? Still use One Shot?

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

ebiggs1 — Sat, 24 Jun 2023 16:02:24 GMT

"Still use One Shot?"

Yes, that is not an Ai-servo situation. 90% of all photos are best with One shot.

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

Anonymous — Sat, 24 Jun 2023 16:52:38 GMT

Unless the bird is moving towards or away from you, one-shot focus is best.

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

AdoNetok — Sat, 24 Jun 2023 17:00:22 GMT

Thank all of you, I completely understood now.

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

AdoNetok — Mon, 26 Jun 2023 08:19:38 GMT

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.

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

amfoto1 — Mon, 26 Jun 2023 20:06:26 GMT

A MUCH EASIER solution would be to use Back Button Focusing (BBF), which allows you to leave the camera in AI Servo nearly all the time. With BBF you're in full control of when the AF system operates and when it doesn't. You can start it up and acquire focus continuously, tracking an active/moving subject through the viewfinder and tripping the shutter when you want to grab a shot or take a short burst. Or, if you want to focus and recompose, use the AF On button to acquire focus where you want it, then lift off the button to stop AF, recompose and take your shot. You also can use a button on, button off, button back on technique to "dodge" obstruction that come between you and the subject while panning.

Another benefit of using AI Servo is that many modern zooms are varifocal or partly varifocal, meaning they don't maintain focus when zoomed. When you use One Shot with these, any time you change the focal length you have to consciously refocus the lens (doesn't matter whether you're using BBF or not... you still must lift off the button, then reapply it to refocus). However, if you are in AI Servo (possible thanks to BBF), the AF system will instantly and automatically correct for any loss of focus when a zoom is varifocal.

A minor drawback of using AI Servo all the time is that AF "confirmation" doesn't work in that mode. It actually makes sense, since in AI Servo the focus is continuous and never "locks", so there's nothing to "confirm" with the green LED or the "beep" (if you have it enabled). I don't know about 90D, but my 7D Mark II's display "AF" on the focus screen any time the AF is active. While that's not quite a "confirmation" that focus has been achieved, it does let me know AF is active. (As a side note: I enable the "beep" on my cameras. Since it only works in One Shot mode, this serves to remind me if I'm in that focus mode when I pick up one of my cameras and start shooting. Helps me avoid using the "wrong mode" with active, moving subjects. When I'm shooting sporting events, it's not uncommon for me to hear other people's cameras "beeping" at them... and I know that a high percentage of their shots will miss focus.)

With BBF, I hardly ever need to use One Shot. I shoot a lot of sports and some wildlife, leaving the camera in AI Servo and using BBF 99.5% or more of the time. Been doing that with my SLRs and DSLRs for at least 20 years. About the only time I switch to One Shot is when shooting a posed portrait, a macro/close-up or landscape/architecture. I shoot those a lot less, and don't always change modes anyway, so some of my cameras probably haven't been out of AI Servo in months... maybe even years.

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
FLICKR

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

AdoNetok — Mon, 26 Jun 2023 22:17:11 GMT

Thanks for giving me this knowledge. I will study it carefully and experiment with it.

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

ebiggs1 — Tue, 27 Jun 2023 14:22:01 GMT

The samples you displayed does not require you to go to the in-depth settings as described above. It is simply not necessary. Simple full time One shot and center focus point is not only much simpler but is actually better.

If you are still wanting to use a continuous AF mode you can try eye-face detection. I don't remember if the 90D has animal eye detection or not. I suspect it does not but maybe.