topic Re: Unless there’s motion, don’t use AI SERVO. in EOS DSLR & Mirrorless Cameras

Unless there’s motion, don’t use AI SERVO.

PajamaGuy — Mon, 09 May 2016 13:12:56 GMT

I’m sure the experts here already know this, so this is for those of us who aren’t experts.

Little League 10U when I’m sitting behind 2nd base with my 7D2 and 70-200 2.8 mounted on a monopod and shooting the batter at 10 fps I often get several frames (from the 2nd frame on) that are just slightly out of focus. Some are tack sharp, some are just a tad off.

I’ll skip right past explaining all the troubleshooting steps I took, and go right to the 1st phone call to Canon Tech Support. The guy really didn’t have a clue and told me to reset the camera to factory default settings – he even told me all DSLRs should be reset at least once each month.

I reset it, but no joy. Single shots were tack sharp. Action shots – following the runner – were tack sharp.

After setting up a tripod and a static target, and shooting a couple of hundred frames using various lenses – I called Canon again. This time I got Mike. I didn’t have 50 words out of my mouth when he said, “Take it off AI Servo.”

AI Servo expects movement - changes in the focus plane of the target - and when it doesn’t see them, it “hunts” just enough to soften the focus.

So I changed it to AI Focus and zipped 20 frames at my target. All of the were tack sharp. Thank-you Mike!

For single frames, any of the 3 settings work (but Single Shot is best). If the subject is moving when you start a continuous shot group, use AI Servo, but if you start with a subject that starts static, and then begins to move, use AI Focus. Problem solved.

Re: Unless there’s motion, don’t use AI SERVO.

cicopo — Mon, 09 May 2016 13:27:22 GMT

I found that too when I first tested my 7D2 but so far none of my other bodies are that fussy. Might be the improvements in the AF system the newer bodies use.

Re: Unless there’s motion, don’t use AI SERVO.

TTMartin — Mon, 09 May 2016 21:15:40 GMT

That advice goes back many years, but it is good to hear it again.

It also is a good reason to review the videos below, even if you have watched them a couple times before.

A Look at The Canon Autofocus System Part 1

A Look at The Canon Autofocus System Part 2

A Look at The Canon Autofocus System Part 3

Re: Unless there’s motion, don’t use AI SERVO.

PajamaGuy — Fri, 13 May 2016 10:34:05 GMT

Thanks - I'd viewed them in 2014 - but they're worth a revisit. Actually, it was after watching Rudy that I pretty much locked the camera onto AI Servo.

So, it now begs the question, "Why not leave it on AI Focus all the time?" - I know I read or heard something about when AI Focus switches from One Shot to AI Servo it's "slower".... I'm searching, but can't find it written as to what is "slower". Is it the 1st frame after it switches to AI Servo?

Does the AI Servo that AI Focus switches to, focus subsequent shots slower than if the camera was set to AI Servo?

When I sit on the foul line beyond 1st base and aim at the batter, AI Focus does a better job of holding focus on the batter than AI Servo did. But as the batter runs toward 1st (directly at me) - some frames are very soft.

I have to test a sequence using each, and also play with the tracking sensitivities, but I am just looking for the explanation of why use AI Servo instead of AI Focus.

Would I be better off to assign a button to execute the "switch between One Shot and AI Servo"?

Thanks!

Re: Unless there’s motion, don’t use AI SERVO.

TTMartin — Fri, 13 May 2016 12:21:25 GMT

@PajamaGuy wrote:
Thanks - I'd viewed them in 2014 - but they're worth a revisit. Actually, it was after watching Rudy that I pretty much locked the camera onto AI Servo.

So, it now begs the question, "Why not leave it on AI Focus all the time?" - I know I read or heard something about when AI Focus switches from One Shot to AI Servo it's "slower".... I'm searching, but can't find it written as to what is "slower". Is it the 1st frame after it switches to AI Servo?

Does the AI Servo that AI Focus switches to, focus subsequent shots slower than if the camera was set to AI Servo?

When I sit on the foul line beyond 1st base and aim at the batter, AI Focus does a better job of holding focus on the batter than AI Servo did. But as the batter runs toward 1st (directly at me) - some frames are very soft.

I have to test a sequence using each, and also play with the tracking sensitivities, but I am just looking for the explanation of why use AI Servo instead of AI Focus.

Would I be better off to assign a button to execute the "switch between One Shot and AI Servo"?

Thanks!

That is one of the scenarios where, BBF or in my opinion better yet reprogramming AF ON to AF OFF comes into play. After your initial focus on the batter with the camera in AIServo, simply suspend AF until the batter starts to move. With BBF you remove the AF start from the shutter and press and hold the AF ON button anytime you want to AF. With the AF OFF option you leave AF start on the shutter button, but, use the back button to stop AF anytime you don't want it. Like to prevent hunting on the batter, or when you want to manually focus, such as to photograph something going on the other side of the chainlink.

You might also benefit from assigning either the AF ON button, or the DOF Preview button to temporarly switch from AIServo to OneShot.

Re: Unless there’s motion, don’t use AI SERVO.

Waddizzle — Fri, 13 May 2016 12:36:15 GMT

"You might also benefit from assigning either the AF ON button, or the DOF Preview button to temporarly switch from AIServo to OneShot."

Whomever decided to put the DOF Preview button, on a 6D, on the front of the camera, out of reach, needs their head examined.

Re: Unless there’s motion, don’t use AI SERVO.

ebiggs1 — Fri, 13 May 2016 13:07:40 GMT

I can tell you how I shoot baseball. Right or wrong, I still get asked by Moms and Dads to do it so I guess it is 'right'.

Switching from multi-point to single-point focusing. Use the focus point at the centre of the frame. It is faster and also lets you tell your camera exactly what you want to focus on, rather than letting it guess. Matter of fact single focus point is best 90% of the time for any shooting.

My favorite lens ia a 300mm f2.8 and kept at f2.8. I never take it off max aperture. Limit the close focus adjustment so the lens doesn't have so far to travel to focus. Set the camera to M (manual). ISO 1200 to 1600. SS at least 1/500. Adjust ISO to maintain this. Even 3200. As stated max aperture, in my case f2.8. I use Ai-Servo. These can and will need some changing as required.

But I will add one step some people don't do and it works very well. That is pre-focus on a point. Wait for the player to get there!

Last point form me to anybody that shoots any kind of sports is, location, location and location. That is the most important part of shooting baseball (or whatever sport).

This is how I do it, Good luck.

Re: Unless there’s motion, don’t use AI SERVO.

ebiggs1 — Fri, 13 May 2016 13:22:22 GMT

Oh, BTW, shoot jpg. Not RAW. Here is one place for jpg over RAW.

Re: Unless there’s motion, don’t use AI SERVO.

Waddizzle — Fri, 13 May 2016 15:07:45 GMT

@ebiggs1 wrote:
Oh, BTW, shoot jpg. Not RAW. Here is one place for jpg over RAW.

Why? Frames Per Second processing speed? File size? I'm pretty sure speeds fits in here somewhere.

Re: Unless there’s motion, don’t use AI SERVO.

kvbarkley — Fri, 13 May 2016 15:52:51 GMT

@Waddizzle wrote:
@ebiggs1 wrote:
Oh, BTW, shoot jpg. Not RAW. Here is one place for jpg over RAW.
Why? Frames Per Second processing speed? File size? I'm pretty sure speeds fits in here somewhere.

I would guess the no real buffer limit, just mash the shutter and go.

Re: Unless there’s motion, don’t use AI SERVO.

PajamaGuy — Fri, 13 May 2016 17:36:55 GMT

You might also benefit from assigning either the AF ON button, or the DOF Preview button to temporarily switch from AIServo to OneShot.

That's where I was leaning.... The DOF button is placed perfectly (sorry Waddizzle ) - and that's the one I use to flip back and forth between focus points.

I'll elaborate later - I just had 6 Medial Branch Block injections, and it's time for a nap...

Re: Unless there’s motion, don’t use AI SERVO.

Waddizzle — Fri, 13 May 2016 18:11:22 GMT

"That's where I was leaning.... The DOF button is placed perfectly (sorry Waddizzle ) - and that's the one I use to flip back and forth between focus points.

I'll elaborate later - I just had 6 Medial Branch Block injections, and it's time for a nap..."

--------------------------------------

The 6D has the button in a difficult spot to press. Here is the 7D Mark II DOF button location.

Here is the 6D DOF button location.

Notice the difference? The arrows are showing you the direction the button should be pushed. Not only is the button half the size, it's further away on the 6D. You have to push it with tip of your finger as you straighten it out, but only if you could reach it.

This button is inaccessible for handheld shooting, which makes it pretty useless.

Re: Unless there’s motion, don’t use AI SERVO.

ebiggs1 — Fri, 13 May 2016 19:40:55 GMT

"Why? Frames Per Second processing speed? File size? I'm pretty sure speeds fits in here somewhere."

And you would be correct. I use my 1D Mk IV for sports which I freely admit I don't do often. I just do it when I get asked to be the photographer or to help the real photographer.

Anyway a Mk IV shoots 10 fps. Its buffer can hold 28 full res RAW files. That's not 3 seconds to full. On jpg it will shoot 125 large jpg or so before filling the buffer. Just holding down the shutter button. It can fire and write 10 large jpg in a second. No delay at all. It is nothing to say but the Mk IV is fast. It is very fast and if you have never used one you don't realize how fast it is.

In RAW it takes 6 or 7 seconds to fire 10 and write to a fast card.

The Mk IV shoots way faster than it or any camera can focus. So the setting I recommended of at least 1/500 and manual mode are critical if you want this kind of speed. 1/640+ is better.

Re: Unless there’s motion, don’t use AI SERVO.

PajamaGuy — Sun, 15 May 2016 09:14:32 GMT

Well, switching from One Shot to AI Servo "in-flight" worked. It resulted in noticeably sharper pics both before movement starts and after. I find it curious that "AI Focus" isn't even mentioned in the "7D MKII AF Guide".

I re-assigned the "*" button to switch the mode to One Shot when pressed, then AI Servo when released. I would really like someone from Canon to explain why that is recommended while AI Focus (which is supposed to do the same thing) isn't even mentioned. I still use the DOF button to switch between wherever I've positioned the focus spot(s) and the centered positions.

I also used default Case #2, and the 8-point AF Point Expansion:Surround - (I know Mr. Biggs likes the single, center point, but the AF Guide specifically recommends against it in favor of the 4 or 8-point surround.)

Re: Unless there’s motion, don’t use AI SERVO.

ebiggs1 — Sun, 15 May 2016 13:33:16 GMT

"... but the AF Guide specifically recommends against it in favor of the 4 or 8-point surround"

All the pros I know or have met use just the center point. Maybe they don't or didn't read the manual?

I can't stress enough the advantage of pre-focus. MF not AF ! Do that as much as you can. Also one thing I forgot to mention is go vertical. Don't forget you can turn the camera when it is best.

But pre-focus and anticipating the shot is a big plus. It is better to be proactive rather than reactive.

Re: Unless there’s motion, don’t use AI SERVO.

jrhoffman75 — Sun, 15 May 2016 15:19:05 GMT

AI Focus isn't really a mode. It's a camera setting that will select One Shot or AI Servo based on whether it detects motion of not. There can be a delay.

Re: Unless there’s motion, don’t use AI SERVO.

TTMartin — Sun, 15 May 2016 15:39:05 GMT

@PajamaGuy wrote:

I also used default Case #2, and the 8-point AF Point Expansion:Surround - (I know Mr. Biggs likes the single, center point, but the AF Guide specifically recommends against it in favor of the 4 or 8-point surround.)

Each generation of camera specific features get better and more reliable. So what someone is comfortable recommending is based on their experience with their cameras. There are people who recommend always shooting in full manual exposure, because early versions of Av or Tv, didn't work as well as they do today. There are people who recommend only using spot or center weighted metering because earlier versions of evaluative metering did work as well as current ones do.

The same goes for the AF system on the 7D Mk II, it is a step up from older AF systems. It uses its 150,000 point IR metering sensor to enhance its AF. When you take into account it is a crop sensor camera, that is around twice the metering points of cameras like the 5D Mk III, and a feature the 1D Mk IV doesn't really have.

Re: Unless there’s motion, don’t use AI SERVO.

PajamaGuy — Mon, 16 May 2016 09:32:31 GMT

Based upon DPP's display of the "points in focus", I need to adjust the "AF point auto switching" to be more sensitive, because it doesn't change. If I was as good as Mr. Biggs is, I'd also use the single center focus point, but I know I can't keep a single point on the subject as he runs the bases, let alone dodging the tacklers as he crosses the yard markers. But if DPP is correct, the AF point isn't changing.

Regarding full manual, I use mostly Av when I know there's enough light to keep my shutter faster than 1/1000. I just lock on the desired aperture, set the minimum shutter speed and maximum ISO and let the camera figure it out.

Re: Unless there’s motion, don’t use AI SERVO.

Waddizzle — Mon, 16 May 2016 13:08:46 GMT

"Regarding full manual, I use mostly Av when I know there's enough light to keep my shutter faster than 1/1000. I just lock on the desired aperture, set the minimum shutter speed and maximum ISO and let the camera figure it out."

No, I would disagree with using a "maximum ISO" setting. Always use the lowest ISO value that circumstances will allow. Yes, you generally want to use the fastest shutter speed that circumstances will allow. You may also want to use the widest aperture that your lens will allow, but be cognizant of shooting distance to your subject and depth of field at longer focal lengths.

In my short experience with shooting baseball [Little League games] I have found that focal lengths ranging from 50-300mm, on a full frame, has been almost ideal for photographing most infield action, with 70-200mm almost being the ideal lens. I have been photographing much of the action around f/5.6-6.3, which gives me good DOF around the infield, with either a Canon EF 100-400mm, or a Sigma 150-600mm. I have found that I like the range of the 100-400mm better for baseball. I find that most of my shots are ranging from 200-300mm.

I have been mostly shooting with just the center point active, One Shot mode, on a 6D, wihch lacks the tracking AF assist points of a 7DmkII. I pre-focus to where I think the action will be forthcoming, and wait it out. You should be able to have better success tracking subjects with a 7DmkII tracking using AI Servo than I would with a 6D. I have also found that shooting from a tripod gives me much sharper photos, which allows me to turn off Image Stabilization so that I can refocus on a new subject, or distance, faster.

Re: Unless there’s motion, don’t use AI SERVO.

PajamaGuy — Mon, 16 May 2016 15:38:22 GMT

Sorry, I didn't speak clearly - when I say maximum ISO, I mean I set the value that I do not want the camera to exceed when on AUTO (usually 1600 for outdoor sports), but like yesterday, it rarely goes above 200.

While I do use f/2.8 a lot, and f/4 when I put on the 1.4x extender, I think I'll play with f/5 - 5.6 when I'm framing just the batter. I'd like to get the catcher a bit sharper. Although my app for DOF says at 110 ft, f/2.8, and 200mm, that the DOF is 9.3 ft. Doesn't that mean that if the catcher's plane is less than 9 ft. from the plane of the batter, focusing on the batter should result in the catcher being in-focus?

I don't pre-focus because I rarely plan the shot. I can usually get 2-3 shots of the batter with the ball in the frame, and once I get a pitcher's timing down, I can get the ball within an inch or two of the bat - but I'm ripping at 10 fps, too. Same thing with tags, slides, and fielding - I'm not good enough to plan, pre-focus, and shoot. That's why focus tracking is important to me.