Realistic AF expectations for a moving toddler?

Short version: is it realistic to expect a Canon 70-200 f/2.8 IS II on a 5D3 to be able to "keep up" with a toddler running towards you?

Long version...

I sent my 70-200 and 5D3 to Canon due to inconsistent focus issues - you could MFA it at a particular camera to subject distance and it'd be fine, but change the distance and it'd consistently be "off". Canon tweaked the lens (and confirmed it wasn't something I could have fixed myself), and tuned it so that its MFA settings for the body are W 0 and T 0. I'd asked them to tell me if the body needed a large tweak as that would've affected my other lenses; fortunately it was apparently pretty close to "0", so was unmodified.

The lens is now good and is producing very sharp images at all distances. However, I'm noticing I'm struggling to get sharp "movement" shots of my toddler, and I'm wondering if my expectations are too high.

An example would be ~90mm focal length, 1/500 sec, f/4.0, ISO 160, camera to subject distance probably 4 to 5m. Toddler... erm, toddling towards you (or past, at a diagonal). I use AF Case 1 on the 5D3 and was using single point with 4 expansion.

Online calculators put the DOF at around 50cm, and that looks about right given the sharpness of the ground, but I find that most shots in that scenario have the middle of the plane of focus maybe 30cm too far back (or occasionally forward) - thus the eyes/head are blurred.

There is evidence of motion blur on hands/feet, but I'm reasonably certain the eyes/head problem is focal plane not motion blur.

Am I being unrealistic with this sort of short distance/medium speed/shallow DOF, and/or is there something I could do to improve matters (other than stopping down to f/16!)?

Just practice. I shoot live bands with manual focus lenses and some hardcore metal bands move around a whole lot more than toddlers.


When I do use AF lenses sometimes I'll prefocus and if they get out of the plane of focus I'll wait until they get back in it to fire off the shutter. Or I will move myself while still half pressing focus locked.

With a higher end body I'd do continuous focus, you pay for those features so why not use them.

maverick75 wrote in post #17652809
Just practice. I shoot live bands with manual focus lenses and some hardcore metal bands move around a whole lot more than toddlers.


When I do use AF lenses sometimes I'll prefocus and if they get out of the plane of focus I'll wait until they get back in it to fire off the shutter. Or I will move myself while still half pressing focus locked.

With a higher end body I'd do continuous focus, you pay for those features so why not use them.

Unfortunately my eyesight isn't good enough to be able to track a target with manual focus. Glasses mean I can't get as close as I'd like to the viewfinder, and without them I'd have no hope of knowing what was in focus. Perhaps with an EVF and a really good focus peaking system I'd stand a chance.

My goal with these shoots is to get a sequence of images with the little one in motion - so prefocussing is really only going to get me one shot (and usually at least one shot is sharp anyway - but of course it's often not the best one from the set).

I'd kinda hope the 5D3 + 70-200II would be considered a sufficiently high-end combination; for Canon there's really only the 1Dx and 7DII that should better it. I am using AI Servo BTW.

Where is the focus point on the out of focus pictures? How long have you been using that combination of equipment? The technology is great but it takes some practice to use it well.

Many of us shoot sports almost daily and if the combination of equipment that you have didn't work it would not be nearly as popular as it is in sports photography.

bpalermini wrote in post #17652817
Where is the focus point on the out of focus pictures? How long have you been using that combination of equipment? The technology is great but it takes some practice to use it well.

Many of us shoot sports almost daily and if the combination of equipment that you have didn't work it would not be nearly as popular as it is in sports photography.

Focus point in the right place - i.e. displaying the focus point on playback via the Q menu usually has the red square roughly were it should be.

I've been using the body and that lens for a couple of years, but mostly for subjects further away ("zoo wildlife", motor sports) or largely static portraits (adults). I don't use the 70-200 that often, but the 5D3 + 24-70II almost daily; and whilst that tends to be mostly static portrait shots I feel I'm comfortable with the gear - just inexperienced with shooting moving targets with long(ish) focal lengths.

What focus mode are you in?

Can you post a sample?

Your ISO is too low. At 160 you are pretty much guaranteed to have blurry shots.

ISO setting is not just for the sharpness of the image but it also is important for freezing movement.

Set your ISO minimum @ 400, with your mark III you'll still get noise free images.

ISO is irrelevant as long as the shutter speed is sufficient.

1/500 is borderline, but should be fine.

your camera and lens certainly should be able to handle the task, if i had a 5DIII i'd help out, but i don't.

Left Handed Brisket wrote in post #17652966
ISO is irrelevant as long as the shutter speed is sufficient.

1/500 is borderline, but should be fine.

your camera and lens certainly should be able to handle the task, if i had a 5DIII i'd help out, but i don't.

False!

awesomeshots wrote in post #17653008
False!

no really, i don't have a 5DIII.

sploo wrote in post #17652804
Short version: is it realistic to expect a Canon 70-200 f/2.8 IS II on a 5D3 to be able to "keep up" with a toddler running towards you?

..

Short answer:

YES!

So the ISO setting can help if it corresponds with making other adjustments.

If you aren't getting the results desired with 1/500 f/4 the simple thing to try is to boost both of those settings, which will require more light, or a higher ISO setting.

try 1/1000 and more depth of field like f/6.3 or more. Adjust ISO to get that and a good exposure.

Of course AF settings and technique can help as well, but I think we often get to concerned with all those Canon menus when what will solve it is the basic exposure settings.

AI Servo, consider using AF ON button and separating it from the shutter in custom controls, and look at your AF case settings, there is one SPECIFICALLY designed for a runner coming at you.

bumpintheroad wrote in post #17652835
What focus mode are you in?

AI Servo

bumpintheroad wrote in post #17652835
Can you post a sample?

Kinda... SHMBO requested that we didn't post any pics of the little one until she's old enough to make the decision on whether she wants to herself. It's a shame, as I occasionally get shots I'd like to share (either because I'm proud of them or to request critique). However, I respect the request, so a crop will have to do.

The image below was shot in portrait format, and is cropped pretty close to exactly the bottom half (to give you an idea of the subject in the frame). Taken at 88mm, 1/500, f/4. I'd guess (based on a FOV calculator and her height) about 5m camera to subject distance.

awesomeshots wrote in post #17652885
Your ISO is too low. At 160 you are pretty much guaranteed to have blurry shots.

ISO setting is not just for the sharpness of the image but it also is important for freezing movement.

Set your ISO minimum @ 400, with your mark III you'll still get noise free images.

ISO on a digital camera is just an amplifier that boosts the signal recorded by the sensor after the shot is taken. Raising it will allow the possibility of getting a sufficiently bright shot in darker conditions, but it's not specifically tied to shutter speed or thus motion blur. A suitable ISO setting may allow a suitable shutter speed, but 160 and 400 are just arbitrary values. If you were meaning "you needed a faster shutter, and in this particular scenario ISO 400 would have allowed that with the same exposure but still with minimal noise" then yes - that's a potential argument (even though I'm not totally sure it's motion blur in this case).

CyberDyneSystems wrote in post #17653024
So the ISO setting can help if it corresponds with making other adjustments.

If you aren't getting the results desired with 1/500 f/4 the simple thing to try is to boost both of those settings, which will require more light, or a higher ISO setting.

try 1/1000 and more depth of field like f/6.3 or more. Adjust ISO to get that and a good exposure.

Of course AF settings and technique can help as well, but I think we often get to concerned with all those Canon menus when what will solve it is the basic exposure settings.

AI Servo, consider using AF ON button and separating it from the shutter in custom controls, and look at your AF case settings, there is one SPECIFICALLY designed for a runner coming at you.

I was going to try f/8, and possibly AI Servo with automatic AF point selection (to follow the subject) but unfortunately we ran out of time for the day. I'd rather not stop down as that's part of the beauty of this lens (moderately long focal length + moderately wide aperture + very nice background blur rendering).

I have looked at the different AF Cases quite a bit. Interestingly whenever I've seen discussion about it (often with 1Dx owning sports shooters) the only consistent thing is that they all disagree on which mode is best for which type of action

EDIT: spelling mistake

Canon's DPP software will tell you which of the camera's focus points was the one to grab focus. It it was one around her waist the plane of focus would be as you described.

Left Handed Brisket wrote in post #17653368
Canon's DPP software will tell you which of the camera's focus points was the one to grab focus. It it was one around her waist the plane of focus would be as you described.

I usually just check on camera (via the Q menu). On her face for the shot I posted. That's what makes me wonder what the problem is; if the target was moving so fast I couldn't keep up with an AF point it would makes sense, but these problem shots invariably have the AF point in the right area.

The camera's set for tracking priority vs release too.