C200: C200 AF, tracking & face detection tips

T

teamjim

Member
Anybody using this and have any tips? I’ve been shooting this week and had a few thoughts. Looking for some tips too.

Manual focus is clearly still best for many situations especially if hectic.

Face detection (face only) is great if there is only 1 face in shot. If the 1st face is lost another face will be selected, not great for eg bride walking down the aisle.

Face detection (face priority) is sort of pointless. If the face is lost it will either go to another face (if other faces in shot) or focus on wherever the square is ... not sure what that is useful for

I find continuous is only good if the subject is still. If subject is moving around it will continuously be focusing in/out of background and foreground subject that is moving around

Tracking is semi-reliable. Good for moving subjects, but ideally needs to be selected before subject moves fast

Tracking + face detection is more reliable apparently than just face, but still not totally reliable.

Anyone got any tips. Thinking particularly about a bride down the aisle from a static position. Select a part of the frame and keep her in that? Tracking? Face? Manual?
 
I hope I’m not just pointing out the obvious, but before we can speak of “totally reliable” this tech needs to undergo several updates...
As you write, tracking and face detection seems most fitting, but I would probably just rely on DPAF and keeping the bride in the AF square, even if this limits framing.
 
I tend to use face priority quite a bit either with one shot or continuous AF with a button turning it off. Most of the time I am trying to track people so the face priority will make it so that I don't have to constantly readjust the tracking. Then, when I switch to objects the square works just fine. I've also discovered that turning down the response and AF speed can help keep the AF from suddenly freaking out. This is on the C300 II so the C200 might be different.
 
Different lens will give different results on the DPAF. I hear the STM lenses are good for that though they only go as low as F3.5. That being said, I wouldn't totally rely on the DPAF in situations where it's a once and done shot.
 
I did a few sit down interviews recently with the Sigma 18-35 Art lens. Great lens. However, several times during the interview, for a few seconds, with face tracking on the subject went out of focus, if it is a crucial part I'm screwed, but I think I can work around this with B roll.

I think that if the subject is against something without a lot of detail it will be fine. If they move a bit into another background area without detail, it might momentarily lose it. I haven't tried the same with my 18-80 which might work better yet just because I needed more shallower depth of field to blur the background. I've also noticed that the AF doesn't track that well in low light.

I may just center the AF box on the subject next time, but still learning the limitations.
 
I use various combinations of DPAF all-the-time. Usually I have face tracking enabled but keep it under my thumb with one push auto. There are times when I will let it roll with continuous control and then in some situations I’ll do AF boosted MF.
While the Canon AF isn’t perfect, there have been times when it get confused by a subject wearing a hat and sunglasses or one that turns away from camera, the amount of times the AF is spot on far outweigh the mistakes. Look, if you are in total manual focus, there are going to be focus mistakes so its not like manual is great and auto is crap...
Use of the various grades of Canon DPAF is situtation and it takes some experience to learn what situation calls for a particular mode...
The DPAF is one of the great features of the Canon C series. Do I wish the C300 MK2 had 120 fps without crop? Sure , but I tell you what- from a use point of view, I use the sh*t out of the various modes of DPAF and 120 fps an order or two of magnitude less.
 
kmoreau893 said:
I did a few sit down interviews recently with the Sigma 18-35 Art lens. Great lens. However, several times during the interview, for a few seconds, with face tracking on the subject went out of focus, if it is a crucial part I'm screwed, but I think I can work around this with B roll.
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This has happened to me a few times, even in situations where there was no reason it should have lost track of the face. I'm starting to use tracking instead of Continuous AF for interview situations. Seems to be working better, but I need some more time to really evaluate. Plus I don't have to change AF modes which is a PITA, even with a button shortcut.
 
Tcap said:
I hear the STM lenses are good for that though they only go as low as F3.5.
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The 50 has a F1.8 the 24 and the 40 both have F2.8. STM is smoother, USM is faster, hence the L-lenses have it as their focus is photography.
 
brettsherman said:
This has happened to me a few times, even in situations where there was no reason it should have lost track of the face. I'm starting to use tracking instead of Continuous AF for interview situations. Seems to be working better, but I need some more time to really evaluate. Plus I don't have to change AF modes which is a PITA, even with a button shortcut.
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So last night I shot about 90 minutes of a presentation given by Tom Friedman of the NYT. I used continuous focus, face tracking , face priority and once in the 90 minutes the lens lost its place and really buzzed focus before regaining sharp. THere was lots of movement by the speaker, turning profile in both directions and everything in between, plus walking about the stage area. Lens was the 70-200 2.8 ll and most of the time the exposure was a 3.5 or 4.0.
If I had tried to track this manually, I don't think I would have done as well as the camera managed to do.
 
Mark Smith said:
If I had tried to track this manually, I don't think I would have done as well as the camera managed to do.
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I agree. And I can concentrate things other than focus when the AF system is handling that. The combination of face detection and tracking seems to be working well for me. Here it is quoted in the C200 manual:

"If you use face detection together with the tracking function (A 88), the camera will be able to track the selected main subject more reliably"
 
For me, shooting narrative, the most important AF function is actually AF Lock. Toggling the AF on and off is super important for preventing random freak outs, if you know you have someone in focus, and there's enough depth of field, and you're going to be switching to focussing on something else, turn it off for that beat, select a new target, reactivate it when the moment comes. You can even start tracking a new face while AF is disabled. Personally I have FUNC 1 on the monitor as AF Lock, and FUNC 8 as well, so that the assistant and operator can both have the option to be using it that way depending on the shot.
 
IanTheM said:
For me, shooting narrative, the most important AF function is actually AF Lock. Toggling the AF on and off is super important for preventing random freak outs,


I tend to use One push Auto with face detection and tracking enabled. I can see how One push auto and AF lock are similar and can acheive similar ends but in different ways . With one push auto I can mnual focus all I want then when I need a focus reality check, I can hit the AF button and get one quickly.
Using AF lock , I can let the AF do its thing if I am shooting a group of people who are relatively close and in sort of stable relationship spatially with the camera , and then freeze the AF as necessary.
I would say that these are complimentary focus strategies and both work.
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