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Gear Talk => EOS Bodies - For Stills => Topic started by: bjd on January 12, 2013, 07:49:45 AM

Title: My (seemingly) never ending Focus woes ... BIF advice needed
Post by: bjd on January 12, 2013, 07:49:45 AM
Hi,
though I would start a new thread for this after hijacking this one a while ago:
Quote
http://www.canonrumors.com/forum/index.php?topic=11978.msg213260#msg213260
.

I'm trying to work methodically through the various AF settings as I could never get AF to work well with BIF (Birds in Flight) in my garden. So please bear with me. For my tests I stood by the side of the road and using low-speed continuous shooting took shots as cars came into view and crossed the field of view. Most of them will have been driving around 30-60Kph.
I assume the Camera should be able to handle this situation. Agreed?
Lens is a 70-200 F2:8 L IS II USM (Group A), IS on set to mode 2.  AF point selection set to automatic.

First point. If I set the camera to Automatic (A+), then it will focus on something nearby which is at the side of the AF points. See the picture Focus1. IMHO that is correct.

Now, if I switch to AV, now in AI-Servo AF, then it will only focus using the center points. I tried various Av and Tv settings, I could never get anything other that the center points to "Lock" (flash red).  Picture Focus2.jpg. I was using AF Case 3 here, expecting
Quote
In Case 3, the [Tracking sensitivity] parameter is set to [+1]. As a result, subjects that come into the AF points will be focused on more quickly. This setting is most
effective when subjects appear suddenly in the frame (for example photographing skiers in an alpine skiing downhill race,).
I get the effect that it has locked onto someting in the background (Focus3.jpg) and does not change focus even if the car crosses in front of the object that was in focus. Plus, it never tries to follow the car anyway. See Focus4.jpg.
This was done with the three parameters set to default and then tried to increase Tracking sensitivity to +2 without any effect. Now as the AF wont follow a car, I'm not surprised that it doesn't follow a small bird.

I'd appreciate any hints of what I may be doing wrong.

Cheers Brian
Title: Re: My never ending Focus woes with my 5DMK3
Post by: spinworkxroy on January 12, 2013, 08:33:19 AM
Correct me if i'm wrong, but when the camera is in Ai-Servo mode..it shouldn't flash red at all right? That IS an inconvenience with the 5D3 that many people have complained about…where it's impossible to know which points the camera is at when the red squares don't light up in Ai-Servo…
I've not actually used it before..maybe i should give it a shot and see if i face the same issues..
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 12, 2013, 08:58:43 AM
Hey,

I'm not interested in the focus point flashing, its the fact that its not picking up the movement and focusing on that. Sorry if I wasn't clear on that.

Cheers Brian
Title: Re: My never ending Focus woes with my 5DMK3
Post by: ddl on January 12, 2013, 09:22:29 AM
Do you have the center AF point selected first? If so then it's waiting for that object at the focus point to move it appears.

When using [Auto selection of 61 AF points]
during [AI Servo AF], focusing will start from
the manually selected AF point, the camera will
the automatically change the AF point selecting
from all 61 points as the subject moves.

From Bottom Left on Page 34: http://cpn.canon-europe.com/files/product/cameras/eos_5d_mark_iii/EOS_5D_Mark_III_AF_setting_guidebook.pdf (http://cpn.canon-europe.com/files/product/cameras/eos_5d_mark_iii/EOS_5D_Mark_III_AF_setting_guidebook.pdf)
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 12, 2013, 10:44:54 AM
Hi ddl,
it looks suspiciously like that. But then I have to ask "what is the manually selected AF point?". In my case it always tries to select a focus point at the center and I cannot get it to focus using one of the outer points.
In A+ I can get it to focus using the rightmost column of points at 1/250th and F5.0, if I switch to M and set 1/250th and F5.6 then I can get the fourth row from the right to focus. I tried using evaluative metering too instead of spot, but that doesn't change anything.
Strange

Cheers
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 12, 2013, 10:52:41 AM
1DX does the same thing.  I shot a diving meet last night and zone AF, no matter which tracking case, couldn't lock on the diver all the way through.  It would focus on stupid things in the background every 3rd shot.  I was in extremely low light, however, and that no doubt contributed to this.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 12, 2013, 11:01:24 AM
I especially waited for good light to try this out.
Cheers
Title: Re: My never ending Focus woes with my 5DMK3
Post by: ddl on January 12, 2013, 11:07:28 AM
Somehow the camera needs to know where to start which is why you have to manually pick a point over the object you want to track. After that the camera will try to keep focus on that object if it moves by selecting different AF points.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 12, 2013, 11:24:58 AM
Quote
In Case 3, the [Tracking sensitivity] parameter is set to [+1]. As a result, subjects that come into the AF points will be focused on more quickly. This setting is most
effective when subjects appear suddenly in the frame (for example photographing skiers in an alpine skiing downhill race,).
But I have to point the focus point there, or in its general direction first, till the object hs been picked up I assume.
I had read the guide such that it would go straight for the movement. I thought that in most cases it would automatically go for the nearest object covered by a focus point.

Just tried the following. Background is clear sky, to the left is the corner of a wall. Point camera at sky,
shutter relase half pressed, now slowly pan camera to the left. No reaction till the 4th AF point column from the left is over the wall/sky line, now it has picked up the wall. As soon as it has picked it up then AF points in the 2nd and 3rd rows pick the wall up too.

So I'm still wondering why the left most column does not pick up the wall, or the post as shown in focus2.jpg?

Cheers Brian
Title: Re: My never ending Focus woes with my 5DMK3
Post by: christianronnel on January 12, 2013, 11:26:29 AM
Hi ddl,
it looks suspiciously like that. But then I have to ask "what is the manually selected AF point?". In my case it always tries to select a focus point at the center and I cannot get it to focus using one of the outer points.
In A+ I can get it to focus using the rightmost column of points at 1/250th and F5.0, if I switch to M and set 1/250th and F5.6 then I can get the fourth row from the right to focus. I tried using evaluative metering too instead of spot, but that doesn't change anything.
Strange

Cheers

First of all, having the camera in M, Av, Tv or even P mode has nothing to do with AF.  Those modes deal with exposures.  You can set the focus point with any of those modes.  Secondly, in A+ modes, you are letting the camera do all the decisions for you, both the exposure and what to focus on.  The AF cases wasn't designed for that style of shooting, if you call that a style at all.

For shooting birds in flight (or divers), I suggest to change your Selectable AF point to only cross-type.  That is located on the 4th section of the AF tab menu.  Just know that if you do this, the camera will only allow the cross-type points available for the attached lens and is normally dictated by the lens' maximum aperture.  With this selected, change the way the AI Servo works.  Go to the 2nd section of the AF tab.  Set the AI Servo 1st image priority to focus.  Set the AI Servo 2nd image priority to focus.  Now you can play with the "AF cases" if you want.  I personally leave it on Case 1.  I don't see any practical difference in any of those "Cases."

As for the red dot/focus point flashing,  this is irrelevant on AI servo mode.  If you want to see where you are focusing, you can set the AF point display during focus on 5th section of the AF tab to Selected (pre-AF, focused).

Remember, none of these will do you any good if you're shooting on the green mode.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 12, 2013, 11:34:21 AM
Hi ddl,
it looks suspiciously like that. But then I have to ask "what is the manually selected AF point?". In my case it always tries to select a focus point at the center and I cannot get it to focus using one of the outer points.
In A+ I can get it to focus using the rightmost column of points at 1/250th and F5.0, if I switch to M and set 1/250th and F5.6 then I can get the fourth row from the right to focus. I tried using evaluative metering too instead of spot, but that doesn't change anything.
Strange

Cheers

First of all, having the camera in M, Av, Tv or even P mode has nothing to do with AF.  Those modes deal with exposures.  You can set the focus point with any of those modes.  Secondly, in A+ modes, you are letting the camera do all the decisions for you, both the exposure and what to focus on.  The AF cases wasn't designed for that style of shooting, if you call that a style at all.

For shooting birds in flight (or divers), I suggest to change your Selectable AF point to only cross-type.  That is located on the 4th section of the AF tab menu.  Just know that if you do this, the camera will only allow the cross-type points available for the attached lens and is normally dictated by the lens' maximum aperture.  With this selected, change the way the AI Servo works.  Go to the 2nd section of the AF tab.  Set the AI Servo 1st image priority to focus.  Set the AI Servo 2nd image priority to focus.  Now you can play with the "AF cases" if you want.  I personally leave it on Case 1.  I don't see any practical difference in any of those "Cases."

As for the red dot/focus point flashing,  this is irrelevant on AI servo mode.  If you want to see where you are focusing, you can set the AF point display during focus on 5th section of the AF tab to Selected (pre-AF, focused).

Remember, none of these will do you any good if you're shooting on the green mode.

I did all that stuff.  It still doesn't work that well.  My cases aren't in good light; mine are in bad lighting.  I concede that I may be asking the camera to do something unreasonable.  Even with cross-type only points in AI Servo mode, even though the diver is closer to me than anything, down throughout the dive the AF point will still go back and hit the wall, for some unknown reason, at least twice.  The reason is because the wall is grayish/white and is lighted up more than the diver.  This will confuse any AF system.  To the OP, you have to pay attention to back-lighting too.

Good discussion so far.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: christianronnel on January 12, 2013, 11:42:22 AM
I did all that stuff.  It still doesn't work that well.  My cases aren't in good light; mine are in bad lighting.  I concede that I may be asking the camera to do something unreasonable.  Even with cross-type only points in AI Servo mode, even though the diver is closer to me than anything, down throughout the dive the AF point will still go back and hit the wall, for some unknown reason, at least twice.  The reason is because the wall is grayish/white and is lighted up more than the diver.  This will confuse any AF system.  To the OP, you have to pay attention to back-lighting too.

Good discussion so far.
If you have manually selected the AF point and are subject tracking, there's no way for the camera to switch the AF points regardless of the contrast.  It will try to focus using your selected point.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: East Wind Photography on January 12, 2013, 11:49:48 AM
I agree with your assessment here.  Not all of the AF points are sensitive to the same kind of edge detection and some just are flat out not available depending on the lens used (Maximum aperture).  2.8, 4, 5.6, and in April, F8 are pretty much where things change as far as AF is concerned.  The Manual explains which AF points are used depending on the maximum Fstop of the lens (and I assume extender combination as well).  Though I have seen quite a difference in AF capability between an F5.6 lens and a 2.8 with a 2X extender at 5.6.  Even though the Fstops are essentially the same, there is some difference in the operation of AF, with the 2,8 and extender being marginally better at locking on low contrast objects.

For what it's worth, the 9 point system was much simpler to use and understand.  now with all of these different points, cross, vertical, horizontal, it makes it more complicated to implement and it's imperative that a photographer understand whats going on in that regard with a particular lens to avoid an AF trap.

Hi ddl,
it looks suspiciously like that. But then I have to ask "what is the manually selected AF point?". In my case it always tries to select a focus point at the center and I cannot get it to focus using one of the outer points.
In A+ I can get it to focus using the rightmost column of points at 1/250th and F5.0, if I switch to M and set 1/250th and F5.6 then I can get the fourth row from the right to focus. I tried using evaluative metering too instead of spot, but that doesn't change anything.
Strange

Cheers

First of all, having the camera in M, Av, Tv or even P mode has nothing to do with AF.  Those modes deal with exposures.  You can set the focus point with any of those modes.  Secondly, in A+ modes, you are letting the camera do all the decisions for you, both the exposure and what to focus on.  The AF cases wasn't designed for that style of shooting, if you call that a style at all.

For shooting birds in flight (or divers), I suggest to change your Selectable AF point to only cross-type.  That is located on the 4th section of the AF tab menu.  Just know that if you do this, the camera will only allow the cross-type points available for the attached lens and is normally dictated by the lens' maximum aperture.  With this selected, change the way the AI Servo works.  Go to the 2nd section of the AF tab.  Set the AI Servo 1st image priority to focus.  Set the AI Servo 2nd image priority to focus.  Now you can play with the "AF cases" if you want.  I personally leave it on Case 1.  I don't see any practical difference in any of those "Cases."

As for the red dot/focus point flashing,  this is irrelevant on AI servo mode.  If you want to see where you are focusing, you can set the AF point display during focus on 5th section of the AF tab to Selected (pre-AF, focused).

Remember, none of these will do you any good if you're shooting on the green mode.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: East Wind Photography on January 12, 2013, 11:54:47 AM
Yep it you have a high contrast horizontal object in the background and an AF point is sensitive to that it will take priority over the low contrast vertical edge of the diver.  I either use spot AF or ALL AF points and lock using the center point initially and let the AF system track the edges for me.

I'll add it's still not 100% unless I use center point only and track on the swim shorts.

1DX does the same thing.  I shot a diving meet last night and zone AF, no matter which tracking case, couldn't lock on the diver all the way through.  It would focus on stupid things in the background every 3rd shot.  I was in extremely low light, however, and that no doubt contributed to this.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 12, 2013, 12:12:55 PM
First of all, having the camera in M, Av, Tv or even P mode has nothing to do with AF.  Those modes deal with exposures.  You can set the focus point with any of those modes.  Secondly, in A+ modes, you are letting the camera do all the decisions for you, both the exposure and what to focus on.  The AF cases wasn't designed for that style of shooting, if you call that a style at all.
I know, and I dont use it, but, something works differently when it is set. And I wish I knew what setting causes that.
Remember, none of these will do you any good if you're shooting on the green mode.
True, but I am still intrigued why the outer column will do what I want in green mode,
but not when set to Av, Tv or M. Thats why I set the same parameters in M as were used in A+,
but it made no difference.
I have not selected any AF points, I let the camera do automatic selection.

Also I am using cars as they are a lot more predictable than birds. I though that if I could get it
to work with cars then I'll go back to birds after that and hone the settings.
Cheers Brian
Title: Re: My never ending Focus woes with my 5DMK3
Post by: Portrait_Moments_Photogra on January 12, 2013, 12:36:19 PM
it seems like you forgot an IMPORTANT THING

pls review your manual at page 73 and page 77

61 point automatic selection AF both in A+ and AI Servo Modes

dont worry, there's nothing wrong with your 5D3, just wrong user settings. :)

we all experience it - one way or the other.

Title: Re: My never ending Focus woes with my 5DMK3
Post by: jp121 on January 12, 2013, 02:09:14 PM
There's a very good video on B&H Learn in Depth on Canon AF. It comes in 3 parts.
http://www.bhphotovideo.com/indepth/photography/tips-solutions/look-canon-autofocus-system-part-1 (http://www.bhphotovideo.com/indepth/photography/tips-solutions/look-canon-autofocus-system-part-1)

It explained to me what each Focus points looks for & what is special about Cross-type points. How to use servo etc

I think the problem is that the car has no contrast points for the AF to lock on to. Or more specifically aiming all the focus points at the car is not the right way. You have to aim one of the little boxes at a point with contrast that contains either a horizontal or vertical line.

Plus you have to give the AF system a moment to focus & lock the target.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: ddl on January 12, 2013, 03:04:01 PM
At about 19 minutes in the first B&H video it says for AI Servo that the camera starts to track with the CENTER AF point and if the subject moves off center the camera now uses the outer AF points to continue to follow it.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: jonathan7007 on January 12, 2013, 03:08:02 PM
All,
This is a valuable thread that I will revisit with manual and my own Mk3 in hand, because I have had focus problems and inconsistencies with my Mk3 that have lost shots. I have spoken to other pros with the same experience.

Absent in this thread is the caveat that there may be "focusability" (made-up word) inconsistencies between Mk3 bodies. Manufacturing? Who knows. So CR posters reply with their bodies' performance in described situations (extremely valuable feedback) but it can hard to determine to scientific tolerances where the problem lies with so many variables.

As a CPS member I sent my Mk3 to Canon once (expensive action where I live) with documentation and I got a "could not reproduce..." letter. I know that recreating the shooter's exact conditions and issue is nearly impossible. If that's the criteria it will be tough to get satisfaction, but that is reasonable -- or more exactly "realistic" -- for a manufacturer to require.

So I will
1. continue to learn more about my Mk3, because I recognize that that *I* may be the problem and
2. probably sell my body to someone with lower AF expectations/needs and try not to agonize over the cash lost in swapping copies. (I bought mine early summer so no discount)

This post is also a thank you to all who post here, especially the regulars that shoot tough situations -- with professional-level expectations -- all the time, like bdunbar, PWP, neuro, others.

jonathan7007

Title: Re: My never ending Focus woes with my 5DMK3
Post by: East Wind Photography on January 12, 2013, 03:43:12 PM
One other thing to point out is that the AF system on an camera will have trouble if the subject you are focusing on is too small.  As In the example below of the car going through the field of view, if the car were bigger as in using a telephoto lens, the AF would be more accurate.

I run into issues with catching birds in flight if they are too far away and on noisy backgrounds.  You just have to understand the limitations or use a longer lens when you can.

I don't believe the camera is at fault.  You can try in such circumstances to use a single focus point and use the joystick to get the AF onto the subject be it the grill of a car or the eye of an eagle.  The issue is not unique to the 5d3.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 12, 2013, 04:22:34 PM
I did all that stuff.  It still doesn't work that well.  My cases aren't in good light; mine are in bad lighting.  I concede that I may be asking the camera to do something unreasonable.  Even with cross-type only points in AI Servo mode, even though the diver is closer to me than anything, down throughout the dive the AF point will still go back and hit the wall, for some unknown reason, at least twice.  The reason is because the wall is grayish/white and is lighted up more than the diver.  This will confuse any AF system.  To the OP, you have to pay attention to back-lighting too.

Good discussion so far.
If you have manually selected the AF point and are subject tracking, there's no way for the camera to switch the AF points regardless of the contrast.  It will try to focus using your selected point.

Who said I selected one point?  If I remember correctly, I stated I was using zone with only cross types selected, auto AF point selection.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 12, 2013, 04:38:07 PM
Yep it you have a high contrast horizontal object in the background and an AF point is sensitive to that it will take priority over the low contrast vertical edge of the diver.  I either use spot AF or ALL AF points and lock using the center point initially and let the AF system track the edges for me.

I'll add it's still not 100% unless I use center point only and track on the swim shorts.

1DX does the same thing.  I shot a diving meet last night and zone AF, no matter which tracking case, couldn't lock on the diver all the way through.  It would focus on stupid things in the background every 3rd shot.  I was in extremely low light, however, and that no doubt contributed to this.

YES!
Title: Re: My never ending Focus woes with my 5DMK3
Post by: christianronnel on January 12, 2013, 04:54:14 PM
At about 19 minutes in the first B&H video it says for AI Servo that the camera starts to track with the CENTER AF point and if the subject moves off center the camera now uses the outer AF points to continue to follow it.
Personally, I prefer to track the subject manually rather than relying on the camera to switch AF points.  I seem to get better result that way.  Most of us naturally track subjects the same way anyway, so why not just choose a fixed AF point?  Even the presenter stated that Auto AF point selection is convenient for some situations but with lots of limitations.  I think sports shooters should really practice selecting their AF points and subject tracking.


Who said I selected one point?  If I remember correctly, I stated I was using zone with only cross types selected, auto AF point selection.
Sorry, I wasn't clear.  I was actually suggesting to manually select AF point next time instead of auto AF selection.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: ddl on January 12, 2013, 06:52:57 PM
I track manually with the camera as well rather than relying on the focus points to follow the subject.

I posted this as I thought it might help the OP with his problem.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 12, 2013, 10:05:46 PM
At about 19 minutes in the first B&H video it says for AI Servo that the camera starts to track with the CENTER AF point and if the subject moves off center the camera now uses the outer AF points to continue to follow it.
Personally, I prefer to track the subject manually rather than relying on the camera to switch AF points.  I seem to get better result that way.  Most of us naturally track subjects the same way anyway, so why not just choose a fixed AF point?  Even the presenter stated that Auto AF point selection is convenient for some situations but with lots of limitations.  I think sports shooters should really practice selecting their AF points and subject tracking.


Who said I selected one point?  If I remember correctly, I stated I was using zone with only cross types selected, auto AF point selection.
Sorry, I wasn't clear.  I was actually suggesting to manually select AF point next time instead of auto AF selection.

Oh ok, sorry for the confusion.

Here's another problem I thought of.  Suppose you are again shooting swimming.  You want to shoot the swimmers at the start of the race of a backstroke race.  You focus on the back of the head of the swimmer, who is facing away from you.  The "beep" goes and you want to shoot the swimmer from release all the way back and into the water.  Since the swimmer's head will come back towards you rapidly, I have not been able to get this sequence all in focus with a burst mode, because the swimmer moves so quickly so it appears the AF cannot keep up.  Perhaps this is another impossible task, but it's interesting that I tried to do it, with failure of course :).
Title: Re: My never ending Focus woes with my 5DMK3
Post by: christianronnel on January 12, 2013, 11:24:53 PM
Here's another problem I thought of.  Suppose you are again shooting swimming.  You want to shoot the swimmers at the start of the race of a backstroke race.  You focus on the back of the head of the swimmer, who is facing away from you.  The "beep" goes and you want to shoot the swimmer from release all the way back and into the water.  Since the swimmer's head will come back towards you rapidly, I have not been able to get this sequence all in focus with a burst mode, because the swimmer moves so quickly so it appears the AF cannot keep up.  Perhaps this is another impossible task, but it's interesting that I tried to do it, with failure of course :).
I'm not exactly sure, but with back-stroke, the head never goes under water, right?  Is that a similar scenario as a runner running towards you?  If it is, I have been able to capture runners well with just the settings I described earlier, in AI servo and with the focus point selected where I think their head would be.

Here's a cheetah running towards me.  I took it with my measly 70-300L so subject in the frame is far too tiny to post but most of the images in the entire series look in focus.  That cheetah was clocked at just over 50MPH on that run, surely a swimmer would be slower.  I don't know  how hard would it be to track if the lens is at f2.8.
(http://farm9.staticflickr.com/8499/8373621363_2cc09cb417_n.jpg) (http://www.flickr.com/photos/ianmartinez/8373621363/)
m a j a n i @ 50+ miles/hour (http://www.flickr.com/photos/ianmartinez/8373621363/#) by Christian Ronnel (http://www.flickr.com/people/ianmartinez/), on Flickr
(http://farm9.staticflickr.com/8508/8374694280_11340d268a_n.jpg) (http://www.flickr.com/photos/ianmartinez/8374694280/)
Africa's spotted sprinter (http://www.flickr.com/photos/ianmartinez/8374694280/#) by Christian Ronnel (http://www.flickr.com/people/ianmartinez/), on Flickr
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 12, 2013, 11:31:23 PM
Excellent shots!!

I didn't explain my backstroke situation clearly, as I reread it and I couldn't even figure out what I was talking about.  My problem was at the start of the race, where the swimmers are stationary, and then when the gun goes off, they quickly "snap" back, flip, and head into the water.  I was trying to lock focus on the back of the head, stationary, then the gun goes off and they flip back rapidly, and was not able to keep focus since they flipped back towards me.

Your settings work really well for backstroke swimmers, yes, during the race.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: christianronnel on January 13, 2013, 12:13:02 AM
Thanks!

I guess I'm still confused or I really don't know what I'm talking about.  If I remember correctly, with back-stroke, at the beginning of the race the swimmers are already facing the wall.  Depending on which end of the pool you may be located, they either start facing you (closest) or you have the back of their heads (far end).  If I understand you correctly, you are on the far side of the pool.  In that case you focused on the back of the head and when they kick, you see the top of the head to their chin depending on the height you were shooting.  In that case I'm not sure if there's a difference between focusing on the back of the head and track to something like a face.  My guess would be that it should be the same.  If you are located near the starting point (I'm not sure if that's even allowed) then I can understand what you mean when they flip and kick when they reach the other end of the pool.  In that case, I'm not sure I'll do anything different.  I must admit I'm curious now.  It would be cool to shoot a swimming competition.  I've only assisted on cycling and running races.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bdunbar79 on January 13, 2013, 12:40:43 AM
Yeah, I hadn't really done any swimming before either.  I was straight down the pool at the opposite end of the swimmers.  I wasn't allowed near the start due to F.A.T. at the start and finish line.  I'm going to look at my shots and think about this some more.  Thanks.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 13, 2013, 01:39:12 AM
There's a very good video on B&H Learn in Depth on Canon AF. It comes in 3 parts.
http://www.bhphotovideo.com/indepth/photography/tips-solutions/look-canon-autofocus-system-part-1 (http://www.bhphotovideo.com/indepth/photography/tips-solutions/look-canon-autofocus-system-part-1)

It explained to me what each Focus points looks for & what is special about Cross-type points. How to use servo etc

I think the problem is that the car has no contrast points for the AF to lock on to. Or more specifically aiming all the focus points at the car is not the right way. You have to aim one of the little boxes at a point with contrast that contains either a horizontal or vertical line.

Plus you have to give the AF system a moment to focus & lock the target.
HI, thanks for the link, I'll certainly be studying the videos today. 
As I have focus problems with BIF I tried the, what I hoped would be a simpler, situation for the camera  with the moving cars. I only posted a few shots here, but as the car moves across the center of shot, I had assumed that one of the center points would lock on somewhere (as various parts, lines etc. cross) and it would at least follow from then on towards the left of frame.
Having the cars cross at an angle to me and not at 90° would I thought have given the Camera the time needed. We'll see.
Thanks to everyone who contributed here.
Cheers Brian
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 13, 2013, 11:23:10 AM
it seems like you forgot an IMPORTANT THING

pls review your manual at page 73 and page 77

61 point automatic selection AF both in A+ and AI Servo Modes

dont worry, there's nothing wrong with your 5D3, just wrong user settings. :)

we all experience it - one way or the other.
Wife says we can't afford a new user, so its up to me still.
My manual is in German so not totally certain what points you are referring to as the page numbers may be different.
I watched all three videos and read the book (EOS_5D_Mark_III_AF_setting_guidebook.pdf) again. With AI Servo AF with all 61 points used, it says "Shooting started by pinpointing focus on the leader of a cycling road race with a manually selected AF point". I'm still unclear on the "manually selected AF point", the large picture on page 53 shows 61 points in use.
Just testing getting the camera to focus on a stationary object indoors, it will do that with one of the outer points. Selecting the point or points it uses on its own.
When shooting BIF, usually pretty small ones in our garden, I find I need to anticipate a lot in which direction they will move, for example when taking off. So I will try to track them as much as possible, but I'm hoping for some assistance from the 61 points to get/keep the bird sharp as long as its under an AF point.   

Anyway thanks to everyone for the help and patience.
Cheers Brian



Title: Re: My never ending Focus woes with my 5DMK3
Post by: East Wind Photography on January 13, 2013, 11:30:46 AM
You can go to usa.canon.com and download the English version of the manual for free.

it seems like you forgot an IMPORTANT THING

pls review your manual at page 73 and page 77

61 point automatic selection AF both in A+ and AI Servo Modes

dont worry, there's nothing wrong with your 5D3, just wrong user settings. :)

we all experience it - one way or the other.
Wife says we can't afford a new user, so its up to me still.
My manual is in German so not totally certain what points you are referring to as the page numbers may be different.
I watched all three videos and read the book (EOS_5D_Mark_III_AF_setting_guidebook.pdf) again. With AI Servo AF with all 61 points used, it says "Shooting started by pinpointing focus on the leader of a cycling road race with a manually selected AF point". I'm still unclear on the "manually selected AF point", the large picture on page 53 shows 61 points in use.
Just testing getting the camera to focus on a stationary object indoors, it will do that with one of the outer points. Selecting the point or points it uses on its own.
When shooting BIF, usually pretty small ones in our garden, I find I need to anticipate a lot in which direction they will move, for example when taking off. So I will try to track them as much as possible, but I'm hoping for some assistance from the 61 points to get/keep the bird sharp as long as its under an AF point.   

Anyway thanks to everyone for the help and patience.
Cheers Brian
Title: Re: My never ending Focus woes with my 5DMK3
Post by: neuroanatomist on January 13, 2013, 11:41:32 AM
With AI Servo AF with all 61 points used, it says "Shooting started by pinpointing focus on the leader of a cycling road race with a manually selected AF point". I'm still unclear on the "manually selected AF point", the large picture on page 53 shows 61 points in use.

In Servo with 61-pt auto, use the multicontroller (joystick) to select an AF point before you start focusing (pressing AF-ON or shutter half-press).  The AF system will lock onto the subject at that selected point and track it (depending on your settings).
Title: Re: My never ending Focus woes with my 5DMK3
Post by: Mr Bean on January 15, 2013, 06:54:13 PM
When shooting BIF, usually pretty small ones in our garden, I find I need to anticipate a lot in which direction they will move, for example when taking off. So I will try to track them as much as possible, but I'm hoping for some assistance from the 61 points to get/keep the bird sharp as long as its under an AF point.   
I'm going through the same hoops and learning curves with BIF. I've only started playing with the 5D m3 with BIF over the past month and its been interesting :)

My first example of a BIF pic tracked beautifully, with the camera set to AI Servo Focus, I managed to track the background (just in front of the bird) successfully for at least 6 shots :)

I put it down to my over tracking to start with, meaning the camera "thought" I wanted to focus 2m in front. Oh well, at least it's not film ;)
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 18, 2013, 03:44:14 PM
You can go to usa.canon.com and download the English version of the manual for free.

it seems like you forgot an IMPORTANT THING

pls review your manual at page 73 and page 77

61 point automatic selection AF both in A+ and AI Servo Modes

dont worry, there's nothing wrong with your 5D3, just wrong user settings. :)

we all experience it - one way or the other.
That was a very good suggestion. Now I can immediately find the things you all were talking about in the manual. Still no real sucess though. I hope to get out tomorrow with the camera and try some more.
Cheers Brian

Title: Re: My never ending Focus woes with my 5DMK3
Post by: Dylan777 on January 19, 2013, 11:25:58 AM
With AI Servo AF with all 61 points used, it says "Shooting started by pinpointing focus on the leader of a cycling road race with a manually selected AF point". I'm still unclear on the "manually selected AF point", the large picture on page 53 shows 61 points in use.

In Servo with 61-pt auto, use the multicontroller (joystick) to select an AF point before you start focusing (pressing AF-ON or shutter half-press).  The AF system will lock onto the subject at that selected point and track it (depending on your settings).

+1....When my kids running around, I use 61-pt auto in servo very often.

You must lock-on the subject first and do not release that shutter until you ready take pictures.

To me, case 2-6 are like presets. Therefore, I'm using case1 and set it to my shooting style)

My setting: Case-1
1. Tracking Sen 0 (I only want the camera to track selected subject and ignore others)
2. Accel/Decel Tracking 1 (sometime to zero, since my 4yrs is not that super fast)
3. AF pt auto switching 1

It works everytime ;) 
Title: Re: My never ending Focus woes with my 5DMK3
Post by: Skulker on January 19, 2013, 12:06:47 PM
When you get it right it is quite amazing.

with the full area selected for focusing, you then select were you want it to start. Then it focus on that area and follows it around, it is programed to notice faces and eyes.

Its quite outstandingly good.   8)
Title: Re: My never ending Focus woes with my 5DMK3
Post by: Hobby Shooter on January 19, 2013, 09:04:08 PM
Hi ddl,
it looks suspiciously like that. But then I have to ask "what is the manually selected AF point?". In my case it always tries to select a focus point at the center and I cannot get it to focus using one of the outer points.
In A+ I can get it to focus using the rightmost column of points at 1/250th and F5.0, if I switch to M and set 1/250th and F5.6 then I can get the fourth row from the right to focus. I tried using evaluative metering too instead of spot, but that doesn't change anything.
Strange

Cheers

First of all, having the camera in M, Av, Tv or even P mode has nothing to do with AF.  Those modes deal with exposures.  You can set the focus point with any of those modes.  Secondly, in A+ modes, you are letting the camera do all the decisions for you, both the exposure and what to focus on.  The AF cases wasn't designed for that style of shooting, if you call that a style at all.

For shooting birds in flight (or divers), I suggest to change your Selectable AF point to only cross-type.  That is located on the 4th section of the AF tab menu.  Just know that if you do this, the camera will only allow the cross-type points available for the attached lens and is normally dictated by the lens' maximum aperture.  With this selected, change the way the AI Servo works.  Go to the 2nd section of the AF tab.  Set the AI Servo 1st image priority to focus.  Set the AI Servo 2nd image priority to focus.  Now you can play with the "AF cases" if you want.  I personally leave it on Case 1.  I don't see any practical difference in any of those "Cases."

As for the red dot/focus point flashing,  this is irrelevant on AI servo mode.  If you want to see where you are focusing, you can set the AF point display during focus on 5th section of the AF tab to Selected (pre-AF, focused).

Remember, none of these will do you any good if you're shooting on the green mode.

I did all that stuff.  It still doesn't work that well.  My cases aren't in good light; mine are in bad lighting.  I concede that I may be asking the camera to do something unreasonable.  Even with cross-type only points in AI Servo mode, even though the diver is closer to me than anything, down throughout the dive the AF point will still go back and hit the wall, for some unknown reason, at least twice.  The reason is because the wall is grayish/white and is lighted up more than the diver.  This will confuse any AF system.  To the OP, you have to pay attention to back-lighting too.

Good discussion so far.
I sometimes shoot golf with my friends, I got a tip from Bosman a couple of months ago to lock on the golfer and then switch to manual so the camera doesn't try to track the club or arms moving. This for your swim meet. I wouldn't dare to give you tips as you're a much more accomplished photographer, I'm more asking you if that would have been relevant in the swim meet? At least if you're shooting from the same spot. This is assuming you shot diving and not swimming.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 20, 2013, 05:27:55 AM
You can go to usa.canon.com and download the English version of the manual for free.

it seems like you forgot an IMPORTANT THING

pls review your manual at page 73 and page 77

61 point automatic selection AF both in A+ and AI Servo Modes

dont worry, there's nothing wrong with your 5D3, just wrong user settings. :)

we all experience it - one way or the other.
That was a very good suggestion. Now I can immediately find the things you all were talking about in the manual. Still no real sucess though. I hope to get out tomorrow with the camera and try some more.
Cheers Brian
Hi,
well I had far better results yesterday, despite pretty poor light. Still had a few shots I couldn't explain, 4 focus points on a slow moving car, but the car itself completely out of focus. But I even did get a shot of a flying duck in focus in pretty bad light, taken a bit by surprise too. Using 61 point auto-selection.
Never had the points on a bird in a sutuation like that up till now.
Cheers Brian

70-200 F2.8L IS II USM at 200mm, F6.7, 1000th/Sec, ISO800.
Title: Re: My never ending Focus woes with my 5DMK3
Post by: bjd on January 20, 2013, 05:39:06 AM
Hi,
well I had far better results yesterday, despite pretty poor light. Still had a few shots I couldn't explain, 4 focus points on a slow moving car, but the car itself completely out of focus. But I even did get a shot of a flying duck in focus in pretty bad light, taken a bit by surprise too. Using 61 point auto-selection.
Never had the points on a bird in a sutuation like that up till now.
Cheers Brian

70-200 F2.8L IS II USM at 200mm, F6.7, 1000th/Sec, ISO800.
And built this out of it. I guess my next Lens will be something with a 400 in it. 200mm doesn't go a long way.
Cheers Brian

Title: Re: My never ending Focus woes with my 5DMK3
Post by: jp121 on January 20, 2013, 11:31:59 AM
Hobby Shooter,

try 'back button auto focus' for the golfer. It saves switching to manual every time. Back button AF takes AF away from the shutter button. You can hit the shutter button all day with no AF. To re-AF press the 'back button'.
Title: Re: My (seemingly) never ending Focus woes.... BIF advice needed
Post by: bjd on March 02, 2013, 04:35:24 AM
Hi,
I have much more of a grip on how thinks should work and in many cases I do get them to work that way.
Tracking small Birds and getting them in focus is still not what I had hoped for so I am systematically trying to work through that now. That in itself is difficult, how should one do anything systematically with the little critters?
So, much of this has been said before, but I would like to discuss the points according to my experience at this time. Please bear with me :-\

So, I tried a setup where the birds can only fly across the FOV left to right to land on a feeding spot. And back out the same way. Using a Zoom is almost impossible here as the birds spend too little time in the field of view, plus DOF is in most cases just too shallow. So I'm currently trying with my 16-35.

I'm also planning a setup where the birds will fly more into the Camera instead of across it at 90°.

In the above case its impossible to put a focus point on the bird manually, I'm too slow for it. So I guessed that using 61-Point auto-selection is the way to go. I cant use AI Focus as I cant focus beforehand on a still subject, AI Servo requires a manually selected AF point beforehand too. So So IMHO it looks like one way is to use AI Servo and  a single point pushed over to the left and hope that that achieves focus straight away.

Now to the background,  I have trouble that the camera likes to focus on the background. I tried various sheets, but they provided a perfect target and the camera took them everytime. Apart from a proper backdrop, any tips here to provide something the camera wont focus on?

Comments?

Cheers Brian