Focusing Questions for 1DMkIIn and 50D

Hey everyone. So I recently picked up a 1DMkIIn and have been shooting quite a bit of soccer with it. I have been using the back button to focus Custom Function as I used to do with my 50D. Now my question is, why is it that I get far more keepers with depressing the shutter halfway as opposed to using the back button to focus technique? I know it could be user error, but I find that on a consistent basis whenever I use the back button to focus I seem to get far more throw away pictures that are not tack sharp.

Any ideas? Thanks.

I switched mine from back button focus to shutter button too. Same reason. I see good uses for using the back button, but not in what I shoot.

I have never been a fan of back button AF myself. To me it makes it harder to shoot (I am terrrible at multitasking), which may in fact be your problem. It gives you more opportunity to shoot without achieving focus

So does back button solely rely on the eye of the photographer to be sure that the subject is sharp in the viewfinder before taking the shot?

I have my thumb active the whole time while I pan with my subjects, but it just seems like I have more of a "feel" for my shutter button with the halfway down method of AF.

I am perplexed even more because so many Sports photogs say that back button is the only way to go but I cannot figure out why. But I do not find that I lose any shots when I do the half method.

To put this all together so far, half down achieves focus lock and back button doesn't?

I've only played around with the back button for focusing a few times.. I find the shutter button quicker and easier..

The mechanics of focusing in the camera are the same, regardless of how you trigger the focus.
If you just keep the button pressed, AF-ON or half-press or whatever you use, then there's no difference at all, from a technical point of view.

The advantage I see with using AF-ON is that I can momentarily interrupt focusing, but still take pictures, if I see that something (bushes or whatever) are interfering with the focusing. If I'm following a runner who goes behind some bushes, I can just stop Servo AF from running while the runner is behind the bushes. Since the runner is in focus, but the bushes aren't, I can still take pictures that make sense, if I like. And I'm ready to continue as soon as there's a clear line of sight again.

There aren't many bushes on a football field, but there are other people, so the principle is the same.

Probably you aren't getting along with holding the camera in a way where you can easily operate the focus button and take pictures at the same time, so it's you who mess up subject tracking, and thus focus.
I don't use back button for certain subjects either. Around the house snapshots work better with everything on the shutter button.

When shooting action I have both AF-ON and * active for focusing, one with the selected AF point, the other with the registered point (HP, Home Point). Like in the situation below, where I used a focus point a bit to the right in the viewfinder for photos of cars going to the left, but a point a bit to the left when they've turned around in the hairpin and moved to the right again. Just moving my thumb between AF-ON and * made the selection easy.

Should I need AE lock, I have that on M-Fn.

The heavily reduced size of the image below makes both cars look like they are out of focus, but the one I aimed at actually is sharp. It's better here.

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Hey apersson, what camera do you have? I don't think I can have the AF-ON AND the * button active for focusing, it's one or the other on the 1D Mark III.

BIFF, the * button for focusing in AI-Servo is the only way to go for shooting cycling. You just need to get used to it. Once you do, you'll never go back. I have mine set up where * activates AF and exposure is set upon pressing the shutter. That way if a cyclist moves in and out of shadows, he'll still be properly exposed. The other option would be to have AF initiated with * AND have exposure locked with *. That doesn't work to well with cycling.

I suggest both of you read this: http://www.usa.canon.c​om …ArticleAct&arti​cleID=2286

With back button focusing, pressing the shutter button at ANY time should take the picture, especially if you have drive priority set to drive, not focus. This means the shot may be out of focus but you'll get 8.5 fps guaranteed. With drive priority set to focus and using the shutter button it will wait for focus to be achieved even with AI SERVO which may slow it down but may give you more keepers in the end. Just depends what you want, the shot at that moment no matter what or more shots in focus. Personally, I'd rather have the shot at that time of my choosing but your mileage may vary.

Oh, and with cameras that have the AF-ON button you can take AF away from the shutter button and you can swap the AF-ON and * button functions but you can assign AF to both AF-ON and *. In the Mark II and classic you can have the * button AND the focus assist button (what turned into the AF-ON button in the Mark III) do AF with the main (*) and registered (assist) AF point. Really cool, actually a feature I miss on the Mark III. On the mark III I don't think you can immediately AF with either the main or registered point like that. The 7D lets you assign the registered point to do the same thing as the Mark II/Classic.

ajaffe wrote in post #10833188
Hey everyone. So I recently picked up a 1DMkIIn and have been shooting quite a bit of soccer with it. I have been using the back button to focus Custom Function as I used to do with my 50D. Now my question is, why is it that I get far more keepers with depressing the shutter halfway as opposed to using the back button to focus technique? I know it could be user error, but I find that on a consistent basis whenever I use the back button to focus I seem to get far more throw away pictures that are not tack sharp.

Any ideas? Thanks.

Single shot or AI Servo?

It sounds like you need to work on the technique more.
By separating the AF function from your shutter, as you may know, you open a new world of options in how you lock exposure, and lock focus before pressing the shutter release.

However, these same options do mean that you may not still be in focus when you press the shutter if your technique is off..

ajaffe wrote in post #10834004
...

To put this all together so far, half down achieves focus lock and back button doesn't?

No, they both achieve AF lock..

ajaffe wrote in post #10834004
....

I am perplexed even more because so many Sports photogs say that back button is the only way to go but I cannot figure out why. But I do not find that I lose any shots when I do the half method.

...

It sounds like you are using the * button to AF without really understanding the technique yet..

In the long run, I am one of the many that suggest this technique as a way to get by far the best from your DSLR,. so your patience in trying to work this out will pay off, again in the long run, if your persevere.

Take a moment to read/skim through this thread,.
It gets repetitive, but essentially it is this same discussion we are having now, combined over and over into one thread on this subject;

https://photography-on-the.net/forum/showthre​ad.php?t=46965

You will find a lot more info there than you will waiting for us all to repeat ourselves again here.

If you have focus set to shutter button:
in oneshot the camera will not trip the shutter until AF is achieved
in AI servo/burst shutter mode the camera will allow the first shot to be OOF, but won't allow the second and consecutive shots to be OOF. EXCEPT if you set the custom function in the 1 series to keep shutter priority

with the * or af-on button focus, the camera will allow you to take a shot without the subject being focused at all. So, it is possible you are either not holding the button down or are tripping the shutter before AF is locked on

timbop wrote in post #10838234
If you have focus set to shutter button:
in oneshot the camera will not trip the shutter until AF is achieved
in AI servo/burst shutter mode the camera will allow the first shot to be OOF, but won't allow the second and consecutive shots to be OOF. EXCEPT if you set the custom function in the 1 series to keep shutter priority

Actually that custom function sets the time allocated to focusing between each shot. For drive priority it's essentially the lens drive time, since that's the theoretically shortest time in which focus can be accomplished, provided the AF sensor gets a good reading immediately.

If it doesn't, the image will not be within focus, and that's regardless of whether it's ther first or later images.
Now in AF priority, the allocated time for the focusing operation is longer, but it's still limited. If focusing has not completed when this longer time has passed, then the camera will indeed take out of focus images in AF priority as well.
During normal conditions, you don't notice any difference.
Only 1D series and the 7D have these advanced AF settings. Other cameras are always in AF priority.

My camera is a 7D, and there you can set all buttons regardless of all other buttons, so there are no commands like "swap one button with another". You just allocated functions to a button, without having to look at other buttons at the same time. You can for example assign AE lock to four different buttons simultaneously.

The best way to take pictures is if the AF and shutter functions are completely independent of each other, so that neither can screw the other up. It took me a while to get the hang of it, but enough professional sports photographers who I respect convinced me to give it a try. Once I got used to it (and it took a while), I found it to be the superior method. That doesn't mean it will work for everyone, but it can take a while to get used to it.

I went out today and did some work for the school paper. All done via back button focus. All tack sharp.

I think my issue is that I get sucked into the game and "force" my shots instead of letting them come to me.

I essentially use AI servo on high speed continuous and rip off maybe 2-4 shots per sequence starting at the beginning of the action.
I notice that I sometimes let go of the back button and as a result the subject will move out of focus enough which will make it a soft image correct?
So to fix this I just need to keep my thumb on the back button and keep the button depressed while I shoot my sequences?

Also, do I have to wait until the little green light comes on in the viewfinder to tell me I am focused before I shoot? Or is this something that my eyes will tell me over time? (which worries me because I have really crappy eyesight)

Yes, when the * button is used for focusing you must hold it down the entire time which takes some getting used to. If you let go it will stop focusing but the shutter button will still take shots, out of focus or in focus.

I find my son's games can be bad, I get involved in it and miss shots. When I'm shooting teams I have no involvement with, it is much easier to be neutral and just shoot the game without getting caught up in it.