Photographing dog agility with Canon 50D

[circa71]

<p>Okay, novice question of the day...<br>

I just upgraded to the Canon 50D from my trusty 20D, and I am perplexed by the AF On. Is that the equivilent of pressing the shutter button half way on the 20D to achieve focus? My auto focus works on it's own in the basic settings, but in the custom settings (which are what I try to use) nothing happens when I wake the camera up by pressing half way on the front button. Is that because I am supposed to use the AF On to focus? Sorry if this is a stupid question, but this has been quite a jump for me.<br>

I'm also wondering what the best setting/technique would be for capturing action...if the camera is set to AI Servo and for multiple high speed shots, am I holding the shutter button and the AF On to get it to focus while shooting a moving target? I feel like I've never used a camera before.<br>

Thanks in advance for any help or advice.</p>

[benjamindbloom]

<p>I have my 50D set up the following way:</p>

<ul>

<li>AI-Servo focusing </li>

<li>Use the AF-On button to initiate the autofocus system</li>

<li>Disable the half-press from affecting the AF system (it only calculates exposure.)</li>

<li>High speed burst mode</li>

</ul>

<p>The important piece is the custom function that defines what the AF-On button and Shutter Button do. I can't recall which function it is off the top of my head.</p>

<p>My shooting technique is to compose the shot where I expect my subject (runners/bikers/skiers for me, dogs for you) to be in a way that gives me a shot that I like. I then calculate my exposure (M or Av usually) and set my focus point accordingly. As my subject starts to get close to my desired location, I put the AF point that I set over my subjects head (if I'm shooting shallow DOF) or center-mass (if I'm shooting with a little deeper DOF) and roll my thumb onto the AF-On button. My thumb stays on the button as I track my subject and rattle off a few frames.</p>

<p>It works pretty well and gives me shots like these: http://sonicbloom.org/blog/?p=96</p>

<p>There are a number of tutorials online about using the thumb button to control focus and the shutter button to control exposure. It works for some and not others. If you want, you can ignore the AF-On button and configure you camera so that the shutter button controls AF and exposure. When I get back to my camera tonight, if you're still confused, I can find the exact custom functions that work for me.</p>

<p>Dog agility should be a fun challenge! Be sure to share some of the shots!</p>

[circa71]

<p>Thank you so much! I loved your runner shots, (and your portraits are wonderful). I would love to know the settings that work for you, if it isn't too much trouble. To tell you the truth accurate focus has always been an issue of mine, and perhaps it would be best for me to learn some new techniques and stop relying on the basic AF as much. I am interrested in how to configure the camera so that the shutter button controls AF and exposure, though. Do you know where I would change that setting?</p>

 

[hughes]

<p>Jennifer<br>

there is another way I just photographed a dog agilty event and used manual focus and single shot for many shots I am a bit of a Luddite and still tend to use my digital Nikon like it's an old FM I prefocus on a certain point and take a single shot when the subject gets to that point, actually timing is everything so you press the shutter just before thay get there.<br>

Here are a couple of examples now I'm not saying this is what you should do but it is possible to get some good shots without usng AF if using AF and burst mode isn't cutting it<br>

Steve </p><div></div>

[hughes]

<p>another</p><div></div>

[benjamindbloom]

<p>Hi Jennifer,<br>

So in looking at my camera. If you go to Custom Function IV, #1 there are five options (0-4) This custom function sets what the two buttons do: Shutter button / AF-on button. I have mine set to 3, where the AF-On button starts metering and starts the autofocus, but when I half-press the shutter button it locks the exposure. That works pretty well for me.<br>

If you have it set to 0, the shutter button controls AF and exposure and you can completely ignore the AF-On button - it is disabled.<br>

I think with either setting, what's important is that YOU set the focus point - don't let the camera decide what it wants to focus on. Sometimes that will work great, but you'll get more reliable and accurate autofocus by setting the AF points yourself. I have my camera configured so that I can hit the right-most thumb button and spin the back dial OR I can use the joystick to set my focus point where I want it. (The only reason I have both is for when I have a battery grip attached.)<br>

Steve also has good advice in prefocusing on where the action is and snapping the photo at the critical moment. </p>

<p>-Ben</p>

[michelle_gifford]

<p>absolutely loving the dog shots!!</p>

[hughes]

<p>I sincerely apologise for the lack of punctuation in my previous post, I would like to blame a combination of too much coffee and too much haste, either way I stand corrected.<br>

Steve</p>

[circa71]

<p>Thank you everyone! I'll post some shots soon, but I've been playing with a couple of different focus methods, and think I'm starting to get the hang of it. I got it back to full autofocus mode, and found I missed the use of the rear AF On button. It makes me happy it was set like that when I got it. I always assumed the camera would focus best, but now I'm finding my own eye (and finger) are more reliable).<br>

And Steve, don't ever apologize for too much coffee! ;)</p>

[circa71]

<p>Those dog shots, are inspiring, by the way!</p>

[amin_siminati]

<p>More dog shots would make this thread alot more interesting. </p>

[rik_janson]

<p>For a shot like this where you know where the subject is going to be, then yes, manually focusing and waiting for the subject to arrive works well. However, I, too, would love a good solution for focusing on kids or free-running dogs who are coming straight at the camera on an unpredictable path (5D Mark II, 70-200 F/2.8L II IS USM).<br>

<img src="http://rickjanson.smugmug.com/Events/Denver-Polo-Classic-2011/PoloPonies/i-BrnBcT6/0/M/Dog8714-M.jpg" alt="" /><br>

F/4.5, 1/2000 sec, ISO-100, 145 mm, 7.1 meters.</p>

[acedigital]

<p>I would also suggest you activate the Center Focus point and use AI Servo (tracks moving objects).<br>

Today's AF systems are pretty advanced, I can't see the need to use manual focus, but to each his/her own.</p>