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Photo Forum / Digital Photography / DSLR Cameras / February 2007canine action photography - few tips needed
Hi, can someone pls tell me what is the best way to photograph a dog that is running straight toward me. I want his head to be in focus and body slightly out of focus. Equipment is Canon EOS 400D XTi, lenses Canon EF 70-200mm L USM. What I did today was to set autofocus to AI servo, set AF point to most upper, TV mode - shutter speed to 1/640. When dog was running toward me, I aligned selected AF point with his head and took photographs. And they were not what I hoped for to achieve. His body was in focus but head was out of it. As if autofocus had a lag. Weather was cloudy and dog is light gray. Maybe on a sunny day results would be different but I'm puzzled how to solve this problem. Maybe to keep shutter button half pressed would help tracking or something? > Hi, can someone pls tell me what is the best way to photograph a dog that is > running straight toward me. I want his head to be in focus and body slightly [quoted text clipped - 9 lines] > be different but I'm puzzled how to solve this problem. > Maybe to keep shutter button half pressed would help tracking or something? For the "predictive" AI to work, you do need to keep the shutter button activated so that the focusing can track the movement. Otherwise, it doesn't activate until you depress the shutter button, by which time (if you're making a "full" depression of the butter in one motion) it can't "predict" the movement, and the object is past the focal point by the time the shutter activates. Also, you need to make sure you are in "AF Servo" mode. See your manual, pg. 56. Another tip is to separate the focus from the shutter button. You can do this with Custom Function 4, setting it to AE Lock/AF mode (see pg. 104). Then, the * button becoms your focusing button (use your thumb on it, your finger on the shutter), and you can focus with it without fear of accidentally pressing the shutter button too hard while tracking and snapping the pic at the wrong time. It takes a little getting used to, but this is the mode I generally leave my camera in, because I can focus independently of the shutter button if desired, so I can focus and recompose without having to keep my finger halfway down on the button - otherwise, it would refocus (or I'd have to be in manual focus) every time I go to press the shutter.  SignatureYou need only reflect that one of the best ways to get yourself a reputation as a dangerous citizen these days is to go about repeating the very phrases which our founding fathers used in the struggle for independence. -- Charles A. Beard > Hi, can someone pls tell me what is the best way to photograph a dog that is > running straight toward me. I want his head to be in focus and body slightly [quoted text clipped - 9 lines] > be different but I'm puzzled how to solve this problem. > Maybe to keep shutter button half pressed would help tracking or something? Here's one idea: manually focus on a spot on the ground then click when the dog's face reaches that plane. If it's not already obvious, use 200mm f/2.8 for shallowest DOF. Also you may need a 1dM2 or similar pro model to get fast enough tracking of an animal running toward you and the XTi may not be up to the task. Test the settings by panning the camera around & listen to the AF motor to see if you got it right. I shoot Nikon so can't help on the exact settings for your camera. >Hi, can someone pls tell me what is the best way to photograph a dog that is >running straight toward me. I want his head to be in focus and body slightly [quoted text clipped - 9 lines] >be different but I'm puzzled how to solve this problem. >Maybe to keep shutter button half pressed would help tracking or something? Maybe. Or forget autofocus. Manually focus on a certain distance, press the shutter when the dog gets there. Alternatively, use your complete system, not just the camera. Go for more depth of focus, Photoshop the out of focus effect. It may not be exactly the SAME effect as camera focus. But it may be a useful effect. > Hi, can someone pls tell me what is the best way to photograph a dog that is > running straight toward me. I want his head to be in focus and body slightly [quoted text clipped - 9 lines] > be different but I'm puzzled how to solve this problem. > Maybe to keep shutter button half pressed would help tracking or something? What kind of dogs are your trying to track? Many running dogs are too fast for even high end cameras to track. I use a 1D Mark II set on high speed AI and these dogs can run faster than the camera with L-lenses: http://www.clarkvision.com/tmp/dogs Does the 400D have a custom function to boost the AI servo speed? (The 1D Mark II does.) If so set it to the higher speed. In general, use the fastest exposure times possible: shoot in Av mode with aperture at widest level, then adjust ISO as needed to get the frame stopping action. Roger Photos at: http://www.clarkvision.com > What kind of dogs are your trying to track? > Many running dogs are too fast for even high end cameras > to track. I use a 1D Mark II set on high speed AI and > these dogs can run faster than the camera with L-lenses: > > http://www.clarkvision.com/tmp/dogs With a RebXT and a 100-400, I was able to use AI servo to track Jack Russel terriers coming straight at me during a lure-coursing race quite well - even while backing off on the zoom as they approached - but was shooting at f/8, so my DOF was forgiving. Whenever I've been tracking a dog and had AI-servo fail me, it's always because at least one of two factors was present: One, the dog was moving erratically rather than at a semi-steady pace, two, my DOF was quite shallow. The AF mechanism in the XTi being faster than that in my camera, and the fact that he has a lens with good, fast AF, I would be surprised if he weren't able to get much better pictures with just a little practice. As for the suggestion of others to pre-focus on one spot and shoot when the dog reaches it, I wouldn't bother with that. You typically want to catch the dog at a certain point in its stride, and I'm not aware of any dogs which will make sure to hit that for you at a predetermined spot.... :-) That method works well at things like agility or flyball competitions, where you know that going over a jump, coming out of a tunnel, or bouncing off of a wall that they *will* be in a good stance in a certain location, but if they're running, it's up to you and your timing. steve >>What kind of dogs are your trying to track? >>Many running dogs are too fast for even high end cameras [quoted text clipped - 7 lines] > well - even while backing off on the zoom as they approached - but was > shooting at f/8, so my DOF was forgiving. Ability to track is purely a function of how large the subject is in the frame, and speed and acceleration of the subject. It is easy to track a subject when small in the frame, so the rate of change in the focal plane is small. For that same velocity, if the subject fills the frame, the rate of change in the focal plane is higher. In the example images on the above web page, the first image is full frame height and at that velocity, the dog was a challenge for a 1D Mark II. The third frame, 2 dogs running in snow, has a much lower focal plane rate and would be easy for a 1D Mark II (it was taken with a 10D). The 100-400 L IS lens is relatively slow AF. The 70-200 is faster (I have both), but I prefer 300 f/4 L IS and the 70-200 for such action. > Whenever I've been tracking a dog and had AI-servo fail me, it's always > because at least one of two factors was present: One, the dog was moving > erratically rather than at a semi-steady pace, two, my DOF was quite > shallow. I would like to know more, as this is not my experience with top (1D) cameras and top lenses for frame filling subjects. Are you referring to frame filling subjects? This is also not my experience with birds (frame filled images): http://www.clarkvision.com/galleries/gallery.bird Smaller birds move so fast that even 1D cameras can't respond fast enough in my experience. > The AF mechanism in the XTi being faster than that in my camera, and the > fact that he has a lens with good, fast AF, I would be surprised if he > weren't able to get much better pictures with just a little practice. Could you post some uncropped examples? > As for the suggestion of others to pre-focus on one spot and shoot when > the dog reaches it, I wouldn't bother with that. You typically want to [quoted text clipped - 4 lines] > off of a wall that they *will* be in a good stance in a certain location, > but if they're running, it's up to you and your timing. I agree. Roger >> Whenever I've been tracking a dog and had AI-servo fail me, it's always >> because at least one of two factors was present: One, the dog was moving [quoted text clipped - 4 lines] > top (1D) cameras and top lenses for frame filling subjects. > Are you referring to frame filling subjects? Not usually frame-filling. I only shot the one lure-coursing race (as a favor to a friend), and evidently the way to sell photos at that is to include the whole "pack", so that the owner of the dog in the lead will see that their dog was the fastest. :-) That was with the 100-400, the distances (and small dogs) were too much for my 70-200 f/2.8. When it's an individual dog, I usually fill the frame a little more, but still - if it's moving straight at me and at a fairly constant pace, I can usually make it work out - particularly if my DOF isn't too shallow. If the dog isn't running in a straight line, then things get a lot tougher. > This is also not my experience with birds (frame filled images): > http://www.clarkvision.com/galleries/gallery.bird > Smaller birds move so fast that even 1D cameras can't respond > fast enough in my experience. Small birds are like little ADD-sufferers on crack, meth, and a good cup of coffee to boot! My understanding is that AI-Servo is designed for objects moving more or less right at the camera (surfers, race cars, etc.), and while I've only shot one bird picture in my life, it doesn't seem like that describes their movement very often. >> The AF mechanism in the XTi being faster than that in my camera, and >> the fact that he has a lens with good, fast AF, I would be surprised if >> he weren't able to get much better pictures with just a little practice. > > Could you post some uncropped examples? I did just a quick glance through some dog photos, and while these two aren't the most artistic photos (or even that interesting), I thought they were a decent example. They're two consecutive shots, using AI-Servo and my 70-200 f/2.8. There were a couple of others where the focus wasn't on the dog's head, but I'm not sure if that was from me not tracking well, the camera not tracking well, or the dog not moving at a steady pace: http://codon.com/ai-servo/1420.jpg http://codon.com/ai-servo/1421.jpg And here's one I wouldn't have been able to capture without AI-servo, she was at a fair trot for this one: http://codon.com/ai-servo/mr.jpg My understanding (which could be wrong) is that AI-Servo is specifically designed for objects moving right at the camera steve > I did just a quick glance through some dog photos, and while these two > aren't the most artistic photos (or even that interesting), I thought they [quoted text clipped - 5 lines] > http://codon.com/ai-servo/1420.jpg > http://codon.com/ai-servo/1421.jpg I think these photos illustrate the differences in our experiences. The dog appears to be in a trot or fast walk, not a full out run. Try your AI servo when the dog is running at top speed toward you and fill the frame (in your above example, vertical would have been nicer). Then you'll see the AI servo fail to keep up with tracking. > And here's one I wouldn't have been able to capture without AI-servo, she > was at a fair trot for this one: [quoted text clipped - 3 lines] > My understanding (which could be wrong) is that AI-Servo is specifically > designed for objects moving right at the camera Not quite. The tracking tracks the focal position and predicts the focal position at the time of shutter firing based on the velocity of the focal position. The subject can be moving diagonally and the servo tracks the relative velocity toward or away from the camera. The subject does not need to only go toward or away from the camera. In fact, off-axis velocity means the relative speed toward or away decreases as the cosine of the angle off-axis. The challenge in any case is for the photographer to keep the subject on a focus point. Here is an example of the subject, an Alaskan brown bear diving, where the axis of velocity is about 30 degrees from straight on, and the camera did a good job: http://www.clarkvision.com/galleries/gallery.bear/web/brown_bear.c09.07.2004.JZ3 F0862.b-700.html Roger > I think these photos illustrate the differences in our experiences. > The dog appears to be in a trot or fast walk, not a full out run. > Try your AI servo when the dog is running at top speed toward you > and fill the frame (in your above example, vertical would have been > nicer). Then you'll see the AI servo fail to keep up with tracking. Right after I sent that, I realized that I didn't post images from the lure-coursing event. I wasn't filling the entire frame (Jack Russells at 50 yards are pretty small, even for a 400mm lens on an APS-C body), but at f/8, I was able to track them running nearly directly at me - while backing off on the zoom as well, and I don't recall any missed-focus shots. There were a few where I let the AF point drift to a different dog, but that was my error. Looking through the shots, as the dogs approached me and the small pack of five filled more of the frame and the DOF got more shallow, the lead dog was still in focus in virtually every shot, even when the rear of the pack (just a body length behind) weren't. There is a big difference between a weimeraner and a jack russell, but I was still amazed at how fast those little dogs were. I was picking my shots, not bursting away, and perhaps that had something to do with it - but even in one situation where a dog "crashed" over a hurdle, in a burst of three shots (at my "measly" 3 FPS), you see the dog crashing in the first shot, landind upside down in the next shot, and almost back on it's feet in the next shot, before the dog in second place had a chance to close the gap - and he's in focus in every one. If I had been using my 70-200 at f/2.8, even with the faster AF, I wouldn't expect it to do nearly as well - the DOF would simply be too shallow and unforgiving. >> My understanding (which could be wrong) is that AI-Servo is >> specifically designed for objects moving right at the camera [quoted text clipped - 4 lines] > servo tracks the relative velocity toward or away from the camera. > The subject does not need to only go toward or away from the camera. You're right, but you're missing my point - you said that AI-Servo didn't track birds well, and I said that birds don't tend to move in the way that AI-Servo works well with. I usually see them in jerking, irregular motion (although there is some difference between the predator and prey birds), which really throws off AI-servo. A running dog is much easier for ai-servo to track. I haven't done much shooting lately, but the next time I get a chance, I'll take some shots of dogs at a full-run. I know a place where I can find off-leash weimeraners, greyhounds, and just about everything else, so it'll give me a chance to really put it to the test. steve >> I think these photos illustrate the differences in our experiences. >> The dog appears to be in a trot or fast walk, not a full out run. [quoted text clipped - 40 lines] > which really throws off AI-servo. A running dog is much easier for ai-servo > to track. AI servos fail for (at least) 3 reasons: 1) velocity of the focal plane shift is too high to track. This is a function of velocity of the subject, focal length of the lens, and distance to the subject. Frame filling subjects are the most difficult. I've been working on a web page describing this. 2) Acceleration of the subject. AI assumes linear velocity. 3) Not smooth enough tracking by the photographer. If the photographer is panning but the pan is not smooth, the focus point wanders over the subject, thus different distances to the subject, effectively accelerating the focus point. In the worst case, the focus point slips off the subject and onto the background, so focus goes way off. When I said AI does not track birds well, I think I remember saying small birds. Their flight velocity is simply too fast. Birds landing or taking off are accelerating, thus it is difficult for AI to track, e.g.: The great egret was accelerating at takeoff: http://www.clarkvision.com/galleries/gallery.bird/web/c01.14.2003.img_5113.egret -flight.f-600.html Here are a lot of flight shots of birds: http://www.clarkvision.com/galleries/gallery.bird I have tens of thousands of bird flight images. My experience with birds, dogs, and other animals, from lions to cheetahs, to bears to zebras in the wild, all can run (birds fly) in zig-zag or linear motions depending on what the situation is. > I haven't done much shooting lately, but the next time I get a chance, > I'll take some shots of dogs at a full-run. I know a place where I can find > off-leash weimeraners, greyhounds, and just about everything else, so it'll > give me a chance to really put it to the test. I have done a lot of shooting lately. For example, I just returned from Africa shooting a lot of action; over 8,000 images. If you really can get frame filling sharp images, please teach us all, because on many subjects I and my equipment (1D mark II--the fastest camera on the market) fail in high velocity situations. Latest Africa images: http://www.clarkvision.com/galleries/gallery.africa Roger > What kind of dogs are your trying to track? A weimaraner, it's a big, fast dog. Quite a challenge, I'd say. > Does the 400D have a custom function to boost the AI servo > speed? No, it has not. Only one AI servo speed. Thanks for all the tips. Prefocus and shoot technique would definitely give results but I'd prefer to have camera track dog's head. Waiting for a nice, sunny day to test it all, weather outside is bad right now. Pante >> What kind of dogs are your trying to track? > [quoted text clipped - 11 lines] > > Pante These situations are ones that I always could do with film, but have problems with digital. This is where I would get my trusty old 35mm and shoot manually...:-) I would probably use as shallow DOF as possible for the lighting and manually focus. I still use manual focus on digital with the exception of some high volume shoots mainly at sporting events. Just an old habit that is tough to get rid of. I used all Pentax film equipment and went Pentax for digital too so that I could still use all my old 'A' lenses. Ed On Feb 10, 6:26 am, "Roger N. Clark (change username to rnclark)" <usern...@qwest.net> wrote: > Does the 400D have a custom function to boost the AI servo > speed? (The 1D Mark II does.) If so set it to the higher > speed. Now that's interesting. What advantages would lowering the servo speed have? Or, what disadvantages would a high-speed servo have? > On Feb 10, 6:26 am, "Roger N. Clark (change username to rnclark)" > <usern...@qwest.net> wrote: [quoted text clipped - 5 lines] > Now that's interesting. What advantages would lowering the servo speed > have? Lower power. Or, what disadvantages would a high-speed servo have? Higher power. |
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