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09-14-2007, 10:00 PM   #61
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Auto-focus Is Never Infallible.

QuoteOriginally posted by GaryML Quote
(snip) I am seriously considering investing in a different system with superior AF performance. (snip)

The auto-focus system is an aid to humans, not a replacement. Regardless of the camera brand (Canon, Pentax, etc) or mechanism type, there will always be situations where auto-focus fails in some regard. That is exactly why manual focus still exists. When something doesn't work (auto-focus or whatever), the solution for most people is to switch tactics and learn a new skill instead of running out to buy a new camera. Manual focus is just one of those many new skills one can learn.

Many advanced photographers feel the same way about auto-focus as they do about point & shoot exposure modes, in-camera image adjustments, and similar automation - these are a convenience, but I can do better in most situations. Therefore, they tend to avoid automation entirely. However, I think the solution is somewhere in the middle of the two extremes of totally depending on automation or totally avoiding it. Automation can be enjoyed when it works as long as one isn't afraid to try something else when it doesn't.

Since many of the larger lenses used by the pros for sports will not auto-focus with most cameras, using manual focus for sports isn't exactly that unusual today. Of course, most of these photographers will immediately tell you that photographers were taking great sport images long before auto-focus even existed.

stewart

09-14-2007, 10:49 PM   #62
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QuoteOriginally posted by smcclelland Quote
Looking good man! A quick side note for any panning shots you might want to experiment with starting at 1/250 and working down as 250 will still give you some nice background blur and if you can knock it down to the 1/125 range or lower you'll get some awesome effects Photo looks nice and sharp, the 50-135 is a superb lens and I'm sure the SDM probably lends a nice helping hand with the AF-C.

Keep up the great work Gary, look forward to seeing more test shots and seeing how your sports shooting develops

-s
Thanks. The DA* 50-135mm is deserving of the "*" designation and the SDM got quite a workout today. I will try some of the blurred motion panned shots when I get a chance.


QuoteOriginally posted by stewart_photo Quote
The auto-focus system is an aid to humans, not a replacement. Regardless of the camera brand (Canon, Pentax, etc) or mechanism type, there will always be situations where auto-focus fails in some regard. That is exactly why manual focus still exists. When something doesn't work (auto-focus or whatever), the solution for most people is to switch tactics and learn a new skill instead of running out to buy a new camera. Manual focus is just one of those many new skills one can learn.
I did a test shot with the kids running laps and running straight at me. With either AF-C or AF-S, the camera simply didn't adjust fast enough and the focus point was consistently about a foot behind the intended target (basically the kid behind the kid who should have been in focus). This was with the SDM lens and so it isn't a defect in my Sigma lens. It simply reflects the lack of an effective focus prediction feature in this specific application. I think other systems (e.g., Canon and Nikon) may do better, but for the short term at least I understand the limitation and will adjust my position on the field relative to the action to accommodate it. I think this was the main problem earlier in the month, as I was mostly behind the goal box with the kids running at me.

I agree with your comment to a certain extent. Manual focus can be used in situations where auto-focus isn't reliable. But in this situation, I was really hoping for AF to help and I bought the fairly expensive Sigma lens for this purpose. I have read quite a few magazine articles and books where professional sports photographers discuss their technique. Some do pre-focus manually where they think the action will be and wait. But others have success with the AF system following the action, using the high-end Canon equipment. While the professional Canon stuff is beyond both my budget and the lifting capacity of my back, I was curious if the mid-level equipment would do better than my Pentax. I think the answer is yes, but I also think a good solution is to adjust my technique to get good results with the equipment I have.
09-15-2007, 02:17 AM   #63
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Hey Gary - wouldn't it just be so cool to be able to afford BOTH for a while to give them a good try out? Damn, forgot to buy my lottery ticket this week!
09-15-2007, 03:15 AM   #64
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QuoteOriginally posted by GaryML Quote
I did a test shot with the kids running laps and running straight at me. With either AF-C or AF-S, the camera simply didn't adjust fast enough and the focus point was consistently about a foot behind the intended target (basically the kid behind the kid who should have been in focus).
Were you using automatic focus point, or select/center? I found that I got much higher hit rates using automatic, it did fairly well at hitting the moving target. Of course you'll still get the shots where it hit the wrong target, but thats sometimes better than being totally out of focus

09-15-2007, 09:18 AM   #65
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QuoteOriginally posted by Maxington Quote
Were you using automatic focus point, or select/center? I found that I got much higher hit rates using automatic, it did fairly well at hitting the moving target. Of course you'll still get the shots where it hit the wrong target, but thats sometimes better than being totally out of focus
Yesterday I used auto-select the focus point for the whole day, and mostly AF-C but also tried AF-S. I think that this does help me a bit.

I would focus on the line of kids running towards me. I hear the focus confirm beep, see the red square on the target, and shoot. And when I examine the photo, the focus was behind the subject. I intentionally used a wide aperture so I could see the focus plane clearly. The AF simply couldn't keep up. (And before anyone raises the issue, I was focusing on the kids way down the line and nowhere near the minimum focusing distance of the lens.)

The upshot of this is that the K10D AF system can't handle this particular situation very well, even with the SDM lens. I can compensate by planning my shots so that the kids are running sideways within the focus plane or are relatively stationary for a second or two. By moving from my old position in the end zone to the sidelines, I can get many more shots in focus using AF. Eventually, I may get a camera with better predictive AF.
09-15-2007, 11:14 AM   #66
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QuoteOriginally posted by Arpe Quote
Hey Gary - wouldn't it just be so cool to be able to afford BOTH for a while to give them a good try out?
That would be nice. Maybe the Nikon 200-400mm f/4 plus a D300. All I need is an extra $7000!
09-15-2007, 12:25 PM   #67
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Your findings about continous focus are in line with what I would expect. Are you still planning on borrowing or renting a canon setup to test the difference? It would be interesting to hear how much greener the grass on the other side is.
09-15-2007, 04:58 PM   #68
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QuoteOriginally posted by and Quote
Your findings about continous focus are in line with what I would expect. Are you still planning on borrowing or renting a canon setup to test the difference? It would be interesting to hear how much greener the grass on the other side is.
I did more testing today and the DA* 50-135mm f2.8 SDM lens is definitely faster focusing as compared to the Sigma 100-300mm f4. Part of it may be the f/2.8 speed, but the SDM system seems faster and more accurate.

I am still uncertain of what the best set-up would be. Based on my experience today with the DA* 50-135mm f2.8, I'm beginning to think that something with a slightly shorter focal length but f/2.8 aperture may be more usable. I'm thinking about the upcoming Pentax SDM DA* 200mm f2/8. I don't think I can afford any 300mm f2.8 with an in-lens motor. If I switch to Canon or Nikon, I may try to rent before I buy. But at this point, I'm not sure what I want to do.

09-15-2007, 07:53 PM   #69
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FWIW, the Canon 1D is capable of doing what you expected. A 1DmkII user was griping about the crappy autofocus of the new 1DmkIII and posted up a series of shots of a kid running down the line towards him towards 1st base and expected every single shot to be in focus and all of them were w/ the mkII but not the mkIII. I was amazed something like that would even work.

So it sounds like renting a Canon would be worth it. Pentax really needs a firmware setting that only allows shutter firing to happen in AF-C if it's locked...and improve their AF predictive logic...
09-16-2007, 05:05 AM   #70
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I would expect more from the Canon 1D as it costs a ton more money than the Pentax. I think one of the reasons that sports people tend to go with Canon 1D's is because of their AF and super fast exposure speeds. But you pay for it. It's a nice cam and wish I could afford one. With my K10D I do sometimes get frustrated shooting in-flight birds but I also get some good shots. I think you definitely need fast glass. My long zoom is a Sigma 50-500 which is about f/6.7 at 500mm so it is going to be slower. Nice shots can be had with practice though.
09-16-2007, 06:11 AM   #71
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I may have to disagree with the general direction this thread is going.

I think nobody will argue that Canon and Nikon have a better AF system.

You do not need an 8000 dollar camera to reap the benefits. I have both the K10D and a Canon 20D. The Canon is far better in the AF department.

I also have the Bigma with a Canon mount. I am also aware that the Pentax variant does not have HSM. I have found that the Bigma with HSM is a delight to shoot. It is fast, predictable, and accurate. So much so that I often do not bother with continuous AF. I can shot birds in flight in single AF mode with no problems. This is all with a Canon 20D. I hear the 40D has improved AF over the 20 and 30D models. Not sure how much better though.

With the Pentax K10D, I do not have the Bigma, but I do have a Tamron 70-300mm lens. I have found a general minor difficulty in getting birds in flight. It is not just that the AF is noticeably slower, but its behaviour is not as good. I suppose if all I had was the K10D, I wouldn't notice it as much, but with the Canon alongside it...it is very noticeable just how different the performance level of the two actually are. This difference would still be there if you were to shoot a Canon XT or XTi. You do not need to focus on the pro level cameras to compare them to the Pentax bodies when it comes to AF.

With that said, the new DA* lenses have faster motors in the lens, so that will help in speeding up the mechanical sides of things. This does not help the software side of things however, and this is where I feel Pentax needs to focus more resources on, to remain competitive with sport and wildlife shooters.

Lets face it, you can manual focus anything and be very successful. Auto focus comes into its own if you’re shooting unpredictable fast moving objects however, as you may only have a few seconds to capture your subject. So although I love the K10D, when it is time to do wildlife, I always grab the 20D.

Some more examples taken with the 20D and Bigma. A collection of Gull shots.









09-16-2007, 07:10 AM   #72
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I agree with chako, I guess also in the speed of single af, but mainly the biggest gap is in continous af, the pentax implementation in camera is not as good with moving subjects, the system does not seem to clever and doesnt react that fast. There is a lot to improve there. Altho speed and sports shooting is I feel the generally weakest point in the current Pentax models, not only the AF speed but also the fps is slower than the canikon offerings, so I just guess this isnt a big priority for pentax its hard to become the sports shooters choice if all of the sports shooters have already settled for canikon. I believe pentax will improve this especially if they release an above-k10d model, but I doubt that will be a speed focused camera with lots of fps and advanced af system.
09-16-2007, 08:52 AM   #73
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QuoteOriginally posted by and Quote
There is a lot to improve there. Altho speed and sports shooting is I feel the generally weakest point in the current Pentax models, not only the AF speed but also the fps is slower than the canikon offerings, so I just guess this isnt a big priority for pentax its hard to become the sports shooters choice if all of the sports shooters have already settled for canikon. I believe pentax will improve this especially if they release an above-k10d model, but I doubt that will be a speed focused camera with lots of fps and advanced af system.
Well, I am keeping my fingers crossed for more responsive AF and hopefully 5fps. I don't think I need more than that anyway. I am hoping to build a system out of Pentax that will allow me to shoot weddings for a few extra bucks (just maybe one per month) and pursue nature and birding photography which I love. So far my only complaint is shooting in-flight birds...but I have some winners too.
09-16-2007, 04:07 PM   #74
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QuoteOriginally posted by Chako Quote
I may have to disagree with the general direction this thread is going.

I think nobody will argue that Canon and Nikon have a better AF system.

You do not need an 8000 dollar camera to reap the benefits. I have both the K10D and a Canon 20D. The Canon is far better in the AF department.

...

With that said, the new DA* lenses have faster motors in the lens, so that will help in speeding up the mechanical sides of things. This does not help the software side of things however, and this is where I feel Pentax needs to focus more resources on, to remain competitive with sport and wildlife shooters.

Lets face it, you can manual focus anything and be very successful. Auto focus comes into its own if you’re shooting unpredictable fast moving objects however, as you may only have a few seconds to capture your subject. So although I love the K10D, when it is time to do wildlife, I always grab the 20D.
Thanks for sharing your experience with the performance of the Canon 20D and the Pentax K10D. My impression of the general direction of the thread is that most people agree with your opinion. I have noticed that my SDM lens does focus faster than the non-SDM lenses, and as such the SDM system is a step forward. But the AF-C mode is too slow to maintain focus on the kids running towards me at the soccer games. This is clearly an issue with the AF logic rather than an in-lens motor versus in-body motor issue. While I can get some good shots with the Pentax equipment, this limitation has caused me to miss many potential opportunities. Moving vehicles and moving birds are somewhat different both in speed and change of direction (or lack thereof), but I appreciate all those who have shared their experiences.

I like my Pentax equipment for applications where AF speed is not an issue. But I am seriously considering adding a Canon or Nikon long lens and a suitable body to my available photographic tools to cover the sports photography. The challenge now is to figure out whether I want to go with a 70-200mm f2.8 or something longer, and what I need to sell and the available new capital to pay for it.
09-16-2007, 06:58 PM   #75
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As I may have already mentioned, I bought my K10D recently and was extensively reading the current literature before my purchase. I don't think there is any ambiguity on the Canon 40D (certainly even the 30D) being superior for BIF type of photography as compared to the K10D. But, this is not to say that the K10D is forbidden to be used. I think most of the discussion was trying to figure out the optimal way to do it with the K10D. But even with the 40D there is no question that there is a steep learning curve when it comes to BIF.
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