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Lars Johnsson wrote:
A few quotes from your 3 links. Where you tell us that the 1D4 is the biggest failure ever.
"Auto focus tracking (AI servo) does a phenomenal job on subjects that are moving fast. I tracked bald eagles and hawks flying at and around me. I tracked huge flocks of snow geese flying straight toward me. I rapidly turned and caught a mallard landing on a pond. In all of these cases, the auto focus quickly locked on its target and tracked it. In almost all of these sequences, every shot was in perfect focus"
"As always, what matters is reality - how the design works in real life. And in real life use, the statement I am continually telling myself while reviewing my 1D Mark IV shots (especially those taken in AI Servo mode) is ... I'm impressed.
Canon's DSLRs typically perform very well in One Shot AF mode. Like the 1D Mark III, the Canon EOS 1D Mark IV One-Shot-focuses very fast and very accurately. I don't perceive any differences in AF lock timing between the two"
"We'll get right to the point. The EOS-1D Mark IV's AF system shows signs of brilliance. For example, while testing the camera's ability to track an athlete running straight towards the camera, the EOS-1D Mark IV locked onto the subject and would not let go, producing sequence after sequence of mostly in-focus pictures. In several rounds, 25 or more frames in a row were either perfectly focused or just slightly out.
On the same track and under effectively identical test conditions to those that tripped up the EOS-1D Mark III's AI Servo AF every time, the EOS-1D Mark IV nailed it.
...Show more →
Yes, it is amazing how selective editing will make even a flawed camera look good, Lars. What are you trying to prove?
Here, let me help you find the parts you lost:
"Update 2/17/2010: Since writing the original review, I've had opportunity to shoot a couple of different AI Servo scenarios with the Canon EOS 1D Mark IV. Downhill skiing was the most AF-stressing of these and while the center-only AF point continued to work well (though not as well as with soccer - and poor with a no-contrast solid-black-clothed subject), specific peripheral AF points delivered only fair performance - missing some shots I thought it should not have missed and missing some by more of a distance than I previously experienced.
Update 4/07/2010: I shot a soccer game last night. The weather was hot, the sun was low in the sky and the uniforms were mostly solid white. Looking at the results, I wondered if I was using the same camera that I shot soccer with a couple of months ago. There were a higher percentage of OOF shots (that should not have been OOF) than I am used to seeing with this camera. The positive side was that I got some of the best sports shots I've ever taken.
Update 6/06/2010: Many thousands of sports action shots later, I can say that the 1D IV indeed lets me down on occassion. I haven't been able to determine any consistent factors for the cause of OOF AI Servo shots, but heat and the color white were often involved (FWIW). And still, very frequently, the 1D IV delivers a very impressive focus hit rate - as I saw in my original testing. So I believe that Canon still has room for improvement in this regard. "
And:
"While the 1D Mark IV’s autofocus system is almost perfect with birds in flight, it was ho-hum with birds swimming on a pond. I tracked cormorants and several types of ducks on the pond and discovered no matter how slow they swam, the auto focus couldn’t keep up.
The problem occurs mainly with birds that swam just slightly away from me. I would pan with the birds. In a typical burst sequence, the camera would get the first two shots perfectly in focus and then would get bored and stop tracking the bird.
By shots four or five, the point where the camera focused was significantly behind the bird. Eventually, it would correctly track the bird again for a few frames, only to fall behind again. To put it another way, this is an issue in sequences where you need some, although very little, change in focus from frame to frame."
And:
"When photographing a cormorant hunting from a log, I selected a solitary auto focus point that just fit within the bird’s head. Even still, the camera seemed to be distracted by the similarly-colored grass and brush behind it. AI servo caused the focus to ping-pong between the bird and the brush. In single-shot AF, about half the time the camera would focus on the brush."
And there is a very good reason why RG chose the words "shows signs of brilliance" instead of "brilliant, to wit:
"At speedskating, the camera managed a healthy number of in-focus frames of skaters rounding the corner, but coming down the straightaway towards the finish, and beyond the finish (where the winners will typically pump their fists), the results were mixed to poor. Too often the EOS-1D Mark IV would frontfocus significantly or, alternately, appear to stop autofocusing altogether.
Through over 150 pairs of fast 500m and 1000m skaters, as well as skaters in the slower 5000m event, the camera at times rose to the occasion, netting 10+ consecutive in-focus frames in a sequence with some competitors. At other times it would misfocus for almost as many frames.
Particularly puzzling was the camera's behaviour once the race was over: as skater after skater stood upright just past the finish, the camera would lose focus and sometimes not recover. If we had been photographing real races and not time trials it would be the point where the winners celebrate. This is not a good moment for the AF system to act up.
Going Up: Canon EOS-1D Mark IV (firmware v1.0.6) + EF 70-200mm f/2.8L IS at 80mm, ISO 200, 1/500, f/6.3, Dyna-Lite Arena strobes. Click photo to enlarge (Photo by Rob Galbraith/Little Guy Media)
At basketball, the EOS-1D Mark IV didn't rise above the level of fair-to-middling. It made in-focus frames in both available light and strobed shooting - including some frames we're happy with, such as the one at right - but it missed about as many frames as it got.
When looking at the available light photos, it was apparent why: like speedskating, the EOS-1D Mark IV was too often shifting the focus way out in front of the subject. At other times, the focus was inexplicably drifting behind. After six games, what the pictures show is a camera that's neither very good nor terrible at autofocusing the sport of basketball.
The EOS-1D Mark IV's autofocus performance through 4.5 games of soccer was bizarre.
We've shot two games - one as night began to fall and the other lit only by high school stadium lighting - in which the AF system worked quite well, locking in on key moments, capturing many in-focus frames in extended sequences and generally doing about as good a job as we could hope for given the conditions.
We've also shot one late afternoon game, and half of another with a mix of low sun and stadium lights, in which autofocus performance was just so-so. There were some crisp moments and decent sequences but also an unacceptable number of frontfocused frames as well as a few backfocused ones, much like basketball (though the overall take was somewhat better than basketball).
Rounding out the soccer experience was one game in which the AF system verged on total collapse, much like the EOS-1D Mark III in its early days. The game took place on a beautiful sunny morning and the play was frontlit, meaning that conditions were not what we'd consider strenuous for autofocus. Curiously, the EOS-1D Mark IV's autofocus improved when the sun went behind a cloud at several points. By comparison, its autofocus fell off a cliff when the sun was out and the players in red jerseys were being photographed."
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I don't think anyone is happier now that I have posted the parts I was referring to in the first place, as you surely could have figured out on your own, if you had wanted to. Yes, the camera is sometimes brilliant, but if it sometimes fails dramatically, who the hell would be happy?
Edited on Mar 03, 2011 at 08:19 AM · View previous versions
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) is that my 24-70 2.8L is really more a 24-70 4L or thereabouts.