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Old Sep 20, 2007, 1:15 PM   #21
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Yeah, I'm constantly amazed that the more I practice the better my camera seems to get.
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Old Sep 20, 2007, 4:25 PM   #22
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DarkDTSHD wrote:
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When in fact there is some skill to getting AI Servo to track properly sometimes. Understanding how it actually does it's job would also help. As you said.
Exactly!

1. The most fundamental thing that most user fail to understand is that in AI-servo the camera does not have to be in focus at all for the shutter to fire - In fact you can put a lens cap on (or cover the lens entirely with your hand) and release the shutter at will with nothing at all in focus. This is called shutter-priority as opposed to focus-priority as in one-shot AF where the shutter will only release if confirmed by a focus point (i.e. this mode will fail the lens cap test)

2. AI-servo is also predictive which means it'll guess on where the subject will be when the shutter is released and not neccessarily on what the AF sensor 'see' before the mirror is up, or when the shutter curtain is opened. For a fast moving subject this is great; However if an object is at a stand-still but the photographer shake his camera during the shot instead, AI-servo does not know the difference as its AF 'saw' the movement and will predict the still object trajectory which had not bulge a bit hence the mis-focus.

3. An experienced photographer will allow the camera to track the subject first before releasing the shutter if not he'll run into #1 above where the shutter will release anyway regardless of the AF. AI-servo is most efective in a burst where subsequent shots are better able to track a subject than the 1st shot, provided of-course that the AF points can remain on the subject throughout the burst - Otherwise all bets are off which is why AI-servo do not work well on small birds (as the AF points alternate between the backgrounds and the subject)
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Old Sep 20, 2007, 11:46 PM   #23
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NHL wrote:
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DarkDTSHD wrote:
Quote:
When in fact there is some skill to getting AI Servo to track properly sometimes. Understanding how it actually does it's job would also help. As you said.
Exactly!

1. The most fundamental thing that most user fail to understand is that in AI-servo the camera does not have to be in focus at all for the shutter to fire - In fact you can put a lens cap on (or cover the lens entirely with your hand) and release the shutter at will with nothing at all in focus. This is called shutter-priority as opposed to focus-priority as in one-shot AF where the shutter will only release if confirmed by a focus point (i.e. this mode will fail the lens cap test)

2. AI-servo is also predictive which means it'll guess on where the subject will be when the shutter is released and not neccessarily on what the AF sensor 'see' before the mirror is up, or when the shutter curtain is opened. For a fast moving subject this is great; However if an object is at a stand-still but the photographer shake his camera during the shot instead, AI-servo does not know the difference as its AF 'saw' the movement and will predict the still object trajectory which had not bulge a bit hence the mis-focus.

3. An experienced photographer will allow the camera to track the subject first before releasing the shutter if not he'll run into #1 above where the shutter will release anyway regardless of the AF. AI-servo is most efective in a burst where subsequent shots are better able to track a subject than the 1st shot, provided of-course that the AF points can remain on the subject throughout the burst - Otherwise all bets are off which is why AI-servo do not work well on small birds (as the AF points alternate between the backgrounds and the subject)
Great advice NHL! I'll definitely remember those tips.

Have a good weekend.
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Old Sep 22, 2007, 2:00 PM   #24
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i've had my 40D for about 2 weeks now, and i like it a lot. there are some subtle differences in controls, feel, etc., but the main difference i in the images is that the 40D produces a much smoother, richer photo, with better color depth and smoother tonal gradation. probably because the Digic III chip "sees" 4x as many colors per channel as the 30D. in any case, the results i've gotten so far - admittedly not much, because the weather's been crap most of the time since i got it - do appear cleaner and sharper, and with better color, than the 30D produces.

here are some sample shots from the 40D... hard to see much difference in these sizes, but in the full-size shots, it's easier to tell...








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Old Sep 22, 2007, 10:26 PM   #25
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I just got my 40-D a week ago. WoW!!! Its a very nice upgrade over the 20-D.

The most enjoyable thing about it is the much more silent shutter.

Colors are smooth and even and it just feels right. I have also noticed that my micro shot keeper rate has risen. The 150mm Sigma macro does not hunt as much as with the 20-D.

I love it. 5 stars to you Canon!!!!!
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Old Sep 28, 2007, 3:43 PM   #26
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Hello guys,

I know, for the most part, 90% of 40D owners are happy. Virtually no complaints about the AF (one shot or AI Servo). Yet there was a test done by one user, by the name of "drew" (http://www.prophotohome.com/forum/pr...w.html?garpg=2), where the initial photos of the series were not in focus. But later became in-focus....etc.

In other forums, 40D users claiimed it was "user error". Was it? I'm not so sure now as Rob Galbraith's site just posted an article about the 1DM3's AF problems. One of which was what drew found in his test. Here is the article about the 1DM3's 4 AF issues. Still occuring according to the article...

http://www.robgalbraith.com/bins/mul...id=7-8740-9068

Have all your AF experiences been positive using all the modes? Or have you run into any of the 4 mentioned in the above article talking about 1DM3?

Thanks.
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Old Sep 28, 2007, 10:11 PM   #27
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Just to confuse matters:

my 1dmkIII focuses just fine - even when using 300mm 2.8 lenses in bright sunlight.

Go figure
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Old Sep 28, 2007, 10:22 PM   #28
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i got my 40d a bout a week ago, i upgraded from an xt that i had been shooting with for 2 years.... i like the functions of the cam, altho the settings are taking a bit to get used too....



heres a shot of a deer from last weekend
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Old Sep 28, 2007, 11:14 PM   #29
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JohnG wrote:
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Just to confuse matters:

my 1dmkIII focuses just fine - even when using 300mm 2.8 lenses in bright sunlight.

Go figure
You must have got the Special Edition 1DM3!
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Old Jan 3, 2008, 3:30 PM   #30
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Chris:

I do a lot of hockey myself (my son plays PeeWee travel hockey in Michigan).I've always experimented with different settings, etc. I just got my 40D to replace my 30D and I can tell you that I've had a lot of frustrations with the AI focusing. It tends to hunt a lot and not lock on to any subject. My 30D, and 20D for that matter, were much better. I have sent it in to Canon for evaluation. Hopefully they can get it solved.

Do you mind sharing the settings you're using with your 40D in the rinks. I realize each rink is different in terms of lighting, but something to get started. I'm using a Sigma 120-300 f/2.8 lens.

Thanks!

Doug
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