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View Full Version : Using my 10D, I tried out two different 70-200 F2.8 IS


JCalvert
11th of November 2004 (Thu), 14:01
Using my 10D, I tried out two different 70-200 F2.8 IS lenses. Both copies of the lenses had sharp focus on people standing still , but soft focus on those walking toward me ( at normal pace ).

I had IS turned on, 1/200 sec., usually f8 or f11, ISO 200 and set in AI SERVO focus mode. Can someone tell me what is going on here, please?
1) I can't imagine both 70-200s were bad.
2) Was the AI SERVO mode not used correctly.
3) Is the 10D at fault?

What do I look for?

Thanks

PacAce
11th of November 2004 (Thu), 14:12
How many shots did you take in succession? Usually, when the subject is moving towards you and you are using AI Servo, the camera acts in shutter release priority mode for the first picture and then focus priority mode in the subsequent pictures. What that means is that most times, your first picture will be out of focus because the camera will fire even when focus has not been achieved. The subsequent pictures should look better because they'll be in focus.

CyberDyneSystems
11th of November 2004 (Thu), 14:17
And.. even when everything works the way it should... in that situation.. you should be willing to except a percentage of oof shots...

A subject moving closer is easy to fool an AF system.

In this case I do not think you have "bad" lenses.. it is the entire focus systems limitations that are failing you.

JCalvert
11th of November 2004 (Thu), 14:18
I took a few shots, 2 or 3, each time but they are all equally soft. However, thanks for that tip !

samdring
11th of November 2004 (Thu), 14:20
you should be willing to except a percentage of oof shots...
.

Is them 'orses 'oofs :wink:

CyberDyneSystems
11th of November 2004 (Thu), 14:23
Are the 'Orses Out Of Focus? :)

PacAce
11th of November 2004 (Thu), 14:31
I took a few shots, 2 or 3, each time but they are all equally soft. However, thanks for that tip !

I assume you mean 2 or 3 in bursts with a single press of the shutter release button, right? If so, then it's odd that they all came out OOF. :?

hogzilla
11th of November 2004 (Thu), 14:49
Just got the 70-200 4L but without IS and let me tell you i couldn't belive how much i shake when i crank it to 200! I even tried a monopod and i still got camera shake.I think i have to buy a tripod (oh santa) Is this normal or should i cut down the coffee

Persian-Rice
11th of November 2004 (Thu), 14:55
Just got the 70-200 4L but without IS and let me tell you i couldn't belive how much i shake when i crank it to 200! I even tried a monopod and i still got camera shake.I think i have to buy a tripod (oh santa) Is this normal or should i cut down the coffee

Are you an elph? the 70-200 is pretty damn light. Imagine if you were shooting with 2.8, they are heavier and aren't as sharp as the f4, even if it's very minor difference.

Time to start some arm curls :D

PacAce
11th of November 2004 (Thu), 15:02
Are you an elph? the 70-200 is pretty darn light. Imagine if you were shooting with 2.8, they are heavier and aren't as sharp as the f4, even if it's very minor difference.


The 70-200 f/2.8 isn't as sharp as the 70-200 f/4? What makes you say that? ???

Persian-Rice
11th of November 2004 (Thu), 15:06
It just isn't. Don't get me wrong, it's not a big differnce, but there is one.

JCalvert
11th of November 2004 (Thu), 15:36
PaceAce, I was in single shot mode and waited about 1 to 2 secs. between shots.

jc

PacAce
11th of November 2004 (Thu), 16:07
PaceAce, I was in single shot mode and waited about 1 to 2 secs. between shots.

jc

OK, that may explain it then. The camera never really got to get a good lock on the subject since it was moving. With moving subjects, when using AI Servo, it's best to get off 2 or more shots in bursts just to be sure that the camera gets a good lock on the subject. Like I said earlier, the first one shot is bound to be off in focus.

phili1
11th of November 2004 (Thu), 17:22
God I thought it was me at east someone else can't keep it still. I bought a new monopod with three legs on the bottom but with a big lens on it still shakes. I got them there jitters sonney.

dhbailey
12th of November 2004 (Fri), 04:57
I have the 75-300 IS and I can't believe the difference when I am trying to aim the camera and when I press the shutter-release half-way and the IS kicks in. I can't imagine trying to shoot handheld at 300 without IS.

And I can imagine it being difficult with a monopod, although there are things you can do to help when using the monopod -- don't just let the camera rest on it, actually exert downward force on the camera body like you're trying to drive the monopod into the floor. That extra force can help to stabilize the picture. Also, just as with handheld, hold your breath when framing and focusing the shot.

And maybe one or two cups less of espresso before a shoot can help, too! :wink:

Jon
12th of November 2004 (Fri), 09:56
The other factor, and it may not be a major problem, would be how far away the people were, and where on them you were looking. When someone's walking, their arms and legs are moving "faster" than the body as a whole as they swing back and forth. If you were looking at them to evaluate sharpness while the camera was trying to get a focus lock on the torso they may well have been out of the zone of focus and showing some motion blurring as well This would be more pronounced if they're close in than if they're further away.

Cadwell
12th of November 2004 (Fri), 13:02
OK, that may explain it then. The camera never really got to get a good lock on the subject since it was moving. With moving subjects, when using AI Servo, it's best to get off 2 or more shots in bursts just to be sure that the camera gets a good lock on the subject. Like I said earlier, the first one shot is bound to be off in focus.

Good grief! :shock: You must much your way through compact flash cards. Shooting double or more images every time in AI Servo?

The trick is to hold the shutter button half down for about half a second to allow the camera to lock focus and then press the shutter button down fully to take the shot. Nice in focus shots and easy on the storage ;)

JCalvert
12th of November 2004 (Fri), 14:49
Cheers
jc

Jon
12th of November 2004 (Fri), 16:48
Good grief! :shock: You must much your way through compact flash cards. Shooting double or more images every time in AI Servo?


That's why they're called "chips"

:{)#

PacAce
12th of November 2004 (Fri), 16:49
OK, that may explain it then. The camera never really got to get a good lock on the subject since it was moving. With moving subjects, when using AI Servo, it's best to get off 2 or more shots in bursts just to be sure that the camera gets a good lock on the subject. Like I said earlier, the first one shot is bound to be off in focus.

Good grief! :shock: You must much your way through compact flash cards. Shooting double or more images every time in AI Servo?

The trick is to hold the shutter button half down for about half a second to allow the camera to lock focus and then press the shutter button down fully to take the shot. Nice in focus shots and easy on the storage ;)

Canon does not guarantee focus on the first shot in an AI-Servo sequence and I've found that to be the rule rather than the exception with the 10D even when tracking for a half second before taking the shot.
Here, check out this article, section 3.A:

http://photonotes.org/other/ai-servo.html

Cadwell
13th of November 2004 (Sat), 00:38
Canon does not guarantee focus on the first shot in an AI-Servo sequence and I've found that to be the rule rather than the exception with the 10D even when tracking for a half second before taking the shot.
Here, check out this article, section 3.A:

http://photonotes.org/other/ai-servo.html

LOL Don't bother quoting something at me, I know what works for me and what doesn't. I always shoot in AI Servo (motor racing) and I never shoot bursts. My percentage of in focus shots is very high, 90%+ and when it is out of focus or blurred it's usually my fault and I know what I have done to cause it (either snapped at the shutter or shifted the AF point on the target). There's maybe 4% of shots where I can reasonably blame the 10D for getting it wrong.

I did start off shooting bursts with the 10D when didn't know what I was doing but I soon realised that I was wasting my time (and compact flash card space). I get better results firing single shot.

PacAce
13th of November 2004 (Sat), 16:21
Canon does not guarantee focus on the first shot in an AI-Servo sequence and I've found that to be the rule rather than the exception with the 10D even when tracking for a half second before taking the shot.
Here, check out this article, section 3.A:

http://photonotes.org/other/ai-servo.html

LOL Don't bother quoting something at me, I know what works for me and what doesn't. I always shoot in AI Servo (motor racing) and I never shoot bursts. My percentage of in focus shots is very high, 90%+ and when it is out of focus or blurred it's usually my fault and I know what I have done to cause it (either snapped at the shutter or shifted the AF point on the target). There's maybe 4% of shots where I can reasonably blame the 10D for getting it wrong.

I did start off shooting bursts with the 10D when didn't know what I was doing but I soon realised that I was wasting my time (and compact flash card space). I get better results firing single shot.

Whatever floats your boat, Cadwell. I wasn't looking to participate in an argument with you.