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Old Jul 25, 2010, 6:25 PM   #1
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Default Prep for my sports shots -- baby stroller!

In preparation for my trip to football training camp I need to practice using my camera and lens with a moving object. Well, the only thing moving I could find was my daughter's baby stroller. My wife was walking quite briskly around our cul-de-sac in front of my home so I got out my camera and tried to practice with my new 70-300mm IS USM lens attached to my Canon Xsi.

Attached are two photos with a 100% crop and a full version resize (I read the sticky!). Both photos are of a pretty decent brisk walking pace. The one with the stroller alone was a little push of the stroller, so it was moving with some speed. I want your opinions as to what went wrong.

I used aperture priority mode to ensure max aperture. After fumbling with manual for a while I realized that I couldn't adjust the shutter fast enough before the shot was lost so I switched to Av. My goal was to aim for fast shutter speeds 1/500 through 1/2000. I used ISO 1600 to speed things up a bit and AI servo (as I read this is good for moving objects). At 300mm my max fstop is 5.6. I suspect the grainyness is a result of the ISO 1600. Exposure mode was center-weighted averaging.

Keep in mind that I'm used to indoor 50mm f1.8 style photos of food and babies. This moving target and fast shutter speed is making me scratch my head a bit! I appreciate any advice on how to get more clear, crisp and better exposed photos after seeing what I've done here.

Thanks!

John
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Old Jul 26, 2010, 7:19 AM   #2
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Are the non-100% crops cropped at all from the originals? They definitely are on the soft side. Of course if you try to upload photos that are too large the site downsizes them and that downsizing really degrades quality. You also didn't mention but I will point out - make sure you select the center focus point only (as opposed to all focus points being enabled).

On the exposure - the issues here are to be expected - you have dark backgrounds which are influencing the exposure and resulting in overexposed subjects. Switch to partial metering (gives more weight to center of the frame as opposed to the mode you were using). But while you are taking the photos you need to review them on your LCD and adjust exposure compensation so faces are exposed properly. In this case something like -2/3 probably would have worked well. When you're shooting football it will be trickier because players will have helmets so their face will be in shadow.

Now - even if it isn't cropped, the photo of your wife is taken from too far away. You want to be sure the subject fills 2/3 of the vertical frame - that's a good guideline. Beyond that distance you run into much more focus inaccuracies.
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Old Jul 26, 2010, 9:06 AM   #3
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Thanks for your response John. The non-100% pics are not cropped at all. The entire image was opened in paint shop pro x, resized to 600 pixels (width).

Yes, the center focus point was manually selected. Interesting lesson with the partial metering to let the camera add more weight to the dead center of the frame. I see how that could have helped.

That was full 300mm. I'm a bad distance estimator but I'd say 40-50 yards at max? I could have thrown a football to her, let's put it that way.

Thanks for your help, I'll take these tips and try again!
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Old Jul 26, 2010, 9:09 AM   #4
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Quote:
Originally Posted by johnandscooter View Post
... I could have thrown a football to her, let's put it that way...
First Standard. Then Metric. Now Sporty! Well, what's one more method of measurement? I'm on it now.
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Old Jul 26, 2010, 9:10 AM   #5
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One other thing - do you think the ISO 1600 hurt me here? Its my max ISO on this camera but I'm guessing it is going to be necessary for these shutter speeds.
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Old Jul 26, 2010, 9:13 AM   #6
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Quote:
Originally Posted by frank-in-toronto View Post
First Standard. Then Metric. Now Sporty! Well, what's one more method of measurement? I'm on it now.
...
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Old Jul 27, 2010, 7:08 PM   #7
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Ok - how about these?

I set the camera to Av with the largest f-stop I could get, ISO 1600, AI servo and partial metering. The lens was mostly out near 300 mm.

I see that the exposure has worked much better in this set of photos.

But what about the sharpness? What can I do to get more crisp shots? The shutter speeds at ISO 1600 allowed me to really freeze some action but I'm afraid that introduced the grainy look. When I switched to ISO 800 I was down in the 1/250 range which blurred the running. I was dealing with 7:30 pm sun so that could be some of the problem, but it certainly wasn't dark out.

Any thoughts or comments are greatly appreciated. Again, I included 100% crops and then 700 pixel total shot resizes. These are the ISO 1600 shots.
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Old Jul 27, 2010, 7:21 PM   #8
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definitely better. ISO 1600 isn't a problem here. There's a good amount of detail in these. A little bit of unsharp mask and you're good to go.
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Old Jul 27, 2010, 7:26 PM   #9
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I'd be disappointed with the sharpness, too.

Just for the heck of it, try this: http://www.focustestchart.com/
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Old Jul 27, 2010, 7:41 PM   #10
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Thanks guys,

I'm not too familiar with unsharp mask - never really used it before. Here's a quick attempt just to see if I notice any difference after its posted under the originals.

tcav - i'll give that focus thing a shot.
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