Soccer - The quest for sharper images

[LL III]

Any suggestions on capturing a sharper image with autofocus. I struggle ensuring that the camera focuses on the subject. So many players, at so many distances and the fast pace of the game. I've included two photos from a recent game; one in relative focus and the other not so... I'm dying for those razor sharp images.

LOL I think I'm quickly becoming obsessive.

1st Photo

Camera Model Canon EOS DIGITAL REBEL XT
Shooting Mode Shutter-Priority AE
Tv( Shutter Speed ) 1/800
Av( Aperture Value ) 2.8
ISO Speed 100
Lens Tamron 70-200 f2.8
Flash Off
White Balance Mode Cloudy
AF Mode AI Servo AF

2nd Photo

Camera Model Canon EOS DIGITAL REBEL XT
Shooting Mode Shutter-Priority AE
Tv( Shutter Speed ) 1/640
Av( Aperture Value ) 3.2
ISO Speed 100
Lens Tamron 70-200 f2.8
Flash Off
White Balance Mode Cloudy
AF Mode AI Servo AF

[karen_s]

I think they look pretty good. You've captured a couple of really good moments and that is half the battle of getting great sports shots.

One does look sharper than the other. In the first the action seems to be moving toward you and in the second, the action seems to be more steady in one place or moving parallel in front of you. You lens's ability to focus quickly could be an issue.

That's just a guess though. To help narrow it down, could you post your exif data (ISO, shutter speed, aperture, focal length, focus mode ... ) and what camera body and lens you are using? That would be a great help in determining if there is something more you can do to improve sharpness. There's a great bit of difference especially in lenses for both sharpness and focus speed. I had a cheaper Sigma ($180) zoom and it was fairly sharp at 200mm but outside of that, not so hot. It focused slow too. I sold it after about 3 months and bought the Canon 70-200mm 2.8 IS (ouch the price hurt!) and my percentage of sharper images rose dramatically.

If it does turn out your lens is the limiting factor, both of these shots still look sharp enough to take into Photoshop and sharpen. Google can help you with that :-)

I'll check back once you get the exif data posted and see if I can offer you any tips.

[LL III]

Thanks Karen_S

I posted the EXIF data for each of the photos. Aby additional comments would be apprectiated. I was shooting the Tamron 70-200 f2.8 lens. The Canon equivelant was a bit too pricey for my budget. Also, shooting with an older, entry level XT body. Working my way to a 50D (Money).

[karen_s]

Were you reading my mind? I didn't see the exif data until after I posted. Please assure me that I was not so blind as to miss it :-)

Anyway, your settings look pretty good overall but one thing does stand out and that is the aperture. The depth of field (DOF) at 2.8 is rather short. (Don't get me wrong, I love 2.8 and start there most of the time.) An athlete running straight at you will move in and out of that DOF range rather quickly which means they may be moving from a sharp space into a blurry space faster than your lens can accommodate. If you were really close to your subject or zoomed in all the way, that DOF space can get even shorter.

I might suggest experimenting with slightly narrower apertures. You want to keep the shutter speeds up so you may have to go bit higher with the ISO but the narrower aperture can give a longer space and a bit of wiggle room for focus.

There may be some other things you can do but this is the one that stands out to me.

[karen_s]

Oh I upgraded from and XTi to the 50d awhile back and it was a great leap forwards. The XTi was a nice entry level camera but it really paled in comparison to the 50d. I know there are better cameras but for my skill level, the 50d is quite good.

And your lens looks to be a pretty good one. Even with the Canon 2.8, I still get some blurry shots when the action is coming right at me. I just keep practicing and experimenting.

As far as post process, do you have Photoshop? The Unsharp Mask method can really do wonders for photos that are close.

[LL III]

Great input! And I see what you're saying about the DOF at 2.8. Great if the action is a static, difficult as the subject moves in and out focus. I like to capture the action coming at me which compounds the problem.

I do have photoshop, but am not familiar with "unsharp mask." Can you elaborate?

[karen_s]

I'll start by saying I'm not much of an expert on sharpening and have just started playing with it. I have been Googling the topic to learn how other photographers go about it. There are many ways to get to the same place. It does seem best to start with as good an image as possible as sharpening will only enhance what you already have. I wish it could fix disasters but sadly, it can't :-(

As for Photoshop (i'm looking at CS4), in the drop down menus, go to Filter > Sharpen > Unsharp Mask .... You should get a pop up window with three sliders ... Amount, Radius, and Threshold. They all do something a little different. Amount is self explanatory, bigger number, more effect. Radius I think has to do with the spread of the pixel being sharpened or something like that. Most of what I have found said the default of 1.0 is usually quite adequate and to just leave it. The third is Threshold, which I am still learning about. It appears to smooth areas but not sure.

I'd suggest just opening an image (a copy would be best ;-) and moving the sliders around to see how the image is affected. That big box in the pop up window gives you a chance to pixel peep and really see the effect as you experiment.

Hope that's enough to get you started.

[wamplers]

I would increase ISO. I don't like shooting at 1/640 and 1/800 unless I have to, and there's no reason IQ wise to stay at ISO 100. Go to 200 or 400 ISO and crank those shutter speeds up there. If you still get soft images, then you might want to look at maybe f/4 and see if that helps.

[inkista]

Originally Posted by wamplers

I would increase ISO. I don't like shooting at 1/640 and 1/800 unless I have to, and there's no reason IQ wise to stay at ISO 100. Go to 200 or 400 ISO and crank those shutter speeds up there. If you still get soft images, then you might want to look at maybe f/4 and see if that helps.

+1.

Plus, maybe next time going for a lens that's got USM (Canon) or HSM (Sigma) in it--having that ultrasonic motor to throw the glass around a little more quickly can sometimes help out with autofocus speed.

Three other things to keep in mind:

Always wait to see that your photo's in focus before pressing the shutter. It's a pain, I know, but smashing the shutter "in hope" works less well than knowing you've got focus lock before taking the pic. Also, if you're shooting in continuous mode, short controlled bursts are going to work better than long bursts of "spray'n'pray." Pick your moments. I found with my XT that while in burst mode, the camera often didn't have time to adjust AF between shots, and the focus would lock at where it had been set on the first shot in the sequence.

Secondly, you may want to consider learning how to use back-button autofocus.

Thirdly, the XT's AF system is relatively primitive--you only have 7 AF points and only one cross-type sensor in the center, rather than the 9 points that's the default for the current dRebels, or the all-cross-type 9-pt. array of the 40D/50D. I used an XT before I got my 50D, and the AF system's speed and accuracy were always a minor irritation to me while I was shooting birds in flight. Doesn't mean you can't get the shot, but you are going to have to work a bit harder for it. I know it sounds crazy, but I sometimes found I was getting better shots of moving targets in One Shot mode using only the center point than I was in AI Servo with the full AF matrix.

[wamplers]

Originally Posted by inkista

I sometimes found I was getting better shots of moving targets in One Shot mode using only the center point than I was in AI Servo with the full AF matrix.

What about AI Servo with only the center point? This is how I shoot with my 50D 99% of the time for sports. I also 2nd the idea to focus using the back button...that's all I ever use anymore.