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Old Jan 24, 2007, 11:31 PM   #11
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BrettTurner wrote:
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But you don't literally have to keep the 70-300 at 70mm; you just need to stay aware of the aperture breakpoints. On my K100D with the Tamron 70-300 attached, max aperture is F4 from 70-120mm, F4.5 from there to 220mm, and F5.6 above that. So anything at or below 120mm should be the same as 70mm. Even up to 220mm, you're still at F4.5, which is only a minor loss over F4. The big problem comes when you zoom past 220mm, because F4.5 to F5.6 is a big jump, which could cause a 50%+ increase in shutter speed if everything else is constant.
I agree with Brett, at least in theory. You do not have to stick to 70mm. I don't have the Tamron 70-300 lens so I wasn't aware of its break points, but if you can get the f/4 aperture up to 120mm, then go for it. It's certainly worth a try and I am glad to be corrected on this point.

I do however see a potential PRACTICAL difficulty. I'm not disagreeing here with Brett, just expressing my anxiety about how you actually make this work. When I'm shooting basketball, I'm too busy trying not to miss the best shot of the afternoon to worry about exactly what my focal length is. Focal length is not one of the pieces of info displayed in the viewfinder, is it? Unless you were to look at the lens barrel constantly, I am not sure how you would be able to tell what focal length you were using. The size of the people in the viewfinder doesn't tell you: they get bigger as they run towards you even if you don't change the focal length. I'm not saying it's not possible. I've never tried. But I doubt that I personally could make it work.

That is one of the major attractions of a zoom with a fixed maximum aperture - you simply don't have to worry about this sort of thing. If you can stay close to your subjects and use just the low end of the telephoto zoom, that's great. If you accidentally push it over 119mm, and you lose a half of a stop or whatever it amounts to, well, it WILL make an instant difference to the picture - the picture will get noticeably darker. You might be able to fix it post-processing, well enough.

Will
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Old Jan 24, 2007, 11:33 PM   #12
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I'll mention an overlooked lens - any of the manual 135mm f/2.5 or 2.8 lenses. One just sold on ebay for $50. I've purchased them for as little as $5. At f/2.5 or2.8, you'll get a faster shutter speed and the reach is decent, especially for high school sports where you can get closer to the action.

Also, I've read (but not tested) that 1/640s is the minimum speed to freeze sports action. Perhaps JohnG will chime in. He posts here often and is very good with his sports shots.

Russ
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Old Jan 24, 2007, 11:51 PM   #13
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rfortson wrote:
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I'll mention an overlooked lens - any of the manual 135mm f/2.5 or 2.8 lenses. One just sold on ebay for $50. I've purchased them for as little as $5. At f/2.5 or2.8, you'll get a faster shutter speed and the reach is decent, especially for high school sports where you can get closer to the action.
I got my Pentax M 50mm F1.4 from KEH for $115 used by in excellent condition. They had one in "bargain" condition (probably just as good, though) for considerably less. In terms of the glass alone, it's probably the best lens I've got. The problem is, it's hard to use. It's manual focus and manual aperture, too. I use manual focus a lot when I'm shooting a subject that sits still for me and lets me really think carefully - say, a perching bird. But on the basketball court, I find manual focus really difficult, not least because the viewfinder in the K100D just isn't as clear as one could wish. I've ordered the Pentax 1.2x magnifier - not much, but something perhaps. But I still don't think it's going to make it possible for me to start using manual focus with much success at sports events.

On the other hand, who knows. Maybe it just takes practice. Certainly true that used lenses are the least expensive way to improve your equipment collection.


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Also, I've read (but not tested) that 1/640s is the minimum speed to freeze sports action. Perhaps JohnG will chime in. He posts here often and is very good with his sports shots.
There isn't a rule about this, can't be, for lots of reasons. "Sports action" is not a constant like the speed of light. Capturing a golfer in mid-swing and freezing the club might take a really fast shutter, but catching the golfer at the end of the swing with the club high in the air might be possible with a much slower shutter. The girls that I photograph don't move as quickly as NBA all stars. A free throw is easier to photograph than a steal or a fast break. And how fast the shutter needs to be depends in good part on the perspective from which you are viewing the action. If the player is running directly at me, the motion is less evident - and thus easier to freeze - than if the player is running right past me from side to side. And even when THAT happens, I may be able to pan the camera and have done so with some success. You can see the EXIF info for the shots in the gallery that I linked to in my first response here. I don't think any of those shots was taken with a shutter faster than 1/500s, and quite a few were taken with considerably slower shutters. I'm not expecting Sports Illustrated to hire me to cover the NBA, but the results are good enough, considering all the compromises I have to make to be out there shooting at all.

Bottom line: you have to experiment, review, think, experiment some more, etc. What I'm finding is that it's lots of fun, but a much bigger challenge than I realized when I got started.

Will
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Old Jan 25, 2007, 1:55 AM   #14
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" At 5.6 you can't get the minimum 1/500th of a sec. shutter speed to freeze the action indoors."

Then again with the K's IS.... you could easily drop that down to 125 and stop all but fastest movement.... but still probably to fast for that lens unless very well lit.
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Old Jan 25, 2007, 8:05 AM   #15
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Will & Brett,

Thank you very much for the information! Those few posts have given me some great tips. If I could get a little (physically) closer to the action, I could back off on the zoom and use the wider aperture. My problem is that my son gets a little embarrassed when I'm kneeling on the sidelines like a pro photographer. He would much rather I sit up in the bleachers with all the other parents.:roll: I guess my wife would too.

I'm going to print out this thread and try many of those tips and settings at the next match. Thanks again for the information. I love this place!

-Matt
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Old Jan 25, 2007, 5:07 PM   #16
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Polytrope and Gadgetnut:

You don't see the focal length in the viewfinder, but you do see the aperture, constantly updated as you zoom back and forth. Shooting birds through my kitchen window this morning, with the camera in P mode, I could easily see when I crossed a breakpoint; the aperture would suddenly change from F4 to F4.5 to F5.6. I wasn't shooting action so I didn't need a fast shutter, but I still needed every ounce of light I could get into the camera---early AM, overcast day, with the window eating up a stop or so of light---so I tried not to shoot at F5.6 unless there was a good reason.

Shooting action, one would normally use Tv mode to freeze the shutter speed at a level which minimizes motion blur. The camera then sets the aperture according to the available light. In low light conditions, the camera will almost always select the widest aperture the lens allows. So again, you simply watch the aperture; the fstop will jump suddenly at the break point. (Probably best to fix the ISO, rather than using auto ISO, to eliminate the possibility of an aperture change caused by an ISO shift).

In manual mode, you should be able to set shutter and fstop for the ideal conditions, for example 1/200 at F4.5. If you zoom past 220mm, so that F4.5 isn't available anymore, the camera will set the aperture to F5.6, the best permitted by the lens, and IIRC the F5.6 flashes to warn you that your exact manual settings can't be used anymore. The jump in aperture again shows you the break point.

Summary: fix the shutter speed and ISO, watch the aperture, and take your shots at the lowest fstop you can. As a side effect, if there's not enough light you get a dim picture, not a blurred one, which gives you more options in post-processing. If your pictures are too dim and ISO has been maximized, your options are (1) use a slower shutter and accept the motion blur, (2) use a flash if close enough, (3) use less zoom to get a wider aperture if your lens allows that, or (4) buy a faster lens.

--Brett


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Old Jan 25, 2007, 8:48 PM   #17
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BrettTurner wrote:
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You don't see the focal length in the viewfinder, but you do see the aperture,
I entirely withdraw my reservations to Brett's suggestion. Use the lens you've got and keep your eye on that aperture. I do it all the time myself. Just forgot that it was the aperture we were talking about, not really the focal length. To quote the immortal Homer Simpson: D'oh!

You may still end up buying a new, faster lens - I did. But it makes good sense to give what you've got a try first and see how far you can push it.

Will
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Old Jan 25, 2007, 9:29 PM   #18
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Polytrope wrote:
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The problem is, it's hard to use. It's manual focus and manual aperture, too. I use manual focus a lot when I'm shooting a subject that sits still for me and lets me really think carefully - say, a perching bird. But on the basketball court, I find manual focus really difficult, not least because the viewfinder in the K100D just isn't as clear as one could wish. I've ordered the Pentax 1.2x magnifier - not much, but something perhaps. But I still don't think it's going to make it possible for me to start using manual focus with much success at sports events.


Just focus on a spot/area of the court and take shots when the players get there. Around the basket is the obvious spot. I used this technique with my manual focus 135 at an NBA game and it works fine. Sports were photographed for many years before autofocus came into being. Oh, and that 1.2x magnifying eyepiece really makes a difference with focusing. I got one a couple of weeks ago.

Here's one example of a 135 f/2.8 shot taken from the other end of the court. I think it came out okay. Of course the lighting is MUCH better in an NBA gym, but I'm MUCH farther away,



BTW, I didn't say the 1/640s was my rule, but it was suggested in one of my photography books as the minimum speed to make sure you freeze the action. That's assuming you want to freeze the action, of course.

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