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08-13-2010, 12:17 PM   #16
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Hi Tom,

If AF speed is a consideration in your decision, I'll inject something that might be an important consideration -- Quick Shift focusing.

I'm not a sports shooter -- I shoot birds, and use AF since I can't trust my vision for focusing, and I need to use tricks to overcome limitations in the AF system. Shooting sports will have some similar requirements. In lower light situations, when the AF system starts to struggle, full lock focusing hunts that overshoot the focus distance in both directions can get really frustrating, and many shooters will just give up.

The problem can be overcome significantly by manually focusing to close to the focus point, then letting AF take over. This gives the AF system some contrast to work with to begin the process. If the lens is way out of focus, everything is a blur, and there is no contrast for the system to work with. The problem with most older lenses is that it's a pain to switch from AF to MF and back to AF. Quick Shift eliminates this problem and makes a slower max aperture lens a lot more usable at light levels where the AF system is starting to struggle.

If you have any AF lenses, this can be easy to confirm. Pick an indoor location where the AF struggles, but there's enough light to easily see your subject. Pick a relatively low contrast subject, and at a medium distance, start at infinity, and actuate the AF. If the light is low enough, you'll see the focus overshoot the proper focusing distance and go all the way to the other extreme. It will continue to do this both ways, but you might get lucky and have the focus actually lock, but only in a small percentage of tries.

Switch to MF, and give the focusing system a starting point close to proper focus, then switch back to AF and actuate AF. You should see a dramatic improvement in AF lock percentage. If you don't have a QS lens, then imagine how much easier this would be if you didn't have to manually switch between MF and AF. . .

Another trick is to use AF C and just wait for the first reversal in AF direction. This takes your camera out of focus lock priority and allows you to shoot without the prerequisite of waiting for a confirmed focus lock. Timing the shots takes some practice and a lot of concentration, and it will be a test of your reaction time, but I use this technique quite a bit, and at 60 yo, my reaction times are not what they used to be. . .

If you can get away with 200mm at the long end, I think the DA 50-200 would be a good choice. If you find the manual prefocus thing a benefit, then you'll want to look for a standard DA 50-200, not the DA50-200L as the latter doesn't have QS focusing.

Good luck in your choice.

Scott

08-13-2010, 07:22 PM   #17
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I appreciate all the help, everybody! I found a very good deal for the DA 50-200, so I think I am going to start with that, which would also leave me with enough money to get a decent monopod. Plus, the quick shift seems like it could really aid in low light focusing. I also have that Vivitar 70-210 f/4 I can try, and if I find I'm decent enough with manual focus for those sports games I can probably scrounge up enough cash to invest in an A 200mm f/2.8 or something along those lines.

Anyway, thank you all for the help!

-Kevin
08-13-2010, 08:53 PM   #18
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I shoot our HS soccer team which is single A in size. The new season is just starting & I'll be using the Tamron 70-300 again this year. Single A size teams usually don't have the best lit stadiums, but I get by very well with the K7. The games in our area start at 7pm so there is still a little daylight left for the first half which helps allot. I will switch to the
Sigma 50 f/1.4 for some really late game victory celibrations or sideline excitement & then crop ( get as close as you can of corse). I do usually take video second half with a shotgun mic (Azden SGM-X) as I do create a DVD for all the players and to be shown at the year end banquet. It has worked for me, not perfect for sure.
08-15-2010, 07:56 AM   #19
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QuoteOriginally posted by Tomzee93 Quote
I appreciate all the help, everybody! I found a very good deal for the DA 50-200, so I think I am going to start with that, which would also leave me with enough money to get a decent monopod. Plus, the quick shift seems like it could really aid in low light focusing. I also have that Vivitar 70-210 f/4 I can try, and if I find I'm decent enough with manual focus for those sports games I can probably scrounge up enough cash to invest in an A 200mm f/2.8 or something along those lines.

Anyway, thank you all for the help!

-Kevin
I use a lot of manual focus lenses, but, I admit, with subjects that are not constantly moving. I think if you have the chance to shoot an outside game with the Vivitar you will learn a lot about exposure and pre focus. You will also have control over placement of the main subject. In addition, if you find your autofocus lens struggles with lower light focusing you will enjoy having control via manual focus. Prior to the 80's all of this stuff was shot manual.

Having said that, you could purchase a used fast autofocus lens, use it for a season and then resell it for close to what you paid for it. The used lenses tend to hold their value. If you spend some time you may pick up a bargain and be able to resell it for slightly more than you paid.

I also think an inexpensive 135 2.8 manual focus prime would work well if you have access to the sidelines.

If you are shooting inside a gym you may want to search for strobist gym. If not familiar with off camera flash you will learn a lot and the manual flash unites are inexpensive and you can use slower lenses.

This shot was taken with a old and wonderful manual focus SMC Takumar 200 f/4 two weeks ago. The shot is not cropped.




Last edited by stover98074; 08-15-2010 at 08:07 AM.
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