filters for sports Alpha 200

[tulsaag]

I just purchased the Alpha 200 and a 70-300 lens. I want to shoot my son's baseball game this weekend (could be day or night) and wonder if I should run out and buy a filter? haven't had time to take a course yet so bear with me I'm brand new.

[inkista]

You don't need a filter for sports, unless you want to physically protect the front element--in that case, get a UV filter.

The big question here, is: can you get a shutter speed fast enough to "freeze the action"? Assuming that you got the Sony 70-300mm f/4.5-5.6 G SSM for your Alpha, if the game is indoors or at night, you may be out of luck. If it's an outside day game, though, you'll probably be ok.

This is because the amount of light you need to get an exposure depends on three things: the iso, the aperture, and the shutter speed. And that lens is limited on its max. aperture (f/4.5@70mm, and f/5.6@300mm). Even with two stops of stabilization, if you were zoomed all the way out at 300mm, you need to be shooting around 1/100s or faster just to eliminate camera shake (to eliminate camera shake, without stabilization, your shutter speed has to be 1/focal_length or faster), and possibly up to 1/500s to freeze the ball in mid-pass. You may simply not have enough light at those smaller apertures to get the shutter speed that high. I would recommend that when you get to the game, take a few test shots, and don't be afraid to max out the ISO if you need to.

Sports can often be the most demanding subject in terms of lenses, because they often require long telephoto lengths, wide maximum apertures, and fast autofocus ability. In combination, that can cost a packet.