Baseball Strike/Ball/TV Question

TV broadcasts frequently include an image representing the strike zone. When it comes to compensating for camera angles, how accurate is this technology?

I’m not sure that I understand your question. But the strike zone, per the rules, is supposed to be the width of home plate, going from the hollow beneath the kneecap to the halfway point between the top of the batter’s pants and the top of the batter’s shoulders.

According to, they use two cameras for the image representing the strike zone, and that presumably helps eliminate “angle bias,” a term I just made up.

Hope that helps.

Technically, the strike zone is three dimensional. It’s the entire area of the plate between the points of the batter you mention. It is a strike if any part of the ball, including the stitching, passes through that 3D area. But this is just an FYI mixed with a nitpick.

I believe the term you’re looking for is parallax.

There’s a lot of technology they can use for this. There was a thread about replacing umpires calling balls and strikes with electronic systems. They do pretty well I think, at least as good as the human umps. They’ll usually show the frame from the perspective of facing the batter, they won’t have such good video from the umps perspective because he’s in the way, but they also show overhead shots that show clearly where a ball just catches the corner of the plate. From what I’ve noticed it’s pretty rare when the cameras indicate the ump has made the wrong call.

Scroll to the bottom of this PDF to see how the 2 cameras are positioned for ESPN’s K zone. The paper is old, but as far as I know, still relevant.

I would think left and right would be easy. The top and the bottom of the strike zone are different for every batter, and I don’t know how the box on TV adjusts for that.

It can’t really, part of the process is based on the umpire’s judgement. The batter moves during the process of hitting, the umpire has to determine where the midpoint of his upper body and where the bottom of his knees are. For the upper body the cameras can be more accurate than an umpire, probably marking the uniform or a better definition for the knees is needed for clarity because of the different stances batters have. But in my recollection the most often controversial calls aren’t about high and low, it’s the ones that may or may not nick the corner of the plate, and multiple cameras can make that very clear.

Maybe I’m misunderstanding your point, or maybe the games you watch have the best umps, but I see the cameras indicate bad calls all the damn time. Several times a game the camera will show balls clearly out of the zone being called strikes, and vice versa, with the added detail that often a pitch in the same location was called a strike earlier but is now being called a ball.

The robo umps can’t take over soon enough as far as I’m concerned.

Most likely I’m not noticing a lot of the bad calls accompanied by camera shots. But I have noticed the cases of the moving strike zone you mentioned, and I guess I should have counted the first pitch errantly called a strike in the totals. There are a lot of pitches in a game, one bad call isn’t that much, but there are games where it gets out of hand.

“Bad calls are a part of the game.” If baseball fans wanted the massive robo-show that football has become, we’d ask for it.

I actually do think a lot of fans (like me) are, indeed, asking for it. Certainly many of my fellow baseball fans do. I’ve never seen a survey, though, that showed what the breakdown is. I’m certainly quite happy with instant replay being implemented. I don’t like seeing teams, even our despised division rival the Cards, get bad called out of a World Series win like they did in 1985. It makes the result feel cheap to me.

Yeah, I know, baseball is going to have to pull itself into the 21st century, speed up, knock off all the slow stuff, put timers on every action, go to multicam instant replay if not robo-umps, and generally find ways to make every minute entrancing to the casual viewr… or die.

I vote for death.

I don’t want robo umps either, except when the bad calls go against my team. So watching the series this year where I don’t care who wins then it’s somewhat more entertaining to consider that there’s a little bit of randomness in the calls. If it was all automated it wouldn’t ruin the game for me either. It’s not up there with the DH rule.

I recall reading this some time ago,

I prefer a game that is as fair and accurate as possible. Your mileage obviously varies.

And, of course, a business magazine’s viewpoint on a sport can only be valid because it’s all about the numbers and the accounting.

Fooling the batter - and the ump - is part of the game. It’s not and never was meant to be a game of maximum precision or perfect accounting. It’s a game. Games are supposed to be fun.

And fair. Blown calls take away the fun for me. As I said above, as much as I hate the Cards, it certainly did not add to my enjoyment of the game to see them not get a World Series ring because of a totally blown call.

The false premise is “the umpire can call balls and strikes wrong.”

If instrumentation, objective reality, or God Almighty Himself disagrees, they can be ejected for arguing balls and strikes just like anyone else. :smiley:

How old is your excerpt from the rule book? Because “fair or foul”, “safe or out” are subject to review now. (And one day, God Willing, we’ll have robo ball and strike calls. :wink: )

And the game is better for it.

If the error rate is 14% then I have no argument. That’s professional wrestling quality officiating. I’ll stick to not paying close attention though.