I bought the I-phone serve radar app

[Fedace]

What if you hit the iphone with your serve and it goes into 1000 pieces. would it be covered under warrantee ??

[LeeD]

No BS here....
I think MofP can serve right above 130 IF he flattened out his top/slice.
As is, closer to 115-120 max.

[stoneage]

Originally Posted by Fedace

What if you hit the iphone with your serve and it goes into 1000 pieces. would it be covered under warrantee ??

You are measuring from the side, so the risk is minor
/Sten
______________________________________
racquetTune, swingTool and netHeight, tennis apps for the iPhone.

[LeeD]

Still, nobody tried?
I think it's impossible to get accurate readings from different people at different sites using exactly the same EQ. Just like theory is different from reality. Lab conditions are not directly applicable to the real world.
I DO hope it works.

[Bud]

Originally Posted by TheMagicianOfPrecision

Now where on the court shall I place it in order for it to "count" and be the most accurate !?

The app has gotten lots of great rewiews and recommendations so I guess it is working really well.

I will post the results on Thursday:

Just for fun, plz post how fast you think i will hit!

So??

What was the result?

[Timbo's hopeless slice]

there was a radar on the show court of the last tournament I played.

My best was a lowly 119 but I average about 112, I can live with that...

(of course, on TT, I actually serve at 135!)

[LeeD]

119 on one radar at one location MIGHT well be 135 from another radar at another location.
You know DavisCup always produces the fastest serves.
Now try serving in 52 degree weather with DunlopHDHardCourtChamp balls. Your 119 goes down to 109.

[5263]

Originally Posted by Timbo's hopeless slice

there was a radar on the show court of the last tournament I played.

My best was a lowly 119 but I average about 112, I can live with that...

(of course, on TT, I actually serve at 135!)

112 mph is a pretty nice avg!
Good show

[TheMagicianOfPrecision]

I did try it 10 days ago, totally forgot to tell about it.

It didnt work at all, good thing the price only was 0,99 USD.

I had a friend of mine standing to the side, between the baseline and the service-line and i hit 10 serves. It showed everything from 75 mph-95 mph, no matter how hard i hit it wouldnt go over 95 mph So...to the creator of the app, take it and stick it where the sun dont shine.

[papa]

Not exactly a "ringing endorsement" one way or the other.

Even with pretty good radar guns the speed can and does vary depending on your location in relationship to the court, brightness, weather, new ball vs old ones, etc.

For the serve, I've found one of the best spot is looking through the net at the server - still will vary but a lot more consistent.

[TheMagicianOfPrecision]

I agree.

But this was just way off, imagine you hit some of the hardest serves you have ever hit that you feel in your whole body down to your toes- and the damn machine shows 95 mph Yea...fun...

[CDestroyer]

Originally Posted by stoneage

You are measuring from the side, so the risk is minor
/Sten
______________________________________
racquetTune, swingTool and netHeight, tennis apps for the iPhone.

So whats the deal about the app only going up to 95 mph? Is that the limit or is the app not accurate? Please elaborate Stoneage.

[LeeD]

Oh C'mon, MofP, I'm the naysayer of all time, and I give you 130 as is, more if you tried to flatten it out.
And for comparison, I've been saying my serve is close to 100 flattened out, slower when hit with top/slice.

[luishcorreia]

Originally Posted by Laver777

lol, check out this app.... it can read the tension of your strings

http://itunes.apple.com/au/app/racqu...365729342?mt=8

There is also an app for android. I used it often. There are a lot of posts in the message board about this.

I have a post about it on my blog. http://online-tennis-blog.blogspot.c...r-racquet.html

[Chas Tennis]

Has anyone got any updates on measuring serve ball velocities with the video camera of a Smartphone?

This seems very feasible by simply putting in a scale to accurately get the distance along the ball's trajectory, make sure viewing angle is perpendicular to the ball's trajectory, etc. .

I did read that the frame rates of some smartphones can vary from 30 fps and not be reproducible. ? Test somehow?

100 MPH = 1760 inches/sec

In 1/30 sec a ball with a velocity of 100 MPH ball would travel

1760"/30 = 58.7"

Might be better to use a camcorder or DSLR with a more telephoto lens. But in bright sunlight I believe that many smartphone video cameras use a fast shutter speed that reduces the motion blur on the ball.

(It could be called the Pinocchio cam.)

[Limpinhitter]

Originally Posted by TheMagicianOfPrecision

I agree.

But this was just way off, imagine you hit some of the hardest serves you have ever hit that you feel in your whole body down to your toes- and the damn machine shows 95 mph Yea...fun...

You're probably comparing apples and oranges. Unless it captures the highest speed after contact, it's not doing what the radar guns on the pro tour are doing.

[Jazzy]

I know that when we used to put the $150 radar gun at the center of the net on the other side, there is a formula that you have to use as the pros is taken right off of there racquet and not until it gets to the other side of the net. I want to say it was around a .25 additional mph per mph. So a 95 mph serve would have around 23mph added to it. Hope this helps!!

[Chas Tennis]

(Not using the application in the OP but just any video camera.)

A smartphone or camera could catch the ball image from the side close to impact. You would need two frames along the trajectory any time after the ball is struck.

You need
1) a scale placed along the trajectory and videoed before or after the serve.
2) the time between frames (it should be 1/30 sec but it has to be checked?)

V = distance traveled / 1/30 second

It would be better to use a camera with a longer focal length lens and not have to worry whether the wide angle lens on a smartphone might cause some inaccuracy.