Serve Video Advice (3.0/3.5 w/ 120 mph - yes, while true I believe, that was to attract attention!)

[BA10S]

Hi,

I’ve not posted in the Tips/Instruction section before, but it’s something I’ve been wanting to do for some time.

So firstly, below is a link to the video. It is a side view and was taken using the slow motion feature of my iPhone 6 and uploaded to YouTube. It’s 30 seconds long and is just one flat first serve down the T from the deuce court.

Also, I live in Australia so we don’t have the NTRP rating system here, but I’ve watched a lot of videos and compared them to myself and local players who I compete at a similar level to. I can say with some confidence that I’m a 3.0 level player who’s at most 3.5.

So a few facts about my serve:

- The only strong evidence I have to back up my 120 mph claim is data from the Sony Tennis Sensor. I used a stock Steam 99S and my fastest serve reading was 195 km/h (121 mph) and on average was probably just under 180 km/h (112 mph). I’ve also used the Zepp 2 Tennis Sensor with the Insert Mount on a Blade 98 CV 18x20 and recorded a fastest serve of 189 km/h (actually 208 km/h (129 mph) including when the sensor detached!) and an average of around 175 - 180 km/h. I only used the Zepp sensor for a couple of serving sessions but used the Sony Sensor for much longer.

- My serve (overall, both first and second) is probably neither a weapon or a weakness at my level on average but can be vary a lot depending on how I’m playing.

- Both my 1st and 2nd serves severely lack consistency, accuracy and variety.

- I attempt a kick second serve virtually every time, but the amount of kick, spin and even pace vary quite a bit. My best 2nd serves can be quite effective at my level though and though slow can have a lot of spin and kick (not at all sure of the accuracy, but up to 4800 RPM according to the Zepp Sensor).

- I frequently make huge technical changes to my serve in the middle of matches when I’m not serving well - eg. pinpoint to narrow platform, dramatic changes to ball toss height etc.). I’m trying to break this habit, but it can actually help my timing sometimes.

- I regularly mishit my serve and send the ball well over the back fence!

I could write more, but I don’t think much else would be relevant. I practise my serve more than anyone I know and over the years have made many changes and have had a lot of ideas without making an improvement. It’s frustrating because I don’t think my serve has reached its potential and yet I haven’t been able to improve it. I’m lucky to be tall (6’2.5”) with long arms for my height (6’7” wingspan) and although I’m the furthest thing from a natural athlete I am lucky to have quite a ‘live arm’ and a pretty long, albeit very inaccurate and inconsistent, throw - I can toss a tennis ball, on a standard court with 21 ft (6 m) behind each baseline, standing as close to one fence as possible comfortably over the opposite fence. So I think my serve should be better than it is and I’d really appreciate any technical advice that you guys can give me because nothing I’ve tried seems to work.

Sorry about the long post by the way, I feel a bit narcissistic writing so much about myself, but I hope some of it helps those who choose to give advice. Also, I apologise if any of I wrote comes across as boastful, since that wasn’t my intention at all. I’ve trued my best to be as accurate and realistic as possible with all my claims and all of the information is included solely for the purpose of helping anyone who gives advice.

Thank you very much in advance, I’m very excited to read your responses!

 

[S&V-not_dead_yet]

I'd focus more on the accuracy and less on the speed.

You seem to be leaning quite far to the left. While I realize you're hitting flat down the T, that body alignment will telegraph the serve to your opponent.

Given your form, I expected to see your front/left foot come off the ground as you drove up into the serve but it stayed grounded.

Divide the service box up into 3 length-wise sections: wide, body, & T. Work on being able to hit your spots. Start with the 2nd serve that has more topspin and after you achieve good accuracy start throwing in the flat serve.

 

[J011yroger]

Greatest 3.0 serve on earth.

Makes me miss TTPS extra hard.

J

 

[Chadillac]

I never watch slo mo videos, sorry

 

[Chas Tennis]

There is too much motion blur. Repeat in bright sunlight so that your camera's automatic exposure control will select a faster shutter speed.

Pick a time and viewing angle so that shadows around the elbow will act as markers. You could also simply put some painter's blue tape on your upper arm between your shoulder joint and elbow. Markers are better. Three or four markers around your arm. For a bigger image, get closer until the camera bothers you. You should be able to see ISR directly from the shadows near the elbow.

Also, take a video of your serve from behind viewing along the ball's trajectory. This shows particularly the forearm-to-racket angle as the racket moves to impact.

I believe that most ATP players are not looking at the ball until impact occurs. But I know from videos that some are looking until impact. Karlovic, probably Tsonga. ? Most break off before impact but close to impact.

You break off very early compared to most ATP servers. The only strong server that I can recall that does that, and he is unusual, is Pat Cash. I believe, but don't know, that most servers break off earlier because it allows their upper bodies to bend forward more without neck stress. ? Some others like Stosur (sometimes or mostly) have their heads to the side somewhat like yours. Does she do that just for kick serves?......... Can she see the ball?

 

[Wesley J]

Look at the video. Pause at :25. Look at where you're looking. You said you mishit regularly? That's why.

 

[TheBoom]

+1 What Wesley J said

Push up and out with your feet, you barely get off the ground which means that you could be using your legs a lot more. The upper mechanics look fine but your lower body needs to be more engaged.

 

[rogerroger917]

120.... ok. 3.0. Crying over here from laughter. This place never ceases to amaze me.

 

[Topspin Shot]

Well you got my attention but you won't get any advice aside from nobody cares how fast you think you serve and make a proper video next time.

 

[Curious]

Based on the video it looks like 20mph!

 

[rogerroger917]

Tough crowd

 

[BA10S]

Thank you very much for all of your replies so far. I’ll be playing again tomorrow and I’ll make sure to take a much better quality video and upload it here. I’ll include a few more serves in better lighting from different angles and some close ups as well.

 

[joffa101]

I’ll include a few more serves in better lighting from different angles and some close ups as well.

Show some of the bad serves as well. No point showing us a ‘perfect’ serve if you can only hit 1 out of 10

 

[RetroSpin]

That's a very nice looking motion. If the rest of your game is similar, I can assure you that you are much better than 3.0/3.5. 3.0 is basically a beginner and 3.5 is a player who struggles to hit four decent rally balls and probably has a 65 MPH serve.

 

[Hmgraphite1]

Form looks very good. To start hitting spots you have to picture it in your head and start practicing. Pick the tee and start aiming for it without slowing things down. More leg drive, a lot more. It will happen if you keep practicing, I switch between pin point and narrow platform all the time.

 

[BA10S]

Show some of the bad serves as well. No point showing us a ‘perfect’ serve if you can only hit 1 out of 10

Excellent point, thanks, I’ll make sure to do that.

 

[jz000]

Just stick with a form that you can rely on for 3 sets without tiring out.
Serve like 10k balls and you'll start to feel like you have more endurance.
Take your time man, serves takes time.

 

[BA10S]

Just stick with a form that you can rely on for 3 sets without tiring out.
Serve like 10k balls and you'll start to feel like you have more endurance.
Take your time man, serves takes time.

Over the last few years I’ve hit a lot of serves. Many, many times I’ve gone out and served continuously for 3 hours or more. Even when serving at close to 100% on almost every serve I’ve never felt tired out (at the time, I usually sleep earlier due to feeling tired later on those days and the next day my back feels quite stiff). Actually my timing usually improves and my body loosens yo so that I’m hitting my biggest serves towards the end of the session. So I seem to have OK endurance (I’m only 20) but it’s my aerobic fitness that is extraordinarily poor - it’s so bad that I pretty much can’t have rallies of even moderate footwork intensity without getting extremely puffed out.

 

[jz000]

Well you are 6'2, that's 2 inches over me...
Maybe just do a relax serve standing still, hitting all the balls in.
Then go for 8/10 balls in using your legs a little...
And a little more.

But you gotta be able to swing 'up' so your feet are at least more than 1' off the ground
You have the right rotation of your right chest.. Just direct it 'up' towards the ball and you'll automatically be in the air.
Forget about topspin man, you are tall as f. Work on your 1st serve... ur 2nd serve can be a slice imo.

 

[BA10S]

Hi,

Sorry, but I played at night today and unfortunately the lighting wasn’t ideal for creating a better video of my serves. I did have a video taken of me hitting FHs during a baseline rally, and although my FH is my best shot it’s certainly far from perfect and I do make a lot of errors with it. I’d very much appreciate any technical advice you guys could give me on it. By the way, another thing worth mentioning is that as unnatural my serve can feel at times, my forehand never feels unnatural and I never think about my technique. As ugly and flawed as my FH technique is, it does feel natural to me and I’d really like to find a technique that feels the same for my serve. Anyway, here’s the video:

I welcome any advice you guys can give me. One thing I will say about my forehand is that I am incapable of taking the ball on the rise with my normal swing and I tend to let the ball drop far too low. I was wondering whether there was a technical reason for that or if it’s just a bad habit? Thank you very much in advance. I’m going to sleep now but I’ll check back in the morning.

 

[Power Player]

I played a 3.5 who said he served 120. He probably served 95 at best. Also, the serve went in maybe 8 times each set and his second serve was awful. So yeah, I think I gave him breadsticks and then bailed. The main thing I remember was that he kept talking about his serve like it was a huge asset. It was actually a negative. If he stopped thinking he was a big server and focused on hitting 80-90 MPH serves with nice placement and spin, he probably would be a much better player.

OP, that may apply to you.

Also, you are off balance on your ground stokes, but that's a pretty common issue. I still work on that a lot. I think it is one of the most important things to worry about when working on consistency. Most people here will focus on your swing and ATP/WTA..etc. I would personally ignore all that for now, but that's just me.

 

[BA10S]

I played a 3.5 who said he served 120. He probably served 95 at best. Also, the serve went in maybe 8 times each set and his second serve was awful. So yeah, I think I gave him breadsticks and then bailed. The main thing I remember was that he kept talking about his serve like it was a huge asset. It was actually a negative. If he stopped thinking he was a big server and focused on hitting 80-90 MPH serves with nice placement and spin, he probably would be a much better player.

OP, that may apply to you.

Also, you are off balance on your ground stokes, but that's a pretty common issue. I still work on that a lot. I think it is one of the most important things to worry about when working on consistency. Most people here will focus on your swing and ATP/WTA..etc. I would personally ignore all that for now, but that's just me.

You make some excellent points. Thank you. Like I said in my initial post, I don’t find my serve to be a weapon at the level I play and when I’m serving poorly it can be a huge weakness. My 1st serve percentage is extremely low and I lack accuracy as well as the ability to consistently hit with high pace (not at all due to physical reasons, but because my timing isn’t good). I do stand by my claim that my biggest serves approach 120 mph, even though I’m not a strong player. Not on average, but I’m quite confident of getting close to 120 mph when I’m serving my hardest. It means very little I know, but I’ve been told by several coaches that I serve at over 200 km/h. I don’t believe that though and acknowledge that people are prone to exaggeration, and think 120 mph is my absolute limit. As for my second serve, I hit tons of double faults but on a hot day the bounce I get on second serve does usually cause problems for the level of opponent I play against. My second serves often have a lot of RPM but are too slow (only around 60 mph I think!) and high over the net to be effective against stronger players. At the moment I don’t really have the technique to hit serves in between dead flat (most of my first serves) and pure spin.

And I completely agree that I’m very off balance when hitting most (in fact probably all) of my forehands. Part of the reason is probably poor footwork - I react late, don’t know how to split step and also don’t make small adjustment steps. I’ve also got a bad habit of hitting off the back foot, even when practising against dropped balls - which is inexcusable I know!

 

[gmatheis]

Your leg drive is too early, you are almost back on the court when you make contact with the ball.

Look at stosur's video someone posted above and see how her body is still rising when she makes contact.

 

[BA10S]

Your leg drive is too early, you are almost back on the court when you make contact with the ball.

Look at stosur's video someone posted above and see how her body is still rising when she makes contact.

You're probably right, but I know for sure that I don't get nearly as far off the ground as I should (and also that my left foot leaves the ground first, which as a RH server is the wrong order) and so that is another way of explaining why I'm hitting the ball while falling (and almost landing in the court!). It well be a combination of both though. In fact, I've seen quite a few of my serves on video in which I've actually foot faulted by landing in the court before the ball has left my strings! I've never been called on it, but it's definitely a big problem which my technique.

By the way, do you have any advice for my FH technique? The main issues I have are consistency and inability to take the ball early - this means I have to hit the ball closer to the lines to hit winners and I make a lot of errors as a result.

 

[Chas Tennis]

Serve speed -

The basic principle of measuring velocity is to measure the distance an object travels in a known time.

At 26 seconds there is a frame just before the ball is impacted. The ball is clear before impact. If you count out from the frame where the ball is clear 4 and 5 frames the blurred images of the ball can be seen against the house in two frames. Those two frames are a rough indication of the distance traveled.

This is not a perfect measurement because the ball is going away from the camera at some unknown angle, 5-15 d. ??, and the motion blur. This error can be estimated.

The distance traveled between frames 4 & 5 is very roughly ...........

Known time. What was the recording frame rate in frames per second?

 

[ChaelAZ]

I'd focus more on the accuracy and less on the speed.

This. Immensior this.

There are a few 3.5 players I hit with that have absolutely huge 100+ MPH serves, but the only spot they hit is towards the back of the serving box middle towards the T. All i do is fudge my positioning and stick a racquet out. I dropped my MPH years back and hit better spots with more variety, allowing more free points with good margin for error. Fastest I hit anymore is in the 90's. Most in the 80's, but I throw in some change-ups and 50 mph kicks.

 

[Hmgraphite1]

This. Immensior this.

There are a few 3.5 players I hit with that have absolutely huge 100+ MPH serves, but the only spot they hit is towards the back of the serving box middle towards the T. All i do is fudge my positioning and stick a racquet out. I dropped my MPH years back and hit better spots with more variety, allowing more free points with good margin for error. Fastest I hit anymore is in the 90's. Most in the 80's, but I throw in some change-ups and 50 mph kicks.

So the key is develop a high powered serve and then scale it back. This will result in exponential confidence and control.

 

[BA10S]

Serve speed -

The basic principle of measuring velocity is to measure the distance an object travels in a known time.

At 26 seconds there is a frame just before the ball is impacted. The ball is clear before impact. If you count out from the frame where the ball is clear 4 and 5 frames the blurred images of the ball can be seen against the house in two frames. Those two frames are a rough indication of the distance traveled.

This is not a perfect measurement because the ball is going away from the camera at some unknown angle, 5-15 d. ??, and the motion blur. This error can be estimated.

The distance traveled between frames 4 & 5 is very roughly ...........

Known time. What was the recording frame rate in frames per second?

Interesting - great idea. The recording frame rate was 240 FPS. I went back and looked at the original video and it is actually exactly 28 seconds compared to more than 30 seconds for the YouTube video - not sure why but it’s not relevant in this case.

Also I took screenshots at the frame just before contact (where the ball is clear) and (what I thought to be) 3, 4 and 5 frames after this point. I assume that the frames 4 & 5 that you were referring two are among these (since the frame after 5 the ball is outside the camera and the frame before 2 is on the racquet) I’ll attach the images here once I work out how and it might be possible to get a rough estimate of the distance travelled by the ball. Thank you very much for your idea. Certainly it would work better with a higher quality video from a better view with more view of the ball’s travel, which I’ll make sure to provide as soon as possible.

 

[BA10S]

https://imgur.com/a/CFzZB

Sorry that the photos don’t show up on the forum, but the link should work. The pictures, in order, are:

1. Frame just before impact
2. 3 frames after 1.
3. 4 frames after 1.
4. 5 frames after 1.

Estimating the distance the ball has travelled between frames 4 and 5 is not easy, so if anyone can help me I’d greatly appreciate it.

 

[ChaelAZ]

So the key is develop a high powered serve and then scale it back. This will result in exponential confidence and control.

Of course. Need to get int he 130mph range though before dialing it back though, least you just get less-than-exponential confidence and control. Maybe just small multipliers.

 

[mbm0912]

very pretty motion

 

[mbm0912]

Well you got my attention but you won't get any advice aside from nobody cares how fast you think you serve and make a proper video next time.

you should take notes from this serve, fella..

 

[Topspin Shot]

Hi,

Sorry, but I played at night today and unfortunately the lighting wasn’t ideal for creating a better video of my serves. I did have a video taken of me hitting FHs during a baseline rally, and although my FH is my best shot it’s certainly far from perfect and I do make a lot of errors with it. I’d very much appreciate any technical advice you guys could give me on it. By the way, another thing worth mentioning is that as unnatural my serve can feel at times, my forehand never feels unnatural and I never think about my technique. As ugly and flawed as my FH technique is, it does feel natural to me and I’d really like to find a technique that feels the same for my serve. Anyway, here’s the video:

I welcome any advice you guys can give me. One thing I will say about my forehand is that I am incapable of taking the ball on the rise with my normal swing and I tend to let the ball drop far too low. I was wondering whether there was a technical reason for that or if it’s just a bad habit? Thank you very much in advance. I’m going to sleep now but I’ll check back in the morning.

Hit through the ball, you're trying to spin it too much. That's why you're off balance and can't take the ball early. Also extend more to the target in your follow through before you finish across your body.

 

[Chas Tennis]

https://imgur.com/a/CFzZB

Sorry that the photos don’t show up on the forum, but the link should work. The pictures, in order, are:

1. Frame just before impact
2. 3 frames after 1.
3. 4 frames after 1.
4. 5 frames after 1.

Estimating the distance the ball has travelled between frames 4 and 5 is not easy, so if anyone can help me I’d greatly appreciate it.

Serve speed calibration -

1) To check that the scale is not changing between the frames on my computer screen of the frames to be used, I measured the distance between the two fence posts at the top of the white fence. I was getting two frames at 79 mm and one at 81 mm (OP arm in way) as displayed on my screen. The magnification does not appear to have changed between the frames.

2) The video shows that the camera was hand held and the camera pans to the right.

3) Because the camera pans we will measure from background objects, the downspout is good.

4) Motion blur smears the object edges in the direction of motion but not in the direction perpendicular to the motion.

5) The average tennis ball diameter is known, 2.57-2.70 inches or 6.54-6.86 cm and we can use it as a reference for length. Take average ball to be 2.63". In the frame before the ball is hit it measures 3.8 mm +/- 0.3 mm perpendicular to travel direction and more like 5 mm in the direction of travel with the motion blur added.

A mm scale is convenient for screen measurements.

Using the ball diameter to calibrate length on the screen at the location of the ball

2.63" / 3.8 mm = 0.69 "/ mm. (" abbreviation for inches)

In other words, 1 mm on my screen equals 0.69" in real space as recorded. Wide angle lens may vary magnification across the image, calibrate near the measurement. (The ball's image may be used if it is clear and has distinct edges, even a motion blurred image......)

6) Now we want to measure the distance between two frames.
Using your pictures #2 & #3 and using the down spout for "0" mm

Frame #2
The front blur is about 4 mm +/- 1 mm from the downspout (scale aligned with the ball's trajectory, slightly down).

Frame #3
The front blur is about 15 mm +/- 1 mm from the downspout (scale aligned with the ball's trajectory).

There is a problem in that when I look at the grey blur trying to get a measurement my eye play tricks with the grey level and they move. I estimated that uncertainty at +/- 1 mm. That estimate of the front edge could be much improved with better lighting.

The ball moved

15-4 mm = 11 mm between frame #2 and #3.

Using the screen calibration to get real space travel distance in inches
11mm X 0.69" / mm = 7.59" between frames #2 and #3.

7) The time between frame at 240 fps is

1sec / 240 f/ses = 0.0042 sec or 4.2 milliseconds

8) Velocity

7.59" / 0.0042 sec = 1810 " / second

One hundred miles per hour is 1760 " / second - a good conversion factor to remember for MPH.

1810"/sec / 1760"/sec X 100 MPH = 103 MPH

In this set up, since the ball goes away from the camera at a small angle the real distance traveled would always be greater than measured in 6) and the speed would always be higher from this correction. It is easier than correcting to move the camera to view more perpendicular to the ball's trajectory where you want to measure. First estimate is that if the trajectory goes away from the camera at 10 degrees the correction is to add cos 10 d to the measured length, or +2%. That would make the final measurement in this case, 105 MPH.

The edges of motion blur become smaller as the shutter speed becomes shorter in higher light levels. Better videos would increase accuracy.

The ball is a convenient length calibration but it has to be large enough and in good focus for accuracy. Distortions to the ball were ignored but heavy spin could cause errors. A better length scale or undistorted ball could be held in place before/after the serve and a length calibration recording done then.

[Conversions - if you type "X inches per second convert to MPH" or similar in the Google search box, Google performs and displays the conversion.]

 

[BA10S]

Serve speed calibration -

1) To check that the scale is not changing between the frame on my computer screen and the frames to be used I measured the distance between the two fence posts at the top of the white fence. I was getting two frame at 79 and one at 81 mm (your arm in way) as displayed on my screen. The magnification does not appear to have changed between the frames.

2) The video shows that the camera was hand held and the camera pans to the right.

3) Because the camera pans we will measure from background objects, the downspout is good.

4) Motion blur smears the object edges in the direction of motion but not in the direction perpendicular to the motion.

5) The ball diameter is known, 2.57-2.70 inches or 6.54-6.86 cm and we can use it as a reference for length. Take average ball to be 2.63". In the frame before the ball is hit it measures 3.8 mm +/- 0.3 perpendicular to travel direction and more like 5 mm in the direction of travel with the motion blur.

A mm scale is convenient for screen measurements.

Using the ball diameter to calibrate length on the screen at the location of the ball

2.63" / 3.8 mm = 0.69 "/ mm. (" abbreviation for inches)

6) Now we want to measure the distance between two frames.
Using your pictures #2 & #3 and using the down spout for "0" mm

Frame #2
The front blur is about 4 mm +/- 1 mm from the downspout (scale aligned with the ball's trajectory).

Frame #3
The front blur is about 15 mm +/- 1 mm from the downspout (scale aligned with the ball's trajectory).

There is a problem in that when I look at the grey blur to get a measurement my eye play tricks with the grey level and they move. I estimated that a +/- 1 mm. That estimate of the front edge could be much improved with better lighting.

The ball moved

15-4 mm = 11 mm between frame #2 and #3.

Using the screen calibration to get real space travel distance in inches
11mm X 0.69" / mm = 7.59" between frames #2 and #3.

7) The time between frame at 240 fps is

1sec / 240 f/ses = 0.0042 sec or 4.2 milliseconds

8) Velocity

7.59" / 0.0042 sec = 1810 " / second

One hundred miles per hour is 1760 " / second - a good conversion factor to remember for MPH.

1810" / 1760" X 100 MPH = 103 MPH

In this set up, since the ball goes away from the camera at a small angle the real distance traveled would always be greater than measured in 6) and the speed would always be higher from this correction. It is easier than correcting to move the camera to view more perpendicular to the ball's trajectory where you want to measure. First estimate is that if the trajectory goes away from the camera at 10 degrees the correction is to add cos 10 d to the measured length, or +2%. That would make the final measurement in this case, 105 MPH.

The edges of motion blur become smaller as the shutter speed becomes shorter in higher light levels. Better videos would increase accuracy.

The ball is a convenient calibration but it has to be large enough and in good focus for accuracy.

Thank you very much for your analysis! I certainly wouldn’t have been able to work all of that out myself and I very much appreciate that you explained the process so thoroughly - I’ll give it a try myself now. I’ll make sure to post a better video as soon as possible.

 

[5263]

Hi,

I’ve not posted in the Tips/Instruction section before, but it’s something I’ve been wanting to do for some time.


Thank you very much in advance, I’m very excited to read your responses!

you are falling into your contact, when you should strive to rise up into contact...

 

[vex]

Hi,

Sorry, but I played at night today and unfortunately the lighting wasn’t ideal for creating a better video of my serves. I did have a video taken of me hitting FHs during a baseline rally, and although my FH is my best shot it’s certainly far from perfect and I do make a lot of errors with it. I’d very much appreciate any technical advice you guys could give me on it. By the way, another thing worth mentioning is that as unnatural my serve can feel at times, my forehand never feels unnatural and I never think about my technique. As ugly and flawed as my FH technique is, it does feel natural to me and I’d really like to find a technique that feels the same for my serve. Anyway, here’s the video:

I welcome any advice you guys can give me. One thing I will say about my forehand is that I am incapable of taking the ball on the rise with my normal swing and I tend to let the ball drop far too low. I was wondering whether there was a technical reason for that or if it’s just a bad habit? Thank you very much in advance. I’m going to sleep now but I’ll check back in the morning.

You look like a homeless man's Jack Sock...

 

[BA10S]

You look like a homeless man's Jack Sock...

I think I’ve actually described it as a ‘3.0 Jack Sock FH’ before, but that description is so much better! Hilariously accurate! When even Jack Sock’s FH is often described as ugly, I don’t think a word even exists to describe how hideous my FH looks! It is a better shot that it looks I would say (I generate a lot of spin and pace for my level), but there’s lots of room for improvement.

 

[Chas Tennis]

https://imgur.com/a/CFzZB

Sorry that the photos don’t show up on the forum, but the link should work. ............

To post pictures from your computer to be displayed in posts - you need to first upload them to a photo hosting website following the website's instructions. Many are free but pick one that is likely to keep posting your pictures in the future. Photobucket, about a year or so ago, stopped posting many of the pictures in many posts from a few years ago, surprise!

Once pictures are on the website and displayed the proper size -

1) click on the picture
2) select "Copy Image Location".

Now get the Tennis Talk reply box and click on the icon at the top of the reply box that looks like a picture of two mountains and the moon. Paste the Image Location into the box.

Try "More Options..." lower right corner of the reply box. This should show you how the post will look when posted.

You can click on any picture from the internet and Copy Image Location. But don't copy location on copyrighted or other proprietary pictures. Most websites want more traffic and you could post their links.

 

[BA10S]

Hit through the ball, you're trying to spin it too much. That's why you're off balance and can't take the ball early. Also extend more to the target in your follow through before you finish across your body.

You’re definitely correct about me trying to spin the ball too much - almost all of my errors are mishits or shots where the contact is too thin and the ball slips off the strings and doesn’t even reach the net. I have no problem flattering the ball out, but the problem with that is I end up making even more errors overall. I think I end up flattening it out too much, but finding the right amount is hard. Also, a flatter shot would work better if I were to take the ball earlier, it’s low percentage when the ball is too low.

About extending through the ball, you’re also absolutely right. I’ve seen my forehand from the side and my lack of extension through the ball is even more apparent - to the extent where it is difficult to see any extension whatsoever. Strangely, and I’ve seen slow motion video which confirms this, even when I hit the ball dead flat I still seem to have no extension through the ball at all. I know I was hitting the ball dead flat because I was hitting as hard as I could against mid court dropped ball ‘sitters’ and had the Sony Sensor attached at the time and recorded a spin rating of only +1 or +2. I know this will cause controversy (though my intention is not to cause controversy but to show that the Sensor was overestimating and that @Chas Tennis estimate of 103 - 105 mph is more accurate) but when doing this I was recording FH speeds of around 175 km/h on average with a maximum of 181 km/h. Again, those measurements are clearly not accurate at all but I wanted to include them in order to demonstrate the inaccuracy of the Sony Sensor. I take back my 120 mph claim and now think that 110 mph is closer to the speed of my absolute fastest serves.

 

[BA10S]

To post pictures from your computer to be displayed in posts - you need to first upload them to a photo hosting website that hosts pictures following the website's instructions. Many are free but pick one that is likely to keep posting your pictures in the future. Photobucket, about a year or so ago, stopped posting many of the pictures in many posts from a few years ago, surprise!

Once pictures are on the website and displayed the proper size -

1) click on the picture
2) select "Copy Image Location".

Now get the Tennis Talk reply box and click on the icon at the top of the reply box that looks like a picture of two mountains and the moon. Paste the Image Location into the box.

Try "More Options..." lower right corner of the reply box. This should show you how the post will look when posted.

You can click on any picture from the internet and Copy Image Location. But don't copy location on copyrighted or other proprietary pictures. Most websites want more traffic and you could post their links.

Thanks, I uploaded those images to imgur from my phone but next time (I’ll take frames again from the next video of my serve) I’ll follow your instructions and use a desktop computer.

 

[Dan R]

Serve speed calibration -

1) To check that the scale is not changing between the frames on my computer screen of the frames to be used, I measured the distance between the two fence posts at the top of the white fence. I was getting two frames at 79 mm and one at 81 mm (OP arm in way) as displayed on my screen. The magnification does not appear to have changed between the frames.

2) The video shows that the camera was hand held and the camera pans to the right.

3) Because the camera pans we will measure from background objects, the downspout is good.

4) Motion blur smears the object edges in the direction of motion but not in the direction perpendicular to the motion.

5) The average tennis ball diameter is known, 2.57-2.70 inches or 6.54-6.86 cm and we can use it as a reference for length. Take average ball to be 2.63". In the frame before the ball is hit it measures 3.8 mm +/- 0.3 mm perpendicular to travel direction and more like 5 mm in the direction of travel with the motion blur added.

A mm scale is convenient for screen measurements.

Using the ball diameter to calibrate length on the screen at the location of the ball

2.63" / 3.8 mm = 0.69 "/ mm. (" abbreviation for inches)

In other words, 1 mm on my screen equals 0.69" in real space as recorded. Wide angle lens may vary magnification across the image, calibrate near the measurement. (The ball's image may be used if it is clear and has distinct edges, even a motion blurred image......)

6) Now we want to measure the distance between two frames.
Using your pictures #2 & #3 and using the down spout for "0" mm

Frame #2
The front blur is about 4 mm +/- 1 mm from the downspout (scale aligned with the ball's trajectory, slightly down).

Frame #3
The front blur is about 15 mm +/- 1 mm from the downspout (scale aligned with the ball's trajectory).

There is a problem in that when I look at the grey blur trying to get a measurement my eye play tricks with the grey level and they move. I estimated that uncertainty at +/- 1 mm. That estimate of the front edge could be much improved with better lighting.

The ball moved

15-4 mm = 11 mm between frame #2 and #3.

Using the screen calibration to get real space travel distance in inches
11mm X 0.69" / mm = 7.59" between frames #2 and #3.

7) The time between frame at 240 fps is

1sec / 240 f/ses = 0.0042 sec or 4.2 milliseconds

8) Velocity

7.59" / 0.0042 sec = 1810 " / second

One hundred miles per hour is 1760 " / second - a good conversion factor to remember for MPH.

1810"/sec / 1760"/sec X 100 MPH = 103 MPH

In this set up, since the ball goes away from the camera at a small angle the real distance traveled would always be greater than measured in 6) and the speed would always be higher from this correction. It is easier than correcting to move the camera to view more perpendicular to the ball's trajectory where you want to measure. First estimate is that if the trajectory goes away from the camera at 10 degrees the correction is to add cos 10 d to the measured length, or +2%. That would make the final measurement in this case, 105 MPH.

The edges of motion blur become smaller as the shutter speed becomes shorter in higher light levels. Better videos would increase accuracy.

The ball is a convenient length calibration but it has to be large enough and in good focus for accuracy.

[Conversions - if you type "X inches per second convert to MPH" or similar in the Google search box, Google performs and displays the conversion.]

Plus, it looks like that serve may have caught the frame. It certainly wasn't hit in the center of the racket. I can believe 120. Good looking motion.

 

[Dartagnan64]

Too much fussing about the speed of the serve and not enough fussing about the fact that the OP is looking at the ground on contact.

Keep your head up.

 

[RetroSpin]

About extending through the ball, you’re also absolutely right. I’ve seen my forehand from the side and my lack of extension through the ball is even more apparent - to the extent where it is difficult to see any extension whatsoever.

I really do not get all this concern about extension. What difference does it make after the ball is gone?

Now contact point is a different issue entirely. You want your arm out toward the net and in front of your body at contact but it is pulling across, not extending down the target line.

ps. Your Fh looks and sounds pretty impressive to me. Your footwork and balance could be improved however.

 

[vex]

I think I’ve actually described it as a ‘3.0 Jack Sock FH’ before, but that description is so much better! Hilariously accurate! When even Jack Sock’s FH is often described as ugly, I don’t think a word even exists to describe how hideous my FH looks! It is a better shot that it looks I would say (I generate a lot of spin and pace for my level), but there’s lots of room for improvement.

Hey, it just has to work!

 

[Chadillac]

You’re definitely correct about me trying to spin the ball too much - almost all of my errors are mishits or shots where the contact is too thin and the ball slips off the strings and doesn’t even reach the net. I have no problem flattering the ball out, but the problem with that is I end up making even more errors overall. I think I end up flattening it out too much, but finding the right amount is hard. Also, a flatter shot would work better if I were to take the ball earlier, it’s low percentage when the ball is too low.

About extending through the ball, you’re also absolutely right. I’ve seen my forehand from the side and my lack of extension through the ball is even more apparent - to the extent where it is difficult to see any extension whatsoever. Strangely, and I’ve seen slow motion video which confirms this, even when I hit the ball dead flat I still seem to have no extension through the ball at all. I know I was hitting the ball dead flat because I was hitting as hard as I could against mid court dropped ball ‘sitters’ and had the Sony Sensor attached at the time and recorded a spin rating of only +1 or +2. I know this will cause controversy (though my intention is not to cause controversy but to show that the Sensor was overestimating and that @Chas Tennis estimate of 103 - 105 mph is more accurate) but when doing this I was recording FH speeds of around 175 km/h on average with a maximum of 181 km/h. Again, those measurements are clearly not accurate at all but I wanted to include them in order to demonstrate the inaccuracy of the Sony Sensor. I take back my 120 mph claim and now think that 110 mph is closer to the speed of my absolute fastest serves.

Thats what i was gonna say, you touch the ball and start moving sideways, gotta give it like 4-6" entension upon impact then cross. Your also finishing way on the left side, keep your back foot planted so you dont spin so much.

Its hard to take the ball on the rise because your racket is only moving foreward for a split second

Look how much better the fh was with proper spacing vs when your feet were almost parallel. They call it the back foot for a reason

 

[Deleted member 23235]

Hi,

I’ve not posted in the Tips/Instruction section before, but it’s something I’ve been wanting to do for some time.

So firstly, below is a link to the video. It is a side view and was taken using the slow motion feature of my iPhone 6 and uploaded to YouTube. It’s 30 seconds long and is just one flat first serve down the T from the deuce court.

Also, I live in Australia so we don’t have the NTRP rating system here, but I’ve watched a lot of videos and compared them to myself and local players who I compete at a similar level to. I can say with some confidence that I’m a 3.0 level player who’s at most 3.5.

So a few facts about my serve:

- The only strong evidence I have to back up my 120 mph claim is data from the Sony Tennis Sensor. I used a stock Steam 99S and my fastest serve reading was 195 km/h (121 mph) and on average was probably just under 180 km/h (112 mph). I’ve also used the Zepp 2 Tennis Sensor with the Insert Mount on a Blade 98 CV 18x20 and recorded a fastest serve of 189 km/h (actually 208 km/h (129 mph) including when the sensor detached!) and an average of around 175 - 180 km/h. I only used the Zepp sensor for a couple of serving sessions but used the Sony Sensor for much longer.

- My serve (overall, both first and second) is probably neither a weapon or a weakness at my level on average but can be vary a lot depending on how I’m playing.

- Both my 1st and 2nd serves severely lack consistency, accuracy and variety.

- I attempt a kick second serve virtually every time, but the amount of kick, spin and even pace vary quite a bit. My best 2nd serves can be quite effective at my level though and though slow can have a lot of spin and kick (not at all sure of the accuracy, but up to 4800 RPM according to the Zepp Sensor).

- I frequently make huge technical changes to my serve in the middle of matches when I’m not serving well - eg. pinpoint to narrow platform, dramatic changes to ball toss height etc.). I’m trying to break this habit, but it can actually help my timing sometimes.

- I regularly mishit my serve and send the ball well over the back fence!

I could write more, but I don’t think much else would be relevant. I practise my serve more than anyone I know and over the years have made many changes and have had a lot of ideas without making an improvement. It’s frustrating because I don’t think my serve has reached its potential and yet I haven’t been able to improve it. I’m lucky to be tall (6’2.5”) with long arms for my height (6’7” wingspan) and although I’m the furthest thing from a natural athlete I am lucky to have quite a ‘live arm’ and a pretty long, albeit very inaccurate and inconsistent, throw - I can toss a tennis ball, on a standard court with 21 ft (6 m) behind each baseline, standing as close to one fence as possible comfortably over the opposite fence. So I think my serve should be better than it is and I’d really appreciate any technical advice that you guys can give me because nothing I’ve tried seems to work.

Sorry about the long post by the way, I feel a bit narcissistic writing so much about myself, but I hope some of it helps those who choose to give advice. Also, I apologise if any of I wrote comes across as boastful, since that wasn’t my intention at all. I’ve trued my best to be as accurate and realistic as possible with all my claims and all of the information is included solely for the purpose of helping anyone who gives advice.

Thank you very much in advance, I’m very excited to read your responses!

pretty solid number.
i've been using the sony tennis sensor, and the best i've gotten is ~98, (which seems inline with my playsite numbers)...
my avg (first) serve being ~90, with spin ~6.5
my avg (second) serve being ~70, with spin ~9
will be interested to see how your serve progresses as you improve your technique

if you're serving 129mph max... a better ratio would probably be 115 with heavy spin (will be about the same rhs, but will likely go in more often because of the shape you'll be able to give the ball).

 

[klaw]

Without videos of you missing it is hard to tell definitively.

Compare videos of yourself serving in and videos of you missing your serve. What is different? I suspect you have an inconsistent serve toss. Where is the ball relative to your body at contact? It should consistently be in front of you, above your right shoulder for flat serves and above your head for kick serves.

I had the same problem as you before. Alright serve motion but inconsistent serve. It improved drastically once I focused on getting the same ball toss every single time

 

[bitcoinoperated]

Serve speed -

The basic principle of measuring velocity is to measure the distance an object travels in a known time.

At 26 seconds there is a frame just before the ball is impacted. The ball is clear before impact. If you count out from the frame where the ball is clear 4 and 5 frames the blurred images of the ball can be seen against the house in two frames. Those two frames are a rough indication of the distance traveled.

This is not a perfect measurement because the ball is going away from the camera at some unknown angle, 5-15 d. ??, and the motion blur. This error can be estimated.

The distance traveled between frames 4 & 5 is very roughly ...........

Known time. What was the recording frame rate in frames per second?

I thought serve speed is measured as the ball goes over the net not right off the racquet strings?

 

[Deleted member 23235]

I thought serve speed is measured as the ball goes over the net not right off the racquet strings?

i always presumed it was off the racquet... that said never really spent much time figuring out the rule, as my serve is slow anyway