What 240 fps Shows That 60 fps Misses

At 60 fps each frame covers about 16.7 milliseconds. At 240 fps each covers about 4.2. Since the clubhead is at its fastest exactly where you most want to measure it, that four-fold difference decides whether impact, shaft lean and face angle are measurements or guesses.

Key takeaways

• 1 ÷ 60 = 16.7 ms per frame. 1 ÷ 240 = 4.2 ms. Four times the samples through the fastest part of the swing.
• At a driver clubhead speed of 40 m/s (about 90 mph), the head covers roughly 67 cm between 60 fps frames and about 17 cm between 240 fps frames.
• 60 fps frequently has no frame at impact at all. What you read off the nearest frame is interpolation, not measurement.
• Motion blur and rolling shutter degrade individual frames independently of frame rate — a fast frame rate helps both, but does not cure either.
• 240 fps fixes nothing about a bad camera angle, bad light or a cluttered background.

How much time does one video frame actually cover?

Divide one second by the frame rate. At 30 fps a frame covers 33.3 ms, at 60 fps 16.7 ms, at 120 fps 8.3 ms and at 240 fps 4.2 ms. Between two consecutive frames the camera records nothing at all, so everything that happens in that gap is lost.

That gap is the whole story. Video is not continuous — it is a sequence of samples with darkness between them. The question is never "is the video smooth", it is "how much swing happened while the camera was not looking".

Frame rate	Time per frame	Frames in a 0.25 s downswing
30 fps	33.3 ms	~8
60 fps	16.7 ms	~15
120 fps	8.3 ms	~30
240 fps	4.2 ms	~60

A downswing lasting a quarter of a second gives 60 fps about fifteen samples of the most consequential quarter-second in golf. Impact itself lasts under a millisecond. No consumer camera captures the collision — what you are actually trying to capture is the club arriving.

How far does the clubhead travel between frames?

Multiply speed by frame duration. Take a clubhead moving at 40 m/s, about 90 mph. In one 60 fps frame interval of 16.7 ms it covers 40 × 0.0167 ≈ 0.67 m — roughly 26 inches. In one 240 fps interval of 4.2 ms it covers about 0.17 m, close to seven inches.

Two-thirds of a metre is more than the whole meaningful impact zone. Between one 60 fps frame and the next, the club can go from clearly pre-impact to clearly past the ball, with nothing recorded in between. Whatever you conclude about the position of the shaft, the hands or the face at impact is a conclusion about a frame that was not impact.

At 240 fps, seven inches is still a lot of travel, but now several frames land inside the zone. You usually get a frame just before contact, sometimes one essentially at contact, and one just after. That is enough to see the club arriving rather than to infer it.

Run the numbers for your own speed if you like: distance per frame = speed in m/s ÷ frame rate. The 4× relationship between 60 and 240 holds whatever number you put in.

Why can you not measure shaft lean at 60 fps?

Because shaft lean is defined at a single instant — the moment the face meets the ball — and at 60 fps that instant almost always falls between two frames. You end up measuring the shaft either well before contact, when it is still leaning more, or after it, when the club has released.

Shaft lean changes fast through the strike. The whole point of the number is where the hands are relative to the clubhead at the ball, and reading it from a frame taken several inches early systematically overstates it. Read it from a frame several inches late and you understate it. Neither error is random, which is worse than noise: it biases every measurement in the same direction.

Face angle has the same problem, compounded. The face is rotating through impact as well as travelling, so a frame taken early shows a face more open than the one that struck the ball. A few degrees of face angle is the difference between a fairway and a tree line, and a few degrees is exactly what a 16.7 ms sampling error can hide. Why those few degrees matter is covered in shaft lean at impact.

What is motion blur, and does a higher frame rate fix it?

Motion blur is what you get when the subject moves while the shutter is open. Its length is speed × exposure time, and exposure can never exceed the frame duration. So a higher frame rate forces shorter exposures and shorter blur — but it does not remove it, because the club is still moving during the exposure.

Do the arithmetic. At 40 m/s with a full 16.7 ms exposure, the clubhead smears across roughly 67 cm of the frame. At 4.2 ms it smears across about 17 cm. Better by four, still a streak rather than a clubhead.

This is why the honest framing is that 240 fps improves blur rather than solves it. Cameras with genuinely short exposures — the strobe-style setups used in club-fitting bays — freeze the head properly. A phone cannot, and any claim that it does is marketing.

There is a trade you should know about. Shorter exposure means less light per frame, so high frame rate footage is darker. Filming at 240 fps in poor light gives you four times the frames and much less usable detail in each. Frame rate and lighting are one decision, which is why how to film your golf swing treats them together.

What is rolling shutter and how does it distort a golf swing?

Most phone sensors read the image out one row at a time rather than all at once, so the top of the frame is captured slightly earlier than the bottom. Anything moving quickly is recorded at different instants in different rows, which skews it. A vertical shaft moving fast can appear bent or leaning.

For golf this shows up as a shaft that looks subtly curved through the downswing, or a clubhead that appears displaced relative to the hands. It is an artefact of the sensor readout, not a fault in your swing, and it is one of the reasons a single blurred frame near impact should never be trusted on its own.

A faster frame rate usually comes with a faster readout, so the skew tends to be smaller at 240 fps than at 60. But it is a separate property of the sensor, not something frame rate guarantees. The practical defence is the same as for blur: read positions from the frames either side as well as the frame itself, and be sceptical of anything you can only see once.

What does 240 fps not fix?

Nothing about geometry or light. A camera off the target line still invents club path. A lens at the wrong height still fakes swing plane. A backlit golfer still has no visible hands. High frame rate makes a well-set-up shot far more useful and makes a badly set-up shot exactly as wrong, four times as often.

Three specific limits worth knowing:

• Resolution often drops. Many phones reduce resolution at their highest frame rate. More frames, fewer pixels in each.
• Light gets harder. Shorter exposures need more light, and indoor nets are the worst case.
• Storage and processing grow. Four times the frames is four times the data to record, store and analyse.

None of that is an argument against 240 fps. It is an argument for spending the first five minutes on camera position and light, and only then turning the frame rate up. Get both right and every measurement downstream — impact position, shaft lean, face angle, tempo — is real rather than inferred.

Where should you go next?

Frame rate is one of four setup variables, and it is the least useful one to get right on its own. The pieces below cover the rest of the camera setup, what a pose model can actually extract from those frames, and the measurements that a high frame rate finally makes trustworthy.

• How to film your golf swing — the pillar: angles, placement, lens height, distance, light.
• The 33 body landmarks pose estimation tracks — what gets measured in each of those frames, and where it breaks down.
• Golf swing tempo: the 3:1 ratio explained — a frame-counted measurement that gets sharper with every extra frame per second.
• Shaft lean at impact — the number that 60 fps cannot honestly give you.