Ideal fps Speed on Phone

If I buy a new phone, what is the ideal number of fps the phone should have as an option when recording for the best quality slow motion footage?

Are there any phones that keep the pitch of the notes the same when played back in slow motion as they are at regular speed. I don’t like it when the pitch lowers when played back at slow motion.

I believe that 120fps is the one to go for?

I have no idea about the slo-mo bit. Have you searches the forum? I’m pretty sure it has been mentioned a few times by Troy and Brendan.

This might help???

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Apparently the most recent iPhone (no Idea what that is called) can record with 240fps. Older version fo the iPhone already have 120fps. I have heard that the most recent Samsung phone (again, no Idea what the model name is) can also record with 120fps, maybe even 240 fps. Other than that it seems, that 60fps is more or less a standard now. I’m afraid that if you want 120fps or higher, you don’t have too many choices…

60 fps is fine for analysing technique. See my technique post where I used an iPhone 6s shot at 60 fps normal video mode. Then I used iMovie to slow the video down to 10% of original speed. iMovie allows you to keep the original pitch even at 10% of the speed. For me the most important factor is good lighting. Have as much light as possible and you will get good results. 60 fps is ample with good lighting.

If you film in slow motion I think you don’t get to record audio? Is that correct? But filming normal speed then slowing down gives the audio then you don’t need to sync it up.

Honestly, that clip was a little rough in 60fps. I mean nothing negative, and as always I thank you for posting that. Any time we get to see technique it’s a privilege.

However speaking purely technically, if I have to look at slow motion video I prefer 120fps for the following reasons:

  1. Anything slower than 120fps doesn’t provide the enough temporal detail to see smooth movement when slowed down past 50%. 120fps means you can slow down to 25% for perfect smoothness and 20% is still perfectly acceptable since it’s comparable to the cinema (24fps) or euro PAL (25fps) rates.

  2. Motion blur. A 1/60 shutter is not fast enough to freeze motion. A fast moving picking hand will still be blurry when played back slowly.

  3. Rolling shutter. Sometimes referred to as “jello cam”, where images appear to stretch and unstretch vertically or horizontally. It is caused by the phone reading the image sensor row by row, during which time the subject moves. The resulting image appears distorted in the direction of the sensor readout. You can see this in your 60fps clip where it almost appears like the hand is being viewed underwater or through a gel. This is a limitation of the sensor tech and there is no way to control it directly. Filming at 24, 25, or 30fps is the absolute worst for rolling shutter, and slowed-down video of moving objects usually looks terrible. However, when filming in 120fps, the phone uses a smaller portion of the sensor which scans faster, so the object doesn’t move as much during the scan. Images look far less distorted, and are not as fatiguing to try and follow with your eye if you have to look at them for any length of time.

Why not 240fps?

In 240fps mode, most phones use a line-skipping algorithm so they don’t have to capture every pixel. As a result, straight lines can look jaggy and pixelated. The effective data rate per frame is also reduced. Because of the greater number of video frames, each image is essentially a worse quality compressed image, like a really small sized jpg.

Combined with the much greater light requirements (8 times more than regular video!), we only use 240fps when it is absolutely necessary for filming very fast things, like hyperpicking, or things that have lots of motion blur, like strumming.

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