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As a beginner, how much importance should I give to the FPS feature of a camera? How is the price of a DSLR related to the FPS? Directly or inversely? I was under the naive impression that FPS was a term related to motion pictures... i.e., the rate at which you capture or playback a set of images.

How does fps relate (if at all ) to still photography?

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Different meanings of FPS. Yes, FPS is a measure of frame speed for video, but it is also a measure of the burst speed of a camera. Video frame rates are typically 24, 25, 29.97, 30, 60, 120, 240 or 480.

The FPS that is generally referenced when talking about still cameras is not the same. It is the number of full pictures that the camera can take per second. While a DSLR may be able to shoot 60fps video, it is only capturing around a 1 to 2 megapixel image when doing that, which is far less than the resolution of image the sensor can produce. The problem is that it takes time to move data from the sensor to the processor in the camera. So a camera that can shoot 24 fps video may only be able to shoot 8 fps of full 18MP images. Additionally, it can generally only shoot a certain number at a time (often somewhere between 7 and 50 total images depending on resolution and quality that is used. Do note that this can only be sustained for a short time though since once the fast cache in the camera fills, it takes more time to move the images to the memory card after processing. This is why burst can only be used for a short time before you have to wait for it to empty.

It doesn't have any direct relationship to the price of the camera as it is also dependent on the sensor resolution and different models may give it different priority. It might, for example, be possible to find a 12MP camera with 10 fps and the ability to shoot 19 full quality images at a time for less than the cost of a 22MP camera with the ability to shoot 8 fps and only store 17 full quality images at a time, but if you think about it, that actually makes sense since the 22MP images are much bigger than the 12MP images, so while the FPS may be lower, the 8FPS camera is actually moving more data.

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  • The data bottleneck isn't between the sensor and the processor. It is between the memory buffer and the memory card (or the bus that connects the two).
    – Michael C
    Sep 25, 2014 at 8:53
  • @MichaelClark so does that mean that the processor itself is the bottleneck? Sep 25, 2014 at 9:02
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    i don't see that, ml uses hacks which probably do not reach the full potential of the hardware. anyway, there are 3fps and 12 fps cameras out there, do you want to say the 12fps camera has a 4 times faster sensor readout?
    – ths
    Sep 25, 2014 at 17:11
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    @AJHenderson moore's law. Digital Cameras are computers. Computing power increases or cost decreases. You can move can a given number of bits faster per $ these days then when a 5d3 or a 6d came out. a 7d2 is a new generation. a 5d2 and 6d are old generation. 7d2 also has better AF and other features than a 5d3 ir 6d. time and specs both move on. sensor read out is not the problem at the moment. video reads the whole sensor then data is thrown away (pixel binning). The problem is card write speed. That's why we have a buffer. To allow us to capture data fast for a period of time.
    – Jason Tan
    Sep 25, 2014 at 20:06
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    @AJHenderson Sorry, it turns out that this is a thing in the dutch language only (bps = beelden per seconde = images per second), whilst we do use the english FPS for video. Hence my confusion.
    – Fer
    Oct 1, 2014 at 10:10
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Both.

It is of no importance for the genre of still photography, but it is or may be when you use "still" just to distinguish between photography and filming. The fps rate is of vast importance for some (or most?) sport photographers.

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    Thanks. Can you elaborate why it is not important to still photography but important in sports photography. Sports photography is a form of still photography, correct?
    – Victor
    Sep 25, 2014 at 14:49
  • The word still in the context of photography is ambigous. You may understand it to separate the photography of single photographs from filming - which is technically a long serios of individual photos with some reasonalbe fps rate. So for videos some rather high fps rate is a matter of quality until the fps rate reaches a level from which any higher fps rate does not bring any further improvement while watching the video. (High speed videography is different though) I understand still as still photography. Something like fc-foto.de/27034628 (cont. in next comment) Sep 25, 2014 at 19:54
  • For these stills the fps rate of the camera does not matter at all. I'd be happy with a fps rate of 1 or even lower. As a matter of fact, the reloading-time of the flash light acutally force me to less than 1 frame per second. So something well above 20 fps is probably ok and resonable up to 40 fps or so for regular videos (I am not a filmer, to be frank) Some or most sport photographers like to shoot series of individual photos (not videos) of a scene and choose later the best catch they made. For them a body with 6 or more fps (full size high quality photos) is much better than 3 fps. Sep 25, 2014 at 19:57

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