50i ou 25p ?

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@camelCased 8 жыл бұрын

Also don't forget that there are two factors in play here: 1) shutter angle when filming - for movie-like quality with slightly blurred image you should keep it to be 1/2* fps; that is - 1/60 for 30fps and 1/50 for 24 and 25 fps, see here: vimeo.com/blog/post/camera-settings-clarified-shutter-speed-vs-frame-r . This 2x (or 180 degree) relation is also claimed to most accurately replicate the human eye’s perception of the phenomenon known as “persistence of vision” and therefore provides the most natural-looking reproduction of normal movement. For sharp and crisp videos like TV news or sports you might use something else, like 1/90 or even less. Usually you might not want to use 1:1 (that is, 1/24 for 24fps) because it would blur the image somewhat, but in some cases it might be desired for smooth movements. This mode is sometimes referred to as "shutter off". If you go even lower (1/12), this will create smeared stuttering video like in bad night vision because the shutter will tick less than once per frame thus not catching up with capturing the full frame pixels. But take into account that shutter angle affects the exposure! If you go too low, you will get sharper movements but darker image and then you will have to raise ISO level which will introduce some noise. So, in dark environments you unfortunately might be forced to use 1/60 although you would like to use 1/90 to capture sharp movements. 2) fps and video file format - p or i, which is slightly different thing (I guess, it's called shutter speed), but the end result perceived effect might be similar to the one achieved while playing with the shutter angle. When using p (progressive) format, the end result can be controlled only by the shutter angle, as described above. But things get complicated when you combine together i (interlaced) video recording format with shutter speed - keep in mind that 50i at the end gives the same old 25 fps, thus the same rule as above - 1/50 for smooth and slightly blurred effect or 1/90 etc. for sharper, TV-like motions. But usually it is better to just use progressive (25p, 50p, 60p - whatever your camera supports) and then play with the shutter angle to achieve desired subjective perception (film-like, sharp or blurred). Progressive formats are in general easier to work with in video editors and they create less issues (jagged lines etc.). Interlaced is in general "a leftover" from CRT times and exists for compatibility with television broadcasting.

@chaldon2viewJ84M 10 жыл бұрын

Thanks for the info. I think your 50i looks the best. I have always used 25p but as my new camera has the choice of 50i would you recommend I use 50i?

@RE72900 10 жыл бұрын

It depends. 25p supposedly gives a cinematic look, but this is not obvious if you are using small sensor cameras (as I did in this video). Then, 50i is good enough for this type of camera.

@chaldon2viewJ84M 10 жыл бұрын

Rémi Gestalt Many thanks for your advice. I will try 50i on my next video.

@r.b.7632 5 жыл бұрын

50i est plus fluide mais l’Internet veut qu’on télécharge les vidéos en balayage progressif, mais les outils du désentrelacement existent. 50i is smoother but the internet wants that one uploads videos in progressive scan, but deinterlacing tools exist.