OTHER: Sony A7 V
- Thread starter Peter C.
- Start date
NorBro
Major Contributor
One of the worst mistakes I've ever made early in my career - and one time, but it was enough to make a lasting impression on me - was ruin an entire day of slow-motion b-roll by accidentally having the shutter 1/50 while shooting 60p because you can't produce real slow-motion out of it.
It's a terrible option to have in any camera that is set to a video mode and recording 60p.
Any minimum shutter speed setting (what he briefly mentioned) should be ON by default (and internally programmed to behave like an angle even if it doesn't say it).
Anyway, thank you, and I don't know what you're exactly asking and can't confirm what he's saying from an engineering standpoint, but if 60p overheats at 1/60 and doesn't at 1/50 (if that's what really happened) then it's worth thinking about.
It's a terrible option to have in any camera that is set to a video mode and recording 60p.
Any minimum shutter speed setting (what he briefly mentioned) should be ON by default (and internally programmed to behave like an angle even if it doesn't say it).
Anyway, thank you, and I don't know what you're exactly asking and can't confirm what he's saying from an engineering standpoint, but if 60p overheats at 1/60 and doesn't at 1/50 (if that's what really happened) then it's worth thinking about.
Bassman2003
Veteran
I am not sure either. I have shot years of 60p at 1/60th that I slow down in post. I actually prefer it for dance etc... as the motion is smoother compared to a faster shutter. So I am not sure of the danger here. But I guess I am thinking of a normal filming preset + NLE and not Slow&Quick ? Overcrank...
cyvideo
Veteran
The old “Double the shutter speed to frame rate” stems from the film frame rate of 24 fps, where when film was projected at 24 fps it looked very jittery. That's because the persistence of human vision is around 1/20th of a second. As anyone who has shot and edited film would generally know. So you shot at 24 and projected at 48. Well, that was the conventional wisdom. Projecting each frame twice with a 180 degree shutter took you well outside the persistence of vision. This is why 25 and 30 fps TV was converted to interlaced transmission to give us 50i and 60i to smooth out motion to bring it closer to how the human eye observes motion. That is why for film, we projected at twice the frame rate. To smooth out movement.
With the advent of 50 and 60p video footage, it looks and perceptually delivers smooth motion. That is because long before the image is dying in your eye, about a 20th of a second, it is replaced with a new image every 50th or 60th of a second. The result, visually, delivers smoother motion.
If shooting at 50 or 60 fps, there is no 'real' need to double your frame rate by using a 180 degree shutter. Why not? For starters with a 180 degree shutter you lose a stop of sensitivity, And secondly, for me, from my observations when editing, the effects on movement in regard to motion blur. The first time I really observed the phenomena was years ago when 50p shooting became more popular. When I was editing a standup that had been shot outdoors. The presenter was a woman with long hair. The shoot took place on a windy day and her hair was flying around her shoulders a fair bit. But something look off about the hair movement. When checking the footage, I discovered it had been shot at 50 fps with a 100th shutter speed. This is what caused the flowing hair movement to look a little unnatural, as it was almost totally freezing the hair frame by frame. Virtually nil motion blur. A 360 degree shutter gives you a much more natural, smoother looking movement at a 50th or 60th with subtle movement. Further observations of footage over the years has confirmed this slightly unnatural movement is seen in various different shooting scenarios. Smooth but subtle movement has been rendered with a more jittery movement when using a 180 degree shutter when shooting 50 or 60p.
Chris Young
What I'm getting at it quite well explained here with vision examples:
Bassman2003
Veteran
Yes, I agree with Chris and have been preaching this on other forums for years. People get dogmatic about this 180deg rule and do not really take a look at the end footage enough to know why it is done in the first place. The 180deg rule represents a minimum shutter speed. 1/48th is about as slow as one can get away with for nice looking motion. For 60p it is optional to go to 1/120th.
As to what Gerald was speaking to, it is just a stupid quirk of still cameras not being properly morphed for video/film work.
As to what Gerald was speaking to, it is just a stupid quirk of still cameras not being properly morphed for video/film work.
Bassman2003
Veteran
Peter, to clean this up as I understand your question:
60p at 1/60th with give you all 60 frames per second. It is 60p at 1/50th that causes a mismatch within the camera. 60p at 120th is not needed, just a stylistic choice.