Frame Rate Question

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jeffnles1

jeffnles1

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OK, feel free to laugh. I'm an absolute novice with video and have a quick question about frame rate. My new Canon R7 can shoot 4K (and 1080) in 60, 30 and 24.

I believe (think,???) these frame rate numbers are how many frames per second the video is shot in. I do know some of the cool super slo mo stuff like a bullet going through a lightbulb are shot at several hundred thousand frames per second. I assume the higher the frame rate the more latitude for slowing it down? Not sure.

My question is of the 3 choices offered in my camera, why/when would I choose 24 vs. 30 vs 60?

Currently I have it set at 30 for no other reason than it was in the middle but I'm quite sure that is sub optimal

What are your thoughts / advice for a complete video rookie. I have been shooting stills for about 40 years so I'm quite familiar with stills terminology. Perhaps my difficulty here is trying to equate video language back to something I understand and there may not be a clear path in that direction.

Thanks, I hope my question made some level of sense.

Jeff
 
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jeffnles1 said:
OK, feel free to laugh. I'm an absolute novice with video and have a quick question about frame rate. My new Canon R7 can shoot 4K (and 1080) in 60, 30 and 24.

I believe (think,???) these frame rate numbers are how many frames per second the video is shot in. I do know some of the cool super slo mo stuff like a bullet going through a lightbulb are shot at several hundred thousand frames per second. I assume the higher the frame rate the more latitude for slowing it down? Not sure.

My question is of the 3 choices offered in my camera, why/when would I choose 24 vs. 30 vs 60?

Currently I have it set at 30 for no other reason than it was in the middle but I'm quite sure that is sub optimal

What are your thoughts / advice for a complete video rookie. I have been shooting stills for about 40 years so I'm quite familiar with stills terminology. Perhaps my difficulty here is trying to equate video language back to something I understand and there may not be a clear path in that direction.

Thanks, I hope my question made some level of sense.

Jeff
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Keeping it simple, 24 or 30 and shutter speed 1/50 or 1/60 (respectively). There is a slight difference in the visual impact between them, and I prefer 24.

Reserve 60 for slow motion, or if you need a faster shutter (which will be 1/120). Control the visual effect by choosing playback rate, 24 for slow motion and 60 for normal motion.
 
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Nimi said:
Keeping it simple, 24 or 30 and shutter speed 1/50 or 1/60 (respectively). There is a slight difference in the visual impact between them, and I prefer 24.

Reserve 60 for slow motion, or if you need a faster shutter (which will be 1/120). Control the visual effect by choosing playback rate, 24 for slow motion and 60 for normal motion.
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Thank you.
 
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So, I have a question for this group...what refresh rate are you running your display at...24Hz, 30Hz, 48Hz, 60Hz, 120Hz??? And yes, I know these are, in most cases, "rounded" timings.

Unless your display and the displays of those viewing your content are set to 24Hz refresh, why on earth would you shoot or render in 24fps and introduce judder in your content when it's displayed at any refresh rate that isn't an even multiple of 24Hz?

I shoot and render all my content in an even multiple of 30Hz...period. Unless you're producing content for theatrical release on a display device that will have a refresh rate of 24Hz or an even multiple thereof, stick to 30, 60 or 120Hz frame rates. Unless you're in a PAL locale, though in that case, I'd go with 25, 50, 100Hz frame rates.

It amazes me that I never hear this brought up...

Cheers!
 
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MotoPixel said:
So, I have a question for this group...what refresh rate are you running your display at...24Hz, 30Hz, 48Hz, 60Hz, 120Hz??? And yes, I know these are, in most cases, "rounded" timings.

Unless your display and the displays of those viewing your content are set to 24Hz refresh, why on earth would you shoot or render in 24fps and introduce judder in your content when it's displayed at any refresh rate that isn't an even multiple of 24Hz?

I shoot and render all my content in an even multiple of 30Hz...period. Unless you're producing content for theatrical release on a display device that will have a refresh rate of 24Hz or an even multiple thereof, stick to 30, 60 or 120Hz frame rates. Unless you're in a PAL locale, though in that case, I'd go with 25, 50, 100Hz frame rates.

It amazes me that I never hear this brought up...

Cheers!
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Most movies you watch are shot at 24fps and played at minimum on a 60hrtz tv. How much judder do you see there? Also of note 30 fps isnt actually 30fps its 29.97fps
 
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MotoPixel said:
So, I have a question for this group...what refresh rate are you running your display at...24Hz, 30Hz, 48Hz, 60Hz, 120Hz??? And yes, I know these are, in most cases, "rounded" timings.

Unless your display and the displays of those viewing your content are set to 24Hz refresh, why on earth would you shoot or render in 24fps and introduce judder in your content when it's displayed at any refresh rate that isn't an even multiple of 24Hz?

I shoot and render all my content in an even multiple of 30Hz...period. Unless you're producing content for theatrical release on a display device that will have a refresh rate of 24Hz or an even multiple thereof, stick to 30, 60 or 120Hz frame rates. Unless you're in a PAL locale, though in that case, I'd go with 25, 50, 100Hz frame rates.

It amazes me that I never hear this brought up...

Cheers!
Click to expand...
I have to find the article that explains that display refresh makes no difference to timeline fps. However, acquisition fps and timeline fps should be matched either by being the same or on exact multiple because of interpolation imperfections.

In my case (I don't shoot for fun), the timeline fps is typically dictated by client, and most frequently that's 24, sometime 30, rarely anything but.
 
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Wes, my comment about the timings I listed being "rounded" was meant to address that point without getting into typing out each one of the actual rates.

Display refresh absolutely has an effect when you have to map 24fps to a 30fps or 60fps display refresh...you see it all the time when watching pans or object motion on a TV and the interpolation causes a varying rate motion judder. The latest 120Hz displays can get by ok since they're a multiple of 24, 30 and 60. There are methods of interpolation in higher end displays, but the issue of having to drop or repeat varying numbers of frames to get to the desired display rate is still there and it's visible.

24fps is a practical relic of analog film days and while it does have its "look", I'm more than happy to put it up on the shelf along with my film cameras. I was involved in development and evaluation of prospective digital cinema projection technologies and one of the benefits that many in Hollywood and the exhibitors were excited about was not being stuck with 24fps film projection technology. Some had tried to move to higher frame rates with film over the years, but the reliability and the economics were just not practical to overcome. It was never a totally aesthetic decision to stick with 24fps and there are many feature releases that can benefit from higher frame rates.

For what many or most on this forum are shooting, it seems to me the 30fps and above is where we need to be for a whole host of reasons...in fact I'll likely be shooting anything that I might want cut to some SloMo in 120fps. It's not like we're burning through thousands of feet of film these days, though 2TB CFx cards aren't exactly chump change.
 
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Hi everyone. Thanks for your responses. I do apologize. I see Steve had a very similar thread posted and I did not see that before posting my questions. Sorry to post such a similar question. You all have been good in answering and much appreciated.
Jeff
 
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One of the things that I’m still not clear on and can’t really seem to find a good explanation is? Is it more advantageous to drop a Higher frame rate clip onto a lower rate timeline or just do like for like and let Final Cut Pro slow it down automatically? It seems to work just fine. Dropping a 60 frame for a second clip onto a 60 frame for second timeline and letting Final Cut Pro slow it down but I’m curious if it’s better, for example, dropping it onto a 30 fps timeline?
 
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Steve, like so many things, the answer is, "it depends". I use Davinci Resolve and generally I'm working with a 30fps timeline. It doesn't really matter whether I drop a 60fps or 120fps clip, or a mix of them on the timeline and I often do that if I'm shooting something I might want to slow down at some point. I have zero experience with FCP, but I'm sure others here can offer a comment.

My thinking is that it's always better to have more data than less data, as long as you have the means (storage and camera not overheating) to shoot the length of clip you want/need to. Obviously, shooting at a higher frame rate and using the same codec/image format is going to require twice the data storage. Are you possibly going to want to slow down some of the clip, SloMo, Speed Ramping, etc. Also, depending on your editing hardware and workflow, higher fps clips will have some impact on render times and general editing speed, scrubbing, transition and effects preview, etc. Basically, try it, see how it works on your hardware, it's not going to break anything.

Other than your time, it's obviously free to go out and shoot some tests and learn the impact of shooting and editing at different frame rates, different image formats, different resolutions, etc. Since late last Summer, I've been doing exactly that to get a handle on which Z9 video formats make sense for different situations...NRAW, N-log, 10-bit H.265, 8K, oversampled 4K, 2.3x crop 4K, 120fps, etc. There is no one answer and there is no substitute for getting out and shooting in all the different modes and learning where each one fits in your toolkit. And let's save which AF mode to use for another thread! :)

Cheers!
 
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MotoPixel said:
Steve, like so many things, the answer is, "it depends". I use Davinci Resolve and generally I'm working with a 30fps timeline. It doesn't really matter whether I drop a 60fps or 120fps clip, or a mix of them on the timeline and I often do that if I'm shooting something I might want to slow down at some point. I have zero experience with FCP, but I'm sure others here can offer a comment.

My thinking is that it's always better to have more data than less data, as long as you have the means (storage and camera not overheating) to shoot the length of clip you want/need to. Obviously, shooting at a higher frame rate and using the same codec/image format is going to require twice the data storage. Are you possibly going to want to slow down some of the clip, SloMo, Speed Ramping, etc. Also, depending on your editing hardware and workflow, higher fps clips will have some impact on render times and general editing speed, scrubbing, transition and effects preview, etc. Basically, try it, see how it works on your hardware, it's not going to break anything.

Other than your time, it's obviously free to go out and shoot some tests and learn the impact of shooting and editing at different frame rates, different image formats, different resolutions, etc. Since late last Summer, I've been doing exactly that to get a handle on which Z9 video formats make sense for different situations...NRAW, N-log, 10-bit H.265, 8K, oversampled 4K, 2.3x crop 4K, 120fps, etc. There is no one answer and there is no substitute for getting out and shooting in all the different modes and learning where each one fits in your toolkit. And let's save which AF mode to use for another thread! :)

Cheers!
Click to expand...
Yeah, I guess at the end of the day it’s like taking two routes to get to the same destination and you were right. It is a lot of trial and error to get things are the way you want it it is a lot of fun and I thoroughly enjoy learning. all I can about it.
 
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sh1209 said:
One of the things that I’m still not clear on and can’t really seem to find a good explanation is? Is it more advantageous to drop a Higher frame rate clip onto a lower rate timeline or just do like for like and let Final Cut Pro slow it down automatically? It seems to work just fine. Dropping a 60 frame for a second clip onto a 60 frame for second timeline and letting Final Cut Pro slow it down but I’m curious if it’s better, for example, dropping it onto a 30 fps timeline?
Click to expand...
You dont base the timeline fps on the footage, you base it on how many fps you want the final rendered video to be. Same goes for resolution. The footage fps is based on the desired look and need for slow motion. Im in the same camp as motopixel every timeline is set to 29.97 and the footage is usually shot at 120fps to be slowed in post. Almost all wildlife footage looks best slowed at least a little, even if its only 10%. Some people in the 24fps crowd actually shoot B-roll at 29.97 and play it at 24fps to slow down 20%.
 
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Wes Peterson said:
You dont base the timeline fps on the footage, you base it on how many fps you want the final rendered video to be. Same goes for resolution. The footage fps is based on the desired look and need for slow motion. Im in the same camp as motopixel every timeline is set to 29.97 and the footage is usually shot at 120fps to be slowed in post. Almost all wildlife footage looks best slowed at least a little, even if its only 10%. Some people in the 24fps crowd actually shoot B-roll at 29.97 and play it at 24fps to slow down 20%.
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Thanks for the reply and it was basically what I wanted to know. It seems to me like it would make more sense to drop the higher frame rate footage into a lower frame rate timeline but just wasn’t 100% positive. Thank you for answering that.
 
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A 1TB CFexpress card sells for roughly $350 but a 1TB SSD for use with a Ninja V sells for $60. For even 8K 60 fps video the SSD drives are fast enough.

I realize that this requires the intial investment in the Atomos Ninja but there are more than a few advantages of taking this route for audio and video capture. The Ninja V+ even handles 8K30 ProRes Raw or 4K120.
 
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