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Hello...
In the ARRI sequence preset, there is are Timebase options of 29.97 and 30.
If you choose 29.97, you can specify a display format of 29.97 Non-Drop.
And if you choose 30, it has a display format of 30.
Is there a difference, between them?
I would think that 29.97 non-drop and 30 would be the same.
Personally, when I'm doing a 30fps project, I like seeing 30 (not 29.97).
I'm not working on something for broadcast, but computers.
I'd rather use ARRI 30, just for the visual framerate confirmation (don't have to be concerned about it getting switched to drop frames, accidentally).
JJ
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Drop and Non-Drop refer to Timecode only.
29.97 and 30 refer to the Frame Rate.
There is a difference between Frame Rate and Timecode. There is a difference between 29.97 and 30 fps Frame Rates.
Choose correctly.
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Drop and Non-Drop refer to Timecode only.
29.97 and 30 refer to the Frame Rate.
There is a difference between Frame Rate and Timecode. There is a difference between 29.97 and 30 fps Frame Rates.
Choose correctly.
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29.97 drop frame is used in broadcast to ensure a proper duration indication
if you use non-drop frame TC you will be ~4 seconds too long when you get to the 1 hour indication
1st rule is typically to pick the frame rate that matches your source footage
if all your source material is generated in PrP (just text, bknds etc.) then pick any frame rate you prefer
2nd rule is typically to match your time code to the frame rate
if you're using 29.97 or 59.94 then you have to decide if a accurate duration indication is necessary
of you don't care about exact duration, pick any TC rate you prefer
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Qengineering wrote
29.97 drop frame is used in broadcast to ensure a proper duration indication
if you use non-drop frame TC you will be ~4 seconds too long when you get to the 1 hour indication
I was specifically asking about 29.97 NON-drop frame versus 30.
Is there any difference, between those two?
JJ
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Fa310tx wrote
I was specifically asking about 29.97 NON-drop frame versus 30.
Is there any difference, between those two?
Yes, the choice of drop or non drop timecode is only available for a frame rate of 29.97.
If you choose to edit with a frame rate of 30fps, you will only have 30 fps timecode as the available option.
It seems to me that you are confused between the timebase of the sequence and the type of timecode that you should use with your choice.
In you original post you should source files that were all shot at 29.97. Why you would want to edit at 30fps is a mystery to me.
As Qengineering
has already posted, if you edit at 29.97 fps you have two choices of timecode. You would use Drop Frame timecode if you are targeting an exact edit duration greater than 10 minutes. If you don't need to hit a specific show duration, or are editing something like a :30 second tv commercial, I would choose Non-Drop code.
But it's your choice.
Note:
Drop Frame timecode is called drop frame timecode because it adjusts the timecode numbers automatically, it does not drop any video frames.
Here's a link to more guidance:
https://blog.frame.io/2017/07/17/timecode-and-frame-rates/
MtD
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As MTD indicated the main difference is in the time-base,
obviously they count frames at a different speed.
Both count sequentially without any skipped numbers but 30fps TC in a 30 fps sequence will accurately indicate elapsed time,
29.97fps non-drop TC in a 29.97 fps sequence will NOT accurately indicate elapsed time.
You can not use (force) 29.97 fps TC in a 30 fps sequence, nor can you use (force) 30 fps TC in a 29.97 fps sequence
Review rules 1 & 2
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Also, if you chose to place 29.97 footage into a 30 fps sequence (don't even think of doing this with interlaced footage) your progressive frames will have a duplicate approximately every 30 seconds (the same frame will be used twice on a row), this is to adjust for the non-matching time base.
If you're good with that, go for it.
Most editors would cringe at the thought of doing that simply because they like to see '30' instead of '29.97'
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I have tried for years to understand this stuff and still don't. Probably as I don't use it.
I am glad we only have 25 and 50.
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The other factor is if you need the video to be in sync with audio or caption files staying in sync. The drop frame characteristic must match.
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It's all the sound departments fault that we have 29,97fps anyway.
When converting to colour in the fifties it was found that when adding the colour signal to a 30fps b and w picture it interfered with the sound so they just tweaked the sub carrier frequencies until the interference went away. This pushed the framerate to 29.97. Lucky in Europe we had no problems with 25 fps
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Qengineering wrote
Both count sequentially without any skipped numbers but 30fps TC in a 30 fps sequence will accurately indicate elapsed time,
29.97fps non-drop TC in a 29.97 fps sequence will NOT accurately indicate elapsed time.
Why is there even a non-drop frame timecode option, then?
That's what didn't make sense, to me.
If 29.97 is, inherently, drop-frame, then 29.97 non-drop frame should be the same as 30.
I didn't think about the software simply duplicating frames, to make up the difference.
I guess you could use some kind of interpolation, but I see why having your sequence match your footage is important.
The issue is that I have a mixture of videos, from different cameras (24, 29.97, 30, and variable).
My brain just kind of goes to 30fps, since I do screencast stuff and everything ends up as internet videos (not broadcast).
Given that information, I would be inclined to output 30fps.
Would it be even better to output to 29.97, even though it wouldn't be used for broadcast?
It seems that sites, like YouTube, would prefer 30fps.
JJ
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29.97 has been around a LOT longer than the web and YouTube.
Most of the content my company puts up on the web is 23.976 fps (not 24 fps)
24 fps is a film rate, as-in Hollywood and film (acetate) projectors
23.976 was adopted, just like 29.97 vs 30 fps, to accommodate color TV broadcast requirements
(4 frames of 23.976 fits into the time of 5 frames at 29.97)
Non-drop can be utilized for people doing short form (<1 minute) broadcast and who don't want the confusion of "what the heck happened to the frames at TC 1:00:00 and 1:00:01?" (drop frame eliminates those numbers)
I do mostly broadcast commercial work, I use non-drop 95% of the time
I edit and Master at 23.976 then export and deliver at 29.97
29.97 non-drop is not inherently 30 fps, it displays frames slower than 30 fps and that is because it was necessary for color TV development.
Along comes digital video and the internet and now you can have any frame rate you like, even variable.
With today's technology 29.97 is no longer required for broadcast, but I'll let you be the one to tell the stations to throw out all their gear and switch to 30 fps, never mind their archive libraries...
Edit and output what ever you like,
be aware of the anomalies of mixing frame rates
if you never deliver to broadcast, no one will ever care
YouTube makes NO frame rate preference that I am aware of, but lower frame rates compress better than higher frame rates.
29.97 vs 30 would make no visible difference in compression
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If you want a suggestion on what YOU should do,
look at one of your completed edits, determine what frame rate constitutes the majority of your finished content and edit at that frame rate. This will result in the least amount of frame rate mis-match anomalies in your delivered content.
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I agree with Ann Bens. I have no clue what's going on.
But I've managed to blunder through life and "guess" at stuff and come up with science fiction fantasy explanations for things. For example, why do dogs dig holes in the yard ? I have a theory !
Why is there 29.97 ?
Broadcast TV couldn't send full frames over the air ( via antennas) and guess what ? They STILL CAN'T ! So they sent half frames ( 2 half frames = one whole frame ) and it called 'intererlaced' or something like that. Even though the signals are now digital instead of analog, they still can't send the full frame. I know I have an antenna on my roof. I have a flat screen TV now instead of an old CRT TV. My silly flat screen (16:9) TV can magically turn the interlaced antenna signal into FULL FRAMES internally. I don't get those old horizontal lines of interference that the old CRT TV used to get if reception is not good. Now it just goes blank if the signal gets weak.
The old TV worked on the electric grid in the U.S. which is 60 cycles per second. The little electron gun inside old TV's ( run by an electro-magnet ) shot electrons from the back of TV to the inside of TV screen, illuminating ( magic ! ) the little pixel things which made an image visible.
The magnet worked on 60 cycles per second, which meant that half frames could be detected at 30 FPS. In Europe they got different grid.
The 720x480 screen size of old TV had even lines and uneven lines ( fields, called upper and lower). So the little electron gun would shoot stuff out to the inside of TV screen, doing uneven lines first and when the gun thing got to the bottom it had to get info ( kinda like meta data ) to tell it to " GO Back up to the top and start shooting stuff on the EVEN lines ! " " Hurry up, or else nobody will like you ! "
That last line of "info" ( according to my Sci Fi theory ) is why it boils down to 29.97 instead of 30.
There is some over-scanning involved with broadcast ( like, some pixels on sides get cropped) and maybe that's what goes on with Europe for the meta data on their crazy elec. grid system for the bottom of the fields of their old TV's. I have no clue.
If you told all the TV stations to stop sending over the air signals, which would make me have to buy cable TV, I would hate you !
So, don't even think about it !
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stupid computer won't let me upload a picture I drew...illustration of scanning fields...maybe later.
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With regard to the 23.97 I have another science fiction theory. Namely, it has to do with converting from 24 to 30 broadcast, using digital, and using timecodes or something.
Film cameras shot 24 ( or other FPS) but not fractions. Projectors in theatres showed 24 fps. Simple.
Now, with digital, why NOT have 23.97? I mean, basically ( in my science fiction world of theories ) we know that you have to add 6 frames to go from 24 to 30. A duplicate frame has to be made every X number of frames ( evenly divided so we don't notice it ) to go from 24 to 30. So why not include 23.97 to match time code of 29.97 ?
However, I admit, I don't really get it but am making this up just to sleep more soundly.
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