they keep falling on my head

[Tim Kolb]

This refers simply to frame numbering. (From your question, I assume you’re asking what drop-frame TC is…my apologies if I misunderstand your question.)

Due to a tedious-to-explain bit of NTSC history, the actual frame rate of American Television is just a bit below 30 frames per second.

However, one can’t number frames with the 30th being a 97% frame…they area all whole frames. Having 30 frame numbers a second, but running them slower creates a time deficit. 18 frames extra every ten minutes. The way that this is compensated for is that frame numbers 00:00:00:00 and 00:00:00:01 are “dropped” at the beginning of 9 of every ten minutes…this is drop-frame timecode.

It has little to do with encoding and shouldn’t affect speed or image quality at all.

TimK,

Kolb Productions,
Creative Cow Host,
Author/Trainer
http://www.focalpress.com
http://www.classondemand.net

[Norman Frizzle]

I understand the NTSC system.

Do I comprehend you correctly that the drop frame/non-drop frame distnction refers only to the timeline’s accounting for the NTSC system’s drop frame?

What advantages/disadvantages are there for the two?

[Steven L. gotz]

29.97 is the number. If you count frames in drop-frame, the amount of time it takes to play the clip is more accurate due to not counting certain timeslots. And when you have an exact amount of time between television commercials, this can be critical.

If you count 30 frames every second, eventually the timeline and the actual time eleapsed will be far enough off to cause a problem.

Either way …. the frames are all played. It is the accuracy of the elapsed time that is the issue.

[Norman Frizzle]

I understand all that. What I am asking is what is the difference between the options 29.97 drop frame and 29.97 NON drop frame? And what are the advantages and disadvantages of both? Presumably there’s a motivation for the user to choose one 29.97 option one over the other 29.97 option or PREMIERE would not offer the two, as distinct from its other options like 30 frames and 24 frame.

[Mike Velte]

Drop frame timecode “drops” frame number 00;02;00;01 and then one frame number every 2 minutes after that to create 30 frame numbers per second …just a scheme to work around the 29.97 thingy and stay sane.

[Tim Kolb]

[Norman Frizzle] “I understand the NTSC system.

Do I comprehend you correctly that the drop frame/non-drop frame distnction refers only to the timeline’s accounting for the NTSC system’s drop frame?

What advantages/disadvantages are there for the two?”

Now I’m unsure of your question…you say you understand the NTSC system.

Drop-frame TC is the basis of the NTSC frame rate.

Yes, it is only frame numbering. The advantage/disadvantage is that with drop-frame TC, when you reach the TC for one hour, it’s actually one hour into the show vs non-drop which would have you one hour, 3 seconds and 18 frames into the show at one hour of TC.

Many people who do 30 second spots run non-drop because the error is only 9/10 of a frame…but drop-frame is the standard for broadcasting for obvious reasons.

In corporate or event work, DF may be unecessary. Some users just find the idea of losing two frame numbers for 9 out of every 10 minutes odd, so they run non-drop.

Those are the principle advantages/disadvantages.

TimK,

Kolb Productions,
Creative Cow Host,
Author/Trainer
http://www.focalpress.com
http://www.classondemand.net

[Norman Frizzle]

I think I get it.

Now if I am using “non-drop frame” mode (as I note is the sertting I have in Premiere Pro). do I not run the risk of accidentally situating the first or lest frame of a clip on a ‘phantom’ frame and thus crippling my renders by introducing debilitating calculations to conpensate for the clip being out-of-synch?

[Tim Kolb]

[Norman Frizzle] ”
Now if I am using “non-drop frame” mode (as I note is the sertting I have in Premiere Pro). do I not run the risk of accidentally situating the first or lest frame of a clip on a ‘phantom’ frame and thus crippling my renders by introducing debilitating calculations to conpensate for the clip being out-of-synch?”

It shouldn’t, it’s strictly a numbering scheme and does nothing to speed, slow or otherwise affect renders…if it did, it would be some sort of an odd bug.

TimK,

Kolb Productions,
Creative Cow Host,
Author/Trainer
http://www.focalpress.com
http://www.classondemand.net

[Steven L. gotz]

I imagine Animators would probably be happier with Non-Drop Frame since they count frames more than seconds.

[Dave Friend]

[Tim Kolb] “the error is only 9/10 of a frame”

Isn’t the error actually 3/100 of a frame? (30.00 minus 29.97 = .03)

Dave