Precise cuts don't maintain accuracy when speed is changed at DVinfo.net

Glen Elliott · November 6th, 2003, 09:27 AM

I've found that precise cuts don't maintain their accuracy when the clip is slowed down. For example my source footage has a shot of a beach that cuts to a shot of a house. I zoom in really close (1:1..frame by frame) and splice the clip on the exact frame where the beach footage stops and the house footage starts (with quantize to frames enabled, mind you). If I use this house footage clip in between others in an edit I find, once rendered, the clip will retain a single frame blip from the beach footage that preceeded it on it's original clip. Yet I took extra care the cut was made precisely with not even a single overlapping frame from the footage prior to it. Why is this? Is this normal? Do you have to always go at least a few frames in on a new sceen to avoid getting overlapping frames from the last?

Edward Troxel · November 6th, 2003, 10:21 AM

So, you cut first and then slowed down? And now you say it has one additional frame?

HOW did you slow it down?

Glen Elliott · November 6th, 2003, 11:47 AM

Yeah cut it then slowed it down- via ctrl+drag.

Edward Troxel · November 6th, 2003, 12:16 PM

Can't say that I've seen that happen and couldn't quickly duplicate it. Even if it has happened, for me it would be the last frame of a dissolve an wouldn't be visible anyway (although it would certanly be visible on a "cuts only" program!). So, I don't have a quick answer for you other than trim it again.

Tor Salomonsen · November 11th, 2003, 03:17 AM

I'm guessing here.
Suppose Vegas is trying to match a certain number of frames to whatever your timeline is set to? Have you tried this with your timeline set to time and frames or absolute frames?

Glen Elliott · November 12th, 2003, 11:19 AM

Tor, I have the timeline set to 29.97 drop, and quantize to frames is enabled. Don't know if this is specifically what you were referring to.
It's odd because it doesn't show up when I'm reviewing the footage on the timeline. It's only after it's been rendered out to MPG1.

Tor Salomonsen · November 12th, 2003, 11:43 AM

Zoom in so that one second is about 1 cm. Press right or left arrow on the keyboard a number of times. Your cursor should move one frame each time you press, but not every time! Ever so often Vegas needs to take up slack. I suppose if you cut at one of these points you may get unlucky and end up with one frame too many.

Glen Elliott · November 12th, 2003, 12:08 PM

But would it only show in the outputted MPG1 and not in the preview window prior to rendering?

Tor Salomonsen · November 12th, 2003, 02:55 PM

With the approximation neccessary to make these things sum up right I suppose it's possible, but I do not know.

Rafal Krolik · November 19th, 2003, 03:51 PM

Glen. I run into the same problem and here is my workaround. I cut out a piece I want to slow down and render it to a new track. I than take the newly rendered clip and slow it down. So far it has always worked as planned.

Rob Lohman · November 24th, 2003, 08:50 AM

I think I've had this "problem" as well. In and out-points change
when speed is changed. Also I've had major problems when a
clip was reversed and I wanted to set in and out-points. Not
workable.

Edward Troxel · November 24th, 2003, 11:12 AM

<<<-- Originally posted by Rob Lohman : Also I've had major problems when a clip was reversed and I wanted to set in and out-points. Not workable. -->>>

It works just fine as long as you do the following:

Put the timeline at the END of the segment you want reversed and split at that point. Delete the part to the left and add the velocity envelope to the part on the right. Add the proper negative percentage and then find the proper end of the reversed clip.

DON'T trim and then reverse - reverse and then trim but START at the END.

Rob Lohman · November 24th, 2003, 12:40 PM

I'll try that and keep it in mind. Thanks Edward!

Joe Sacher · November 24th, 2003, 03:51 PM

One feature that would be very nice with velocity envelopes is to pin an event at a node. This would make all adjustments to the envelope pull or push video for the event, centered on that node. Sometimes with complex velocities on an event that needs to match for a cut, this would save considerable time. You would line up the clip, pin it, then adjust the edges and velocities.

November 6th, 2003, 09:27 AM	#1
Glen Elliott Wrangler Join Date: Apr 2003 Location: Philadelphia, PA Posts: 2,898	Precise cuts don't maintain accuracy when speed is changed I've found that precise cuts don't maintain their accuracy when the clip is slowed down. For example my source footage has a shot of a beach that cuts to a shot of a house. I zoom in really close (1:1..frame by frame) and splice the clip on the exact frame where the beach footage stops and the house footage starts (with quantize to frames enabled, mind you). If I use this house footage clip in between others in an edit I find, once rendered, the clip will retain a single frame blip from the beach footage that preceeded it on it's original clip. Yet I took extra care the cut was made precisely with not even a single overlapping frame from the footage prior to it. Why is this? Is this normal? Do you have to always go at least a few frames in on a new sceen to avoid getting overlapping frames from the last?

November 24th, 2003, 08:50 AM	#11
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	I think I've had this "problem" as well. In and out-points change when speed is changed. Also I've had major problems when a clip was reversed and I wanted to set in and out-points. Not workable. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

November 24th, 2003, 12:40 PM	#13
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	I'll try that and keep it in mind. Thanks Edward! __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

November 6th, 2003, 10:21 AM	#2
Edward Troxel Sponsor: JET DV Join Date: Dec 2001 Location: Southern Illinois Posts: 7,953	So, you cut first and then slowed down? And now you say it has one additional frame? HOW did you slow it down?

November 6th, 2003, 11:47 AM	#3
Glen Elliott Wrangler Join Date: Apr 2003 Location: Philadelphia, PA Posts: 2,898	Yeah cut it then slowed it down- via ctrl+drag.

November 6th, 2003, 12:16 PM	#4
Edward Troxel Sponsor: JET DV Join Date: Dec 2001 Location: Southern Illinois Posts: 7,953	Can't say that I've seen that happen and couldn't quickly duplicate it. Even if it has happened, for me it would be the last frame of a dissolve an wouldn't be visible anyway (although it would certanly be visible on a "cuts only" program!). So, I don't have a quick answer for you other than trim it again.

November 11th, 2003, 03:17 AM	#5
Tor Salomonsen Major Player Join Date: Jan 2003 Location: Stavanger, Norway Posts: 265	I'm guessing here. Suppose Vegas is trying to match a certain number of frames to whatever your timeline is set to? Have you tried this with your timeline set to time and frames or absolute frames?

November 12th, 2003, 11:19 AM	#6
Glen Elliott Wrangler Join Date: Apr 2003 Location: Philadelphia, PA Posts: 2,898	Tor, I have the timeline set to 29.97 drop, and quantize to frames is enabled. Don't know if this is specifically what you were referring to. It's odd because it doesn't show up when I'm reviewing the footage on the timeline. It's only after it's been rendered out to MPG1.

November 12th, 2003, 11:43 AM	#7
Tor Salomonsen Major Player Join Date: Jan 2003 Location: Stavanger, Norway Posts: 265	Zoom in so that one second is about 1 cm. Press right or left arrow on the keyboard a number of times. Your cursor should move one frame each time you press, but not every time! Ever so often Vegas needs to take up slack. I suppose if you cut at one of these points you may get unlucky and end up with one frame too many.

November 12th, 2003, 12:08 PM	#8
Glen Elliott Wrangler Join Date: Apr 2003 Location: Philadelphia, PA Posts: 2,898	But would it only show in the outputted MPG1 and not in the preview window prior to rendering?

November 12th, 2003, 02:55 PM	#9
Tor Salomonsen Major Player Join Date: Jan 2003 Location: Stavanger, Norway Posts: 265	With the approximation neccessary to make these things sum up right I suppose it's possible, but I do not know.

November 19th, 2003, 03:51 PM	#10
Rafal Krolik Regular Crew Join Date: Oct 2003 Location: Milwaukee, Wi Posts: 160	Glen. I run into the same problem and here is my workaround. I cut out a piece I want to slow down and render it to a new track. I than take the newly rendered clip and slow it down. So far it has always worked as planned.

November 24th, 2003, 11:12 AM	#12
Edward Troxel Sponsor: JET DV Join Date: Dec 2001 Location: Southern Illinois Posts: 7,953	<<<-- Originally posted by Rob Lohman : Also I've had major problems when a clip was reversed and I wanted to set in and out-points. Not workable. -->>> It works just fine as long as you do the following: Put the timeline at the END of the segment you want reversed and split at that point. Delete the part to the left and add the velocity envelope to the part on the right. Add the proper negative percentage and then find the proper end of the reversed clip. DON'T trim and then reverse - reverse and then trim but START at the END.

November 24th, 2003, 03:51 PM	#14
Joe Sacher Regular Crew Join Date: May 2003 Location: Indianapolis, IN Posts: 177	One feature that would be very nice with velocity envelopes is to pin an event at a node. This would make all adjustments to the envelope pull or push video for the event, centered on that node. Sometimes with complex velocities on an event that needs to match for a cut, this would save considerable time. You would line up the clip, pin it, then adjust the edges and velocities.