Does Repeat Rendering Affect Quality

dfred wrote on 3/3/2008, 11:25 AM
Many of you have read my various posts about a project I'm currently working on - loading video from DVDs of home movies and editing those to combine clips from various DVDs into one movie.

Someone suggested that I render my project from time to time and then when I go back into Vegas, to load that project and continue adding to it. Would this process cause any deterioration in quality of the video?

If so, is there a better way to save my file? I know I can load video into Vegas and save it and as I add more, I can hit CTRL+S to saving from time to time. I also know that a movie does not have to be rendered until one is ready to make a DVD (or email or whatever). I'm just trying to figure out the most efficient as well as effective way to save and work with an ongoing project.

Thanks.

Comments

tdebey wrote on 3/3/2008, 1:57 PM
From your description, it sounds like you are only reloading the "project' file, in which case you will not lose any quality.

If you mean to say that you render out to a file, such as foo.mpg and then reload that rendered file into you project, then yes, your quality will degrade each time you render and reload.
Chienworks wrote on 3/3/2008, 3:08 PM
Rendering, then continuing to add to your project has no particular benefit. I suppose if you have lots of effects and transitions then viewing a rendered version will give you a better idea of what the final project will look like, but it won't help make further editing the slightest bit more efficient. It also won't affect quality in any way, shape or form.

Now, if by chance you meant to say "go back into Vegas, to load that newly rendered file in place of what was on my timeline and continue adding to it", then that's a different matter entirely. This can speed up things dramatically as anything you've already rendered won't have to have things such as effects, titles, transitions, fades, etc. rendered again. It can lead to quality loss though. If you stick to a low-compression format such as uncompressed AVI or even Sony's DV AVI then the loss will be minimal.

Personally i don't bother. I just wait until the end and render it all at once.
dfred wrote on 3/3/2008, 4:27 PM
Actually, I've done both. I have saved a project file in Vegas and reloaded that project. I've also rendered a project and reloaded it and continud to add to it.

Chienworks brings up a good point - yes, I have rendered a project then loaded that "newly rendered file in place of what was on my timeline."

From reading the answers above, I guess either way is acceptable.

Now, currently I have about 5 minutes of my project, complete with titles and fades. When I "render as" from the "file" drop-down menu, if I select ".avi." in the box below that I see "uncompressed." Is this the box where I should be checking for compressed or uncompressed in my "render as" selection? May sound like a dumb question but I want to be sure this is correct before I proceed.

Last question - if I create the project with titles, transitions, fades., etc., and DO NOT render it, I just "save as" and give it a name and it's saved as a VF file. If I open that particular file, will all the titles, transitions, etc., still be there?

If so I'm good to go. If not then I'm thinking it'd be less stressful for me to render after each session.

I'm also thinking I should probably save a back up copy of my file, just on the chance either my internal or external hard drive crashes while I'm working on this. It may take me weeks to finalize this and I don't want to have to start from scratch again.
Chienworks wrote on 3/3/2008, 5:40 PM
The .vf file contains everything you've done on the timeline. It contains a list of all the clips, pictures, audio files, etc. that you've used. It contains all the edits you've done. It contains all the titles, generated media, effects, and so on. Save a .vf file, quit Vegas, shut down the computer. After you boot up again and start Vegas, load the .vf file and you'll be right where you were when you saved.

The .vf file does *not* contain video, audio, or picture files.