Multiple VSPs in project = poor quality

[Black Lab]

For the first time I tried using multiple VSPs (or nesting tracks as I think Media Studio Pro calls them) in a project.

It is a team highlight video, and I was creating separate 1 minute projects of each player that I would "nest" into my main project that consisted of the intro, music, and titles. I found this to be an easy way to do each player seperately. Following the Recommended Procedure I rendered the project to an mpeg. When I previewed the completed project it looked fine, albeit via the Instant Playback setting.

BTW, all the VSPs had the same project settings as the main project:
720 x 480
29.97 fps
LFF
DV Type 1
DV Audio NTSC
48.000 kHz, 16 bit stereo

However, upon viewing the finished DVD on my TV, the portions that were the nested tracks did not look as clear or as smooth as the intro (which was part of the main project). It wasn't that is was jerky, but it just wasn't the same quality as the intro. This was most noticeable during slo-mo action. Also, the audio at times sounded slightly distorted.

Having never had this problem before, and considering I tried a new method, I decided to try over again with the tried and true way. I rendered each of those separate VSPs to an avi file. I then added each separate avi in place of the corresponding vsp. I then created the mpeg then burned my project again. The result was clear and smooth motion (even the slo-mo) and the audio was also perfect.

So my questions are:

#1 Am I misunderstanding the procedure for using multiple VSPs, or nesting tracks, in a project?

#2 Has anyone else experienced this "problem"?

[daniel]

So my questions are:

#1 Am I misunderstanding the procedure for using multiple VSPs, or nesting tracks, in a project?

#2 Has anyone else experienced this "problem"?

#1 I'm afraid not !

#2 I'm afraid yes!
When I just insert two VSP on the timeline (like subsets of a single title, to improve editing responsiveness) then the resulting MPG is horrible, while the same VSP converted alone are OK.
In my case the most obvious problem is the field order looks reversed. The separate projects are lower-first, the combining VSP is also lower first, the Share step is "same as project settings", but the resulting MPG has transitions working backwards.
If I make two MPG from the subsets and combine them with a transition, using smart rendering the result is OK.
Of course this does not help is you wish to overlay the projects, not only join them.

[sjj1805]

Thanks for sharing the results of these tests.
The recommended procedures
1. By J.C. Hunter
2. By Myself

Are guidelines and not something written in tablets of stone.
What works for one user may not work for another user. They are intended to provide a new user with an initial workflow to get the first few projects off the ground. Once a new user gets the feel for what they are doing then - just like driving a car - they will develop their own way of doing things.

I am surprised at the results of these tests because one would expect there to be less deterioration when you have only rendered something once rather than several times. Black Lab is one of our more Senior Members and in fact does this for a living and so I respect the results published.

It highlights what I have stated in my version of the 'Suggested Workflow'

Failing to follow this or any other suggested workflow will not mean that a bolt of lightening will come shooting out of the sky and fry you and your computer. Experiment and find a workflow that works for you. This work flow works for me and follows a logical set of steps and provides me with a good result. It does not imply that you cannot do things in a different manner.

[jchunter]

I have not been tempted to try "nesting" projects because there is a simpler method that works every time: just create a video file (mpg) of every project and then select the whole lot in the burn module..

[Black Lab]

just create a video file (mpg) of every project and then select the whole lot in the burn module..

As I stated in my original post, I was trying the nesting feature because I had separate mini-projects that I was adding to throughout the season. Each of those mini-projects were to make up the final, whole project. Separately rendered mpegs inserted at the burn stage would not have worked in this instance.

[daniel]

I am surprised at the results of these tests because one would expect there to be less deterioration when you have only rendered something once rather than several times.

Just to be clearer, there is in my case no deterioration properly speaking, but a bug in the rendering, the fields looks to be swapped in the transition calculation (last case a stretch) when using VSPs on timeline.
I'm not 100% sure but it's the very same effect on TV as a field-order error, stepping and shaking movements.

And also rendering IS only once: the two partial mpg files.
The upper-level "concatenating" project is using smart rendering and of course all properties are the same. No re-rendering takes place, as is obvious given the speed of the create step.