What is the MAX LENGTH I can burn on an SD DVD for PAL ?

[jowauk]

This is not a problem or issue - just a question seeking guidance from more experienced colleagues on this forum.

I film using a Sony Z1 series HD camera and get good results and quality. The work produced by VSX7 is really good - except for the apparent limitations of content duration that I can burn on a single DVD-R.

When I edit using VSX7 Ultimate I can never seem to get more than 70 minutes Project length to be acceptable for the burn stage. And on inspection of the burned DVD platter at 70 mins the surface looks to be burned well full.

Is it possible to maintain decent quality but get MORE content (say 1.5 or maybe 2 hours) on an SD DVD ? I know Blu-ray can hold more but I need to produce for SD playback in PAL format.

What drives the MAX LENGTH - is it a simple answer or do I need to go to college to grasp the variables ?

Are there any "smart" tactics I can adopt to get a longer duration on a single DVD (single layer - not interested in double layer).

Many thanks for any steer here - I have not yet got a real firm grasp of the key drivers for keeping highish quality whilst getting longer project length.

Regards

John

[Ken Berry]

The basic element which drives the size of a DVD is the bitrate used. In effect, the rule is that the lower the bitrate, the longer the video you can burn to a disc. But -- and there's usually a "but" -- there is a corollary rule which is the other essential element in deciding on how much you want to burn to the DVD, and that is that the lower the bitrate, the lower the quality. So essentially, the simple (?) answer is that you can burn quite a lot on a DVD using lower bitrates, but what is acceptable to you as quality might not be all that good.

Another thing you also need to bear in mind. A video DVD requires, by international standard, that the video be mpeg-2 with certain minimum properties. And mpeg-2 is not as highly compressed as some other more recent formats such as mpeg-4, DivX/XVid, MKV etc. It thus produces larger files. But there's not much you can do about that since, as I say, it is governed by international standard.

As a general thumbnail guide, you can burn -- as you have found -- around 70 minutes of DVD-compatible mpeg-2 to a single layer disc using the default high quality bitrate of 8000 kbps when you use Dolby audio -- a bit less if you use lower compression standard LPCM audio. You can also burn around 90 - 100 minutes using a lower bitrate of around 6000 kbps. The quality should still be good, but not as good as the 8000 kbps stuff. And you can burn around two hours using a bitrate of 4000 kbps, but the end quality will be probably no better than VHS tape.

In Share in VS X7, the DVD default bitrate used is 8000 kbps. Now, there are a couple of ways in which you can lower the bitrate and thus increase the length of video you can burn to disc. The first is the way a number of us here have learned over the years is perhaps the "safest" way. When you have finished editing, you can produce a new DVD-compatible mpeg-2 of your project by Clicking on SHARE but NOT going straight to the disc option. Instead, go to the first icon at the top right of the preview screen and click that (see image below).

That presents a number of different formats, but you need to pick MPEG-2. You will then see a little below a list of the Properties the new video will have -- and by default, as I have said, the bitrate will be 8000 kbps. To lower this, you click on the little pencil-like icon to the top right of the Properties box. A Dialogue box with three tabs, labelled Edit Profile Options, will appear. Choose the Compression tab, and go to the bitrate box and lower it from 8000 kbps to what you think you will need in light of the size of your project (as per the time guide I gave you above). You could also change the default "Constant" to "Variable" as this will give you a bit more wriggle room in the form of a little extra space. And if LPCM audio is showing, change that to Dolby. Then click OK to close the dialogue box, give your new file a name and click Start. Eventually a new mpeg-2 of your video will be produced which you can then test with a software player to make sure it matches what you wanted.

Then click File > New Project. Don't worry about a name -- the objective is just to clear the timeline of your existing project. Then select Share again, and this time the disc option -- clicking on DVD. The burning module will open but its timeline should be empty. Click on the first icon in the top left of the burning screen "Add Video Files" -- and select your new mpeg-2 which should then appear in the burning timeline. Then click on the *second* icon in the bottom left of the burning screen (the one with the cogwheel on it -- "Project Settings") and make sure the box beside "Do not convert compliant MPEG files" is ticked. Ignore the Properties box above it. Select your menu template, add chapters etc then burn.

The other way of doing all this would be to finish editing. then jumping immediate to the disc option in Share. When the burning module opens, your project file will appear in the timeline. Then click on that cogwheel icon in the bottom left and in the Properties box click on the "Change MPEG settings" button below the Properties box, and change the bitrate etc as set out above. Then click OK to close that "Project Settings" box, choose the DVD menu template, build chapters etc and burn. This method might seem faster than our preferred method, but in fact it is not. It also doesn't allow you to first test how your project looks when rendered to a DVD-compatible file. And long and hard experience also suggests to us that there are a number of other possible things that might go wrong if you use this seemingly more streamlined workflow.

[jowauk]

Ken - thank you so much for the explanation and in particular the clarity provided.

I can now see how I can at least experiment with the parameters to see what the final quality produced looks and sounds like. I can then make a decision on whether the compromises are worth the end result.

I am in the habit of always FIRST producing a video file from any Project, and then using that file in a "new" Project to burn to DVD. This habit goes back to X4 days when I regularly had VSX4 crashing when producing DVD's at the outer limits of the 70mins - very frustrating at the time and I have kept with doing it in 2 stages since then - only rarely seeing any such crashes. Probably the issues were the fragility of VS and maybe they have been fixed, but it has in the past cost me days of wasted time going through the process several times before getting a result. My edit hardware kit is fairly powerful and in my mind the issues were with VS capability once the project complexities (number of clips, transitions, sound path edits etc) get to hard for the software to handle.

Touch wood - now being on X7 (and having had the patches recently provided) it currently seems very stable.

Your help is greatly appreciated. Many thanks.

Regards

John