My project setting is 1920x1080x32. 25FPS I wish to make a standard def dvd.

The result will be very disappointing, despite the rendersetting you use. There is no best rendersetting for this aim, all are worse.

Hi J-V Vegas Pro 17. PAL

My project setting is 1920x1080x32. 25FPS I wish to make a standard def dvd.

The result will be very disappointing, despite the rendersetting you use. There is no best rendersetting for this aim, all are worse.

Hi 3 POINT. I have been making SD discs in other systems and been perfectly satisfied with the results.

Can you explain the problem with Vegas please

Hi J-V Vegas Pro 17. PAL

If you want to render that file for DVDA in your Vegas Pro you have to choose this default template

for the videopart and to this for the audio

In that case your projectsettings are much to high and can give problems with used texts and other MediaGenerators.
A self made PAL DV template for your projectsettings will do this job.
In that made DVD you will see a big quality loss if your sourcefiles are higher than PAL DV as @3POINT already stated.
 

Downscaling HD to SD is always disappointing (not only in Vegas) on the other hand downscaling UHD to HD is always satisfying. The main problem is that SD (DVD) is interlaced and and doesn't have the same PAR as HD. Creating DVD's from HDcontent is like copying an audio CD to an audio cassette, complete out of time to my opinion. 

Have made a couple of films and wish to make an authored dvd in DVD Architect.

A specific question deserves a specific answer.

Use the mpeg-2 DVD Architect Widescreen PAL template to render the video stream. Bitrate settings 2-pass, 9,000,000, 6,000,000, and 2,000,00 respectively. This will comfortably fit 90-95 minutes. You can relax the video ABR slightly to fit program to 4.35 GB, if necessary.

Use the AC3 Dolby DVD audio template to render the audio stream separately, but with the same name.

When you have opened the video stream in Architect, the audio will follow.

Happy Authoring!

@Musicvid's advice should be bookmarked by those of us who still use DVDs.

Here's the article Nick archived from the old SCS knowledgebase.

https://www.vegascreativesoftware.info/us/forum/scs-help-avoiding-recompression-in-dvd-architect--105496/

For those who still use DVD's and also need a bookmark how to render their project DVDA conform, take also a look at VegasMovieStudio where the creation of DVDAconform audio and video streams and sending them to DVDA is just a mouseclick.

For VegasPro, I can remember there was a free script DVDprep from VASST, which also was able to make a one mouse click DVD render, but I believe this script has not been updated for Magix VegasPro.

ps with DVDAconform I mean streams that are not recompressed in DVDA.

remark: I also remember that in those days where I burned DVDS (about 12-15 years ago), that there was a discussion about the better quality that was reached when DVDA self renders the necessary streams instead of rendering them in Vegas and sending them than to DVDA. But this I have never really tested.

For those who still use DVD's and also need a bookmark how to render their project DVDA conform, take also a look at VegasMovieStudio where the creation of DVDAconform audio and video streams and sending them to DVDA is just a mouseclick.

For VegasPro, I can remember there was a free script DVDprep from VASST, which also was able to make a one mouse click DVD render, but I believe this script has not been updated for Magix VegasPro.

ps with DVDAconform I mean streams that are not recompressed in DVDA.

remark: I also remember that in those days where I burned DVDS (about 12-15 years ago), that there was a discussion about the better quality that was reached when DVDA self renders the necessary streams instead of rendering them in Vegas and sending them than to DVDA. But this I have never really tested.