How to burn large videos to DVD on iMac

I burn iMovies all the time but you need a rendering app like Roxio Toast which will make the DVD readable on a DVD player. You can burn HD or Blu-ray as desired.

Depends on how you are trying to burn it exactly.

An uncompressed iMovie video file would likely be too large to fit in a Dvd that can only hold 4.5GB of data.

But compressing it and burning it as a video DVD (playable in any DVD player) rather than a Data DVD (accessible on a computer only) may allow you successfully burn it to a DVD.

Macs no longer come with a DVD authoring software beyond the basic data burning in Finder.

Yes, you would need a 3rd party software to create an actual DVD, playable on any dvd player.

https://www.roxio.com/en/products/toast/

The software does not get to limit how long a movie can be when burned on a DVD.

DVDs normally accept 4.5GB of data or (and this will depend on video compression) more than 3 hours of video at the traditional 720p of DVDs. Assuming you want it to play like a comercial movie DVD on any DVD player.

Again, this has nothing to do with the software you choose to use, its a standard of the DVDs not the software. Whoever at Cisdem told you 50 minutes has no idea what they are talking about.

If you need it to stay at a higher quality, like 1080p, then 2 things will need to happen. 1, it will not play like a traditional DVD movie on any DVD, it will be a data disc, and 2. You will be limited to a 4.5GB file size.

What is the end use of this DVD? Does it really need to work like a traditional comercial movie DVD?

Where is the DVD going to be accessed?

I have no experience with Cisdem, but I believe they only offer 1 DVD burning software, the aptly titled "DVD Burner"

The free Burn.app should make it easy...

https://sourceforge.net/projects/burn-osx/

Played back on a TV how?

What are you going to be using to play it back on the TV?

Again, do you expect it to work like a traditional movie DVD? Just stick it in and it starts playing and shows a menu?

Or do you expect to see a bunch files and select them from a finder or file explorer-like interface?

Can your DVD player access data DVDs? (make and model would help to determine this)

If you are trying to get a DVD with menus and instant playback like your comercial movies, rather than just see files on screen, then you need a DVD authoring software so you can create the DVD and menus to access the videos and photos.

If you just want it to be a collection of files, and your DVD player can access those types of discs, then you can do so without a 3rd party app.

You need to clarify what it is you expect out of the DVD. How are you envisioning you will access this on your TV exactly?