When I burn a DVD Toast always asks me if it should save a disc image. I always say yes, but yesterday I attempted to burn a new disc using a disc image as the source, thinking that it would save a lot of time. Toast Titanium however, informed me that the file was in the wrong format. Well, since it was Toast itself that created that file, whose fault was it that the file was in the wrong format? A rhetorical question of course; here's the real one: What use is a disc image?
Hi Eric, disc images enable applications etc. to be stored on non-apple format drives, even down to the lowly, and ubiquitous, memory stick. Try transferring a small app via one of these, and wait for the report of "corruption" etc. Unix and Windows don't co-exist well together.
Those innocent Mac application icons are actually collections of scripts and other stuff which are linked together. This is why clones differ from copies. Disc images are pretty much mini clones since they preserve the information structure. This makes them very useful for optical drive media transfers.
Data files don't need to use .dmgs, as they don't have to wrestle with scripts and structures in the same way. Music CDs generally, whereas multimedia DVDs present their well-known DVD chapter interface.
AHA! Thanks Euan;
The Wikipedia article made my brain hurt BUT: If I double click on a disc image Toast opens and offers to burn a DVD for me. I'm going to say "Yes" just for a laugh, and see what happens.
Eric, I've never used toast but if want several copies of a DVD (for example one made from iMovie), I use Disc Utility to make a disk image from the first DVD, then burn the other copies from this disk image, again using disk utility. Never had a problem but I can't say whether it works for all types of DVD.
Eric Jervis 