Can't burn to DVD+R DL

Seems as if I should be able to, but K3B in my Fedora 33 VM says it can’t burn 9.2G into 9.4G of blank space. Anyone know?

A dual layer DVD only has 8.5 G of usable space. Recommend burning it onto a 16GB (or larger) USB instead, which is what I did. BalenaEtcher is a good Linux program to use to do this. You can find it here: balenaEtcher - Flash OS images to SD cards & USB drives

So, K3b lied to me? How rude. I wonder what it will do with a blu-ray disc?

Hi, Phil -

I don’t think K3B lied to you; as I understand it, the gross amount of space on a dual layer DVD is 9.4 GB (4.7 GB for each layer), but the actual usable space is about 8.5 as a consequence of how the DVD drive laser and speed have to be adjusted in order to write to the DL-DVD. Here is a Wikipedia article on the subject: DVD+R DL - Wikipedia

Your DL drive and DVD are probably the most common DVD 9 (dual layer single sided, capacity 8.5 GB), rather than DVD 10 (double side single layer; each side is 4.7 GB, 9.4 GB for both sides together). DVD 10 functionally, then, is two 4.7 GB DVDs back to back, and cannot be recorded as a single entity in one session. This article has more information on the different kinds of DVDs available: DVD Capacities

This explanation is from the referenced Wikipedia article for how a DVD 9 recorder works:

"The stacked, shine-through arrangement of layers does come with a small increase in error rate due to reduced reflectivity of the written layers, and a similar small risk of crosstalk interference. One of the techniques employed to help compensate for these reliability shortcomings is a 10% increase in minimum mark (digital 0 or 1) length on the disc, with a corresponding 10% increase in rotation speed and 10% reduction in gross recordable capacity, accounting for the lower capacity of a single-sided dual-layer DVD at 8.5 billion bytes, versus a double-sized, single-layer DVD at 9.4 billion (for 12 cm discs). Detail differences in formatting and file structure mean the “usable” data area capacity does not change by exactly this much, but for all intents a DVD-R DL has effectively 20/11ths the capacity of a DVD-R SL, and the same holds for +R, commercially pressed, and 8 cm discs. "

Don’t be frustrated. It is just the way it happened when trying to squeeze double the data onto the same physical size DVD.