For the sake of your data, I won’t do it, but I absolutely could embed this image into a comment, and if you don’t have much data, you could get screwed: https://www.eso.org/public/archives/images/large/eso1719a.jpg

It’s a 1.3GB image of 3 nebulae. Its resolution is 93031x35412 which makes it nearly 3.3Gpix. Yes, that’s gigapixels.
Source: https://www.eso.org/public/images/eso1719a/
The original is 9.2GB.

There’s also this 8.8Gpix 24.6GB Milky Way mosaic, but that’s not available as JPEG in full-res: https://www.eso.org/public/images/eso1242a/

That’s 0 kB wasted.