For instructional purposes I exported four Raw files as DNGs, with Lossy Compression, and reduced the size from the original 7360 pixels wide by 4912 high to 2000 pixels wide by 1335 high. When I used these reduced-size DNGs to create a panorama with the new Panorama Merge in Lightroom CC, the merged file was 16813 pixels wide by 4987 pixels high. What? Apparently it's basing the size of the panorama on the size of the original Raw files, not the reduced size. Why would it do that? And how do I make it stop? Since it apparently up-resed the DNGs, the image is very fuzzy when I zoom in, and unnecessarily large. I tried this with the HDR Merge too, and the same thing happened - it created an HDR file that was the size of the original Raw files, not the reduced-size DNGs used to actually create the HDR merge.
What version of LR are you using, precisely?
I'm using Lightroom CC 2015.1 on a Macbook Pro running 10.9.5.