@GlennMarlowe I don't have an UV filter with me, it might well be the culprit here. Here's a shot with my #IR630 filter, colors not swapped, color temp 3600K, tint 1.711 (this slider works differently in #darktable). It seems to come a bit closer to your colors, and I could probably turn up the contrast some more.

So spring has finally arrived, and so have my 72mm #infrared filters! 😻

First image is #IR950 sepia, second is #IR630 red-blue swapped.

📷 #SamsungNX NX500 16-50mm S lens