Author here. Great point about the lens-dependent abberation, I mentioned this briefly in my earlier write-up about doing the full spectrum mod [1] but forgot to mention it by name here. I've been trying to get by without spending a lot of money on lenses and have gotten a lot of mileage out of a cheap used 50mm lens that _feels_ like it's just one or two solid glass elements. Fortunately the old camera mount I'm using means all the lenses for it are used, old, and super cheap secondhand. I'm about to try my luck with a 300mm lens. IR should be fun but we'll see if I can squeeze any UV at all through that.
Beautiful shots you have with your own full spectrum camera. Originally I somewhat dismissed the Kolari IR Chrome filter because the suggested combination with a channel swap and custom LUT felt a little too heavily edited for me and I prefer to stay close to the dry camera signal. The shot with the Tiffen Deep Yellow filter is gorgeous, how does that one look on the camera LCD without the channel swap?
[1] https://timstr.website/blog/diyfullspectrummod.html