As an update, I managed to get 3 out of 4 sheets from last weekend! Here's one:

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I bracketed the shots at ISO 6 and 12, though I should have gone 3 and 6 or even lower perhaps. The negatives lack some shadow detail but the highlights seem about right. I developed them in XTOL Replenished for 10 minutes at 20C in a DIY rotary at 30 RPM. I use a JOBO 2500 tank with the 4x5 reel. I was worried that the sheets might move around but it seemed ok.

To prevent fogging during exposure, I used a foil mylar sheet that's for plant beds and wrapped that around the bellows and used my dark cloth for the back. I think I should have also considered wrapping the mylar it around the back as well as the one exposure that didn't turn out was fogged but on the bottom side of the holder and I can't quite work out how. I think it was when my dark cloth flew off (it was windy when I was trying to make that exposure).

These are not the best representation of IR since they don't have as pronounced an IR effect. I used an R72 but the time I took these may not have been ideal and I might want to also couple it with a circular polarizer perhaps?

Anyways, in short, I finally managed for the first time to get IR results with the film in large format, so I'm pretty happy with that!