My small IR kit, using a lens focal length factor of approx. 2X. I have given priorities whenever possible to smaller and lighter lenses, however as focal lengths grow that becomes rather difficult.
From left to right, middle row: Laowa 11mm f/4.5 (using rear-mounted gel filter), Viltrox 20mm f/2.8, Nikkor Z 40mm f/2 SE, Nikkor 85mm f/2 AI, Voigtländer APO-Lanthar 180mm f/4. All lenses except the Laowa are CPU-enabled. The niceness of this kit is that most can take 52mm filters (20-180mm optics).
Rear row: Nikkor Z 400mm f/4.5, very lightweight for its focal length, however cannot use internal filter so requires expensive 95mm filter size.
Front row: GPS recorder Transystem GL-770M, Nikon Z5 (full-spectrum modified) with extra power pack and Foolography 18'N2 GPS module, FTZ adapter for the F-mount lenses.
All lenses are good to excellent in IR, however the 400mm should not be stopped down all the way unless you specifically wish to have an IR hot spot
I tend to use it in the f/4.5-f/5.6 range where it performs excellently for IR. The old Nikkor 400mm f/3.5 ED-IF can use internal filters (39mm) and is maybe a tad better for IR, but is much heavier and of course manual focus only. The Zoom-Nikkor 80-200mm f/4 AiS can substitute for the 85 & 180 lenses for some assignments. If I plan on shooting close-ups, I might bring either the Micro-Nikkor 105mm f/4 or UV-Nikkor 105mm f/4.5 instead of the 85mm. If I have any urge to lift weights, the wonderful AFS 200mm f/2 Nikkor can replace the CV 180.
