Can a 45.7mp Nikon Z7 CMOS with IBIS and channel mixing hold up to a 18mp Leica Monochrom CCD for black and white? The design of the Bayer sensor removes resolving power while the non Bayer sensor with the same pixel count has up to 2 times more resolving power. Lenses are obviously an important consideration, but with Nikon's new 50mm 1.8S this might not be so obvious from prints. Hopefully, someone smarter than me or who has both cameras can shed some info on this.
I don’t have a mirrorless Nikon, but I compared my 18MP Monochrom and A7r2 pretty carefully and found no significant difference in IQ or resolution for 17x22” BW prints. Given similarity of sensors, my guess is this would hold for Z7.
An advantage of the color file is that in post-processing you can make use of color sliders to balance tones and contrast, as if you were switching through a whole set of filters on the MM. (This is what you’d use, instead of the old tools for channel mixing.)
For me, this control in PP was more important than any difference in resolution. So I got rid of MM and made a habit of using Leice MATE and WATE on a Sony body. (Because these are retrofocus lenses, they don’t smear the corners.)
Another problem with 18MP/original MM was lack of EVF. You can’t previsualize on the screen and have to accept some parallax and uncertain framing from the viewfinder. OK for street and snapshots, but clumsy for careful work on tripod.
Kirk
(BTW, re: other options for high-quality BW files: I’m now using GFX 50s with 32-64 zoom for BW conversions, and this is a definite step upa d in IQ beyond Monochrom or 42MP FF. The Fuji zoom is sharp but a little less ‘clinical’ than primes, and GFX sensor retains more highlight and shadow detail.)