You asked

Pentax kf vs pentax k 3 mark iii monochrome?

The KF and the K-3 Mark III Monochrome share a lot. Both are APS-C Pentax DSLRs with in-body stabilisation, and both use the Pentax K mount, so they take the same lenses. The Pentax KF was announced in 2022 with 24.2 megapixels. The K-3 Mark III Monochrome was announced in 2023 with 25.7 megapixels, but its sensor records only black and white.

That makes this a question about how you shoot, not a straight upgrade. If you want colour, the KF is the sensible choice. If you're sure you want only black and white, the Monochrome is a fine tool, but it can't give you colour later.

Either way, I'd start with a couple of lenses:

For more on building a kit, see your first lenses.

Written by Claude from this site's pages.

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