Spookily enough, Crackle, when I was researching cameras a while back, reading reviews, watching YouTube videos, I'd decided that a Pentax K30 would be the DSLR I'd buy, were I buying one. The fact I've got the Nikon on loan means I can avoid such a decision for now :-)
I found Doseone's comment above ("The g3 deals with the highlights better but the colours are punchier on the Pentax.") very useful. I wouldn't have picked that stuff up myself. But once I read it, I could see it.
Anyway, I had a go at a couple of comparison shots. Top one is G3, bottom one is 5100. Lens on the Panasonic was the 20mm, and on the Nikon it was the 18-55 (at 22m). ISO on both was 160, aperture 7.1 at 1/200th.
Converted both to JPEG and reduced the size so the files weren't so big. When working side by side I must admit the viewfinder is way nicer on the Nikon - but I still like the quick review you get in the EVF on the G3. It's very annoying that the little scale to show whether you're under or over exposed is the opposite way round on the Nikon to the Panasonic (or vice versa). And I found it easier to get to things like ISO and White Colour Balance on the G3. But all of these are minor things. It would be nice to keep both...One for when I need to travel light. And one for, well, other times. That said, not sure I can see much difference here:
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