Again the M5 has a touch screen and so did my D500 but that is turned on and off with liveview on the rear screen, you simply don't need a sensor to do that, especially on a DSLR.

The only thing that makes me wonder is the small sensor below the viewfinder. People have said its to turn off the back screen if you bring the camera up to your eye but to me that just screams overkill when you could do it with a simple button press which you are going to do to turn liveview on to begin with.

My little Canon M5 has the same sensor next to the viewfinder and that is to turn the EVF on when the camera is in power saver mode and you don't need that for an OVF.

Anyway, I would be up for such a thing but I think it's unlikely this time around ... I think the 2/3 years of development time for the prism viewfinder is just Pentax/Ricoh working at their own snail like pace.

Must say when I had my APS-C body my most used lens was the 20-40mm f/2.8-4

Excellent piece of glass I thought, every bit as good as the LTD's

Another vote for the first one ... superb.

Have had both multiple times, ended up keeping the Pentax.

Sigma has fast af, HSM is better than SDM and it's sharp at f/2.8. Pentax has slow AF, SDM isn't as good as HSM, it's WR and it's very very sharp at f/2.8. It also renders much better than the Sigma.

Not sure it's me but on every Sigma I have had (not just the 50-150mm) you can set up the focusing on the Pentax body and it will be absolutely spot on. Go to use it the next day and it's slightly out. Really Really annoying.

Mmmm, always wanted to try the NX-1.

Welcome (once again perhaps) ?

Very nice indeed, not got any dragonfly pics this year ... mind you, not really been anywhere this year.

I It's a very decent lens isn't it. I got mine out a few days ago and the results are excellent but then it went back to the shelf. Just don't use primes.

I always think people must be moving brands when I see a 150-450mm for sale as it's genuinely the last lens I would ever sell.

Therefore if you see mine up for sale soon you know I am buying a Canon R5

The lens firmware has to be updated by Sigma as it is an old version. Only the newest Sigma lenses can be updated by the user with a dock.