NX30, NX500, NX1

Yes, I'm using the Samsung 12-24. I picked it up in the early summer for a boat trip down the Rhine (castles and all) and the Greek islands, and have had an absolute blast with it - and the NX500. This is one of these lenses you put on and run with them, they just work so well. I really love it.

That it's slow doesn't matter for daytime photography. I also used it for sunset, after-sunset and indoor shots and it worked well for these, too, although for the latter two I should have probably slapped on the Samsung 16 f2.4 instead and saved a few ISOs. But the rendition of the 12-24 is very nice (I prefer it over the 16), and it's very sharp also wide open and without too much distortion in the corners at around 12 mm.

Moreover, I found that I much prefer a zoom for landscape and architecture because of the FL range, and for me 12-24 is perfect on APS-C. For portraits I like fixed FLs like the 30 and the 45, also as I can make more use of their speed. The Samsung will of course give you full functionality on NX, unlike the Rokinon, although it doesn't matter as much on a 12 mm UWA.

I suspect the Rokinon is cheaper, but the Samsung is really good. It also has very good flare resistance (unlike the Rokinon, I think).

Get a good polarizer for outdoor shots. It makes a big difference to any lens. I can recommend the B&W XS PRO MRC Nano KSM High Transmission (how about that catchy name) - it produces an amazing pop and crispiness. It costs just under 80 Euros for 58 mm. My only gripe is that it's tough to remove oily stains (e.g. finger prints) from it, and that it's sensitive to scratching. Here, the even more expensive Rodenstock (129 Euros for 58 mm) is significantly better, i.e. easier to clean and more scratch resistant, but the images with the B&W look better imo.

Andrea