AF system on NX + few other questions about the NX system

Hi all,

I used to own several Pentax DSLR bodies (K10, K20, K5) and switched to FF a year ago (D800).

Although I'm beyond satisfied in term of image quality, I'm slowly getting more and more tired of AF accuracy issues inherent to the PDAF technology. Additionally, I've been more and more fed up with the volume and weight of FF gear.  Back to AF, it makes sense that the higher resolution the sensor, the more visible any potential inaccuracy will be.  I'm not a sport shooter, so I can't care less about focusing tracking.  I want spot-on accurate AF and from a technological point of view, CDAF is the way to go.  It works on the final image, therefore no body + lens calibration is required. It just works (or so it should, at least in theory).

I'm attracted to the NX system for 3 main reasons:

1. APS-C sensor size: I really the flexibility of a FF sensor as it can do everything a smaller sensor can do, plus more (DOF control + high ISO advantage). The MFT system is great, but in terms of DOF I find it too limiting, plus lens prices are pretty high. I think APS-C sensors are the sweet spot between size and IQ flexibility.

2. NX lenses: although there are not many lenses, they are of high quality, cover my need (except at the long end perhaps) and are well thought in terms of the whole system.  Only Samsung seems to understand the value of making small pancake primes that are good optically while being reasonably priced.  The focal ranges of NX primes makes a lot of sense (except perhaps the 45 and 85mm? Why not a 55mm for portrait instead?). This is where NEX sucks big time: lens selection; they don't seem to understand people want small lenses to go with their small bodies.

3. Price: all NX primes are very reasonably priced compared to what you would find in MFT or NEX.   Plus I like the fact they are quite fast while being very small (not all of them obviously, but the ones I'm mostly interested in: 16 and 30). The

As I've never had the opportunity to try the NX system, I have a few questions:

1. How reliable is the AF system?  I assume it would be spot on all the time (providing it's not used in complete darkness), but is it always the case? I don't care too much about the speed, but is it fast enough for practical use? (I'm not talking about tracking which I don't care for).  MFT is great at focusing and would like to know how NX compares.

2. I almost always shoot in A priority. How does auto ISO work in A mode? Can I set the maximum ISO the camera will use? Does it adjust the ISO in a sensible way, ie. according the focal length for instance?  The Pentax implementation is brilliant IMO. I hope Samsung does something similar. I rules out NEX just because of this: auto ISO caps at 1600 and 1/60 sec. regardless of the focal length.  Total utter non-sense, as the designers  never used a camera before.

3. Slow RAW buffer writes: is it still a problem with the latest bodies and firmware? (NX 20, NX 210).

Thank you a lot for your help.

--
Florent
http://capturedbyflo.com
http://capturedbyflo.blogspot.com