Travel with NX10
yes if the green light is flashing, that means its copying the image to the card.
If its flashing, you can only compose, but not go into any menu nor change any setting. If you take 3 raws in a row, the buffer time will be noticeable. Jpeg, if you can live with the quality, of course is faster since you won't hit the buffer so fast. If you have High-ISO and long shutter noise reduction on, the screen will go black as it processes the image. If you do 3 bracketed shots at long shutter speed, you basically have shutter speed, the processing speed (same as the shutter speed), and the transfer to the card. If you have a nx200 you can use a UHS-1 card and speed up the write times, but also what I do is shoot raw only when I do brackets, and extract the full jpeg that is embedded in the SRW file. This saves 15+ megs of jpegs per set of 3 bracket sets. While the performance can be maddening, it is no worse than a raw shooting compact like the TL500, lx-5, or s100 and actually better considering you are shooting 15 megapixel images.