How do you do it?

[AndreaB]

How do you produce a high key image?

[James T]

In camera. Not in post processing.

Light / set-up the shot so that it contains a majority of tones above mid-grey. Job done.

[ricktas]

Agree with James, do as much as you can in camera, then you can tweak it in PP, but trying to turn a shot into high key that did not start out that way, generally doesn't work.

Learn how to use curves adjustment layers for the PP part

[aycee]

To get high key images i think the easiest way is to use AEB on all you photos if possible and take them a bit darker to start with and then by combinations of both erasing, gradients and layers to get the contrasts where you want them before any filtering at all as any filter does test the pixels...use RAW if possible as that has more info in it and can be played with without loss and use 16 bit if your computer can stand enormous file sizes..hope this helps but i arent any expert in all this though i do think if you take photos on the premise of what you can do in PP it is much easier now that the technology is available but you cant make a silk purse out of a sows ear..Alan!