Purple fringing on DA 16-45mm?

While testing (and learning) my new K20D I took a picture of a tree. The picture has been taken with DA 16-45mm and I'm a bit surprised - all the branches are surrounded by a purple fringing :. Actually I never paid too much attention to that before, but this time it was really visible and I expected a bit better results. Is it me doing something wrong or is it normal or I should postprocess it?

This is the full image (scaled down):
[IMG]http://i384.photobucket.com/albums/oo284/misiek_knm/imgp0126scaled.jpg[/IMG]

And this is a full crop of a top-right part:
[IMG]http://i384.photobucket.com/albums/oo284/misiek_knm/imgp0126crop.jpg[/IMG]

What do you think?

Michal,
There will always be situations where you get such purple fringing, unfortunately
If it bothers you then you can post-process to remove the PF. There are some free Photoshop PF removal actions around. My suggestion (especially in this instance) is:
* Create a new layer in PS
* Change the layer mode from "Normal" to "Color"
* Get a small paintbrush, at 50% opacity
* Alt-click on the blue sky or branch
* Paint on the purple

You could use the select color range to pick up the purple automatically.
HTH!
Matt

Thanks, Matt. Normally it doesn't bother me much, but I just wondered what can I improve and how can I prevent it.

I don't use PS, but I believe it will be quite similar in GIMP, so thanks for the tip. I'm a completely 'newbie' in the postprocessing yet

It is one of the "weaknesses" of some Pentax glass & I've read comments in reviews of the 16-45 to this effect. It's probably not going to show up too often and most times you should be able to remove it with PP

... on a positive note the Pentax 16-45 isn't anywhere near as bad as the Tamron 70-300 I used to own, had to get rid of the lens it was so bad

Simon

I use something that looks like Matt technique.
* Create a new layer in PS
* Change the brush mode from "Normal" to "Color"
* Get a small paintbrush, at 100% opacity
* Alt-click on the blue sky or branch
* Paint on the purple
* Change the layer mode from "Normal" to "darken"
* Adjust the opacity of the layer if needed

I haven't tried Matt's one so don't know which one is better

I have found that the "Lens Aberration Controller" in Silkypix allso does an excellent job in removing CA if it exists.
The Photoshop method will probably be a little more accurate but the Silkypix method is very quick.

I will have a go at the mentioned Photoshop methods as well.