K5 / Apple Aperture Flash White Balance Inconsistency

Used my new K5 with studio flash for the first time on Saturday. I got some peculiar colour temperature results. Can anyone explain this?

All shots used the following settings:
- Raw DNG
- Adobe RGB
- Camera white balance set to "Flash"
- ISO 100
- 1/180s
- f/11 to f/19
- same lens used throughout ( Pentax A 50mm macro f2.8 )

When I loaded the raw files in to Apple Aperture the colour temperatures of the raw conversions came out as an inconsistent variety of temperatures and tints. As sample, the first ten shots on the "roll" show the following white balance values after raw conversion (prior to any manual adjustments being made):
5759 K / +4
5759 K / +4
5759 K / +4
5759 K / +4
4492 K / -9
4479 K / -7
4463 K/ -8
4469 K / -11
4563 K / -8
4572 K / -8

(For what its worth, 5759 K / +4 looks right to me.)

What is going on? Do I have a camera or a raw conversion problem?

Please only post a question once in one forum - if it turns out it's in the wrong place we can always move it for you.

I've removed the other thread.

That seems to be the answer to my question - I've looked at my camera and the "WB Adjustable Range" was set to ""Auto Adjustment". I didn't know about that setting, (it must have been off by default on my old GX20).

(The range of colour temperatures that I got in those ten photographs, from 4563 K to 5759 K seems to me rather more than a "small margin". During those ten photographs, the camera remained in the same position on a tripod, as did the studio lighting. All that changed between frames were small adjustments to strobe output. That might, I suppose, produce a slightly different colour illumination. However, if it did, then the K-5's "Auto Adjustment" feature was failing to compensate correctly, as there is little consistency in the colour on screen of those ten converted RAW files. I think I'll be keeping "Auto Adjustment" firmly "Off" from now on.)

Thank you Matt & John

here is the fix (works for me) I use a grey card.
I set the white balance in aperture off the grey card then lift and stamp the adjustment to all the images in the set.

in your case you could choose the best white balance off one image and stamp it onto the rest in the set.