Banded sky when printing?

[Xarra]

I'm printing some pictures on a laser jet (HP4600) to test quality, and on some of the pictures where the sky is very subtly shaded (OOF clouds on pale blue sky...) they're printing in kind of bands of colour...

I'm wondering if this is a limitation of the printer and a photobook printer will be able to cope, or if I need to try and sort the sky out somehow? (Ideas welcome if so!)

BTW: Pictures all 300DPI 10x8 sRGB. Printer claims a 600DPI res...

Attached is an example of the printout (excuse the biscuit crumbs...) and the original picture is here:

http://www.flickr.com/photos/clareselley/3555362374/

[Stewcp]

Are you using the correct profile for the paper and printer?

[Bandit]

An 8 bit jpg may do this, try printing from a 16 bit Tiff with an Adobe98 profile.

[chaz]

To me it looks like the histogram has been stretched using either, levels, curves,brightness/contrast, etc and produced posterisation, this happens when expanding the tonal graduations in 8 bit, the limited bit depth cannot give a smooth tonal graduation when tweaking to the extreme, does the histgram look all spiky.

[Xarra]

Chaz - It looks fine on the screen though...

It needs to be in sRGB JPG for the Blurb software...

I'm going to do a test print at a photoshop tomorrow...