I used Photomatix and on a few images there is a purple cast; what caused this and what can I do to prevent it?

Attachment #1, (jpg file)

I think it has something to do with certain lenses in dark areas of the picture. I have a 14mm prime lens that does that to me once in awhile. I can take the same shot with the 17-35 at 17mm and not get the purple cast. If you can, try the same shot with a different aperture and make sure there is no dirt spots on the lens.
Larry
http://www.larryandersonphotography.com

All right; I guess there is no way to predict so this is just something that happens.

Bob

Is the purple cast in each image before processing in Photomatix?

Check the version of Photomatix you're using and against their site to see that you have the latest (3.2.0). I noticed significant improvements in image handling lately.

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Oh, and another thing...

If you processed the raw NEFs with Photomatix, you might also try the following experiment. Bring the NEFs into a specific color space using a raw processor like NX2 or LR, export TIFFs and use those in Photomatix.

This adds a step, but my observation has been that Photomatix is less prone to adding artifacts when it's dealing with images that already have a tone-curve applied via an embedded color profile.

I personally prefer NX2, since I can apply Picture Control settings and use arbitrary color spaces with it; but if you have LR, then use ProPhotoRGB for a big space.

Visit my Nikonians gallery.

Visit my Nikonians gallery.

Yes it is!

I didn't notice before; the original image is darker and it didn't show up as much.

So, is this a lens problem?

Bob

The purple cast is not a result of HDR. I looked at other images and it shows up a many of them.

So, I'm moving my question to a lens forum.

bob