Orange-Green specularity?

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It looks like that because HPL uses combined gloss and specularity maps. So the red channel of the image is used for specular and the green channel is used for gloss. (Or the other way 'round - you can find it in the Wiki) I'm not exactly sure why, but I guess it improves performance. In order to create such a map you simply copy your (black and white) specular and gloss maps into the respective channels of a new file. Its pretty easy to do in Photoshop.