Get it here: http://dcptool.sourceforge.net/
What I've done, in response to requests from folks on the Adobe forum, is to add the capability to modify DNG Camera Profiles to either change, or entirely remove the "hue twists" that I described in a previous post.
The previous modifications that I had made to the profiles was simply to move the "LookTable" to the "HueSatDelta" table - this means that any hue twists are processed before the exposure controls, so the problem that changing the exposure control changes colors goes away. However, some further tests have made it clear that profiles don't always respond well to simply being moved from point to point in the processing pipeline. So, in addition to the ability to change the processing pipeline order, I've also added the ability to effectively freeze, or "untwist" a profile - so the processing pipeline remains the same, but there is no change in tint when you adjust exposure.
This "untwisting" is my recomendation as to how to go forward if hue twists are giving you a problem; in my tests so far, color reproduction is very similar to the original profile, but the color shift problem is entirely eliminated.
There's more detail on exactly what dcpTool does to untwist profiles here.
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