MountainDog wrote:
The thing is that I can open the raw file in Canon DPP 4 and there is absolutely no magenta highlights when I decrease the exposure. So this is a Lightroom problem.
There is a large area in the IMG_1672.CR2 that is badly clipped in the Blue and Green channels when viewed in RawDigger. There's no way you can determine this from inside LR!
MountainDog wrote:
I haven't tried it yet, but a possible solution for HDR would be to export the images from DPP as 16 bit TIFF, merge them with Photoshop and work with the 32bit TIFF in Lightroom. Has anyone tried that yet?
DPP is incapable of recovering the same highlight detail as LR5. It may not be pink, but there is no recovered image detail using DPP with your IMG_1672.CR2 file. As Bob suggested you can get fairly decent rendering with this image inside LR5, even though it is clipped in two channels in some areas. Please read my post #25 here for a possible solution when processing HDR bracketed image files.