Bart, so no on the contrast progression demo.
For the moment Tim, but don't despair
I may yet solve the issue, and show something side by side, maybe even a video.
Too bad. I would've liked to see just how well C1 Pro applies it because that Topaz video gave undesirable results. I can't use C1 Pro because I don't have a current OS that supports it.
When I get a bit more time, or solve the issue with some CGI test images, I'll put something together that allows to compare with ACR/LR.
Cheers,
Bart
P.S. It's a pity that ACR/LR doesn't offer an option, like in Photoshop (luminosty blending) but I understand that PS uses a different (non-parametric but layer based) processing workflow.
An application like Photoline offers even better tool options than Photoshop. It allows to choose the colorspace in the Curves tool (see attached), as it will be applied to a layer, or it allows to add it as a separate adjustment layer.