QTR-Quadtone RIP

> 
> That sounds like a strange advice to me. QTR uses a grayscale image. Any toning is done by blending curves, as the OP seems to do correctly. Having said that, I've no clue why it doesn't work in his case. Espeoially since it happens with the first curve being at 100%.... Puzzling indeed....
> 
> Joost

Yes, struck me from the instructions that the curves were applied in order to tweak a neutral image - otherwise how would the split toning offer work?

However, is it standard practise to use a grayscale image or a de-saturated RGB image? (I notice there are two options to choose from in profiles).