OK, here is an example of converting Andrew's photo from ProPhoto to sRGB using both a Perceptual mapping and a Relative Colorimetric mapping. If you don't believe that it is possible to do a Perceptual mapping from Workspace to Workspace then look here:
http://www.luminous-landscape.com/forum/index.php?topic=93997.0, where I explain two methods of doing so (the second method is certainly the one I would prefer at this stage as the first method relies on a beta v4 profile from the ICC).
![](http://www.IrelandUpClose.com/customer/LL/pp-srgb-comp.jpg)
[Right-click on the image to see it full-size]
The left-most image is Andrew's original ProPhoto image: so what you see will depend on your display, but even with an AdobeRGB-size display the colors are being mapped with a Relative Colorimetric intent, so some of the colors will be clipped and shifted.
The middle image is converted from the original ProPhoto image to sRGB using a Perceptual mapping and the rightmost image is converted to sRGB using the normal Relative Colorimetric mapping.
I have indicated areas that I think are better in one image compared to the other. In general I would say that for this particular mapping from an extremely wide image gamut to sRGB that the Perceptual mapping works best, but there are areas where the Relative mapping seems better to me. At any rate, I am not advocating one mapping over another: but I am suggesting that having the ability to choose the rendering intent, especially when converting to sRGB (for the web) is a really big advantage.
Of course, needless to say (if you have read my previous posts here), I think that converting this image to sRGB is doing it a serious injustice as the image gamut is way outside any output device or display profile that is currently available.
Robert