How do reds come out in your 5d3 ?

privatebydesign said:
But if nothing is capable of reproducing the "original" colours, which is true in very saturated flowers (not the camera or screen or printer ink), then all we can ever hope for is the best realistic interpretation and that has to include the detail, which we can accurately replicate if not the most saturated of the colours. If Perceptual is blocking up you have other issues.

Besides, colour is not as static a concept as we think, besides the "is red to me red to you?" unprovable conundrum, any reproduction is limited by what light is either shining on it, for a print, or out of it for a screen.

Best practice is to shoot with a color checker card and create your own profile, everything else is just guessing and we are notoriously unreliable at that, then post process for detail. It isn't difficult or time consuming, it just takes discipline.
You are quite right about colors being a matter of perception. Between reflective & transmissive mediums and individual vision, it's impossible to produce perfect accuracy. I feel that color management has come a very long way and gotten to the point where we can get close, but for me I follow the 80/20 rule. For most of my work, I use a calibrated wide gamut monitor and AdobeRGB color space and adjust to taste. That gets me close and really only represents what I believe the colors to be. For color-critical work (I shoot art reproductions and products occasionally), I build a profile with my Passport ColorChecker and shoot under controlled lighting and work hard to produce accurate colors. Even then, the final product generally depends on who my client uses for printing or their website (typically an ad agency). If they have me print, I generally use Bay Photo or Aspen Creek, and use their latest profiles. In the end, I've never had a print come out perfectly, but it's always been so close that no one (other than me) has ever noticed.

On a side note, the biggest shock to me when I started using a wide gamut monitor was white balance. In the past, subtle differences (of say 100K) had never bothered me, but suddenly I became very sensitive to them.