Above image of an Orchid on my kitchen windowsill was taken in natural light with my Nikon D200, focal length 35 mm, aperture f/4,5, exposure time 1/80.
For online text I use the HTML value B163A3.
Here's how you can find it in your colour systems.
RGB: R 177, G 99, B 163
CMYK: cyan 33 %, magenta 72 %, yellow 0 %, black: 0 %
And finally Pantone: PMS 18-3224
Don't get it mixed up with Radio Orchid ;0)