Where does Lightroom display color space?

Question

Where does Lightroom display color space assigned to an image? It should be in the metadata panel. In Bridge it displays Color Mode: RGB/B&W and Color Space: sRGB/Gray Gamma 2.2. Or does Lightroom convert everything to Adobe RGB or ProPhoto RGB?

Answer 1

LR's internal working space is a variation of the ProPhoto RGB space, ProPhoto RGB's gamut but with a linear tone curve instead of the standard gamma 1.8 curve. This is because it is primarily a Raw editor and Raw sensor data is linear and because the ProPhoto gamut will more or less include all the colors most digital cameras can capture (depending on the filters in front of the lens, some cameras may capture ultra-red that is outside ProPhoto RGB). Retaining the linearity of the data makes editing calculations easier, faster, more flexible and more accurate since data has not been lost to the quantization errors involved in gamma correction. So for a Raw file the workflow is the assignation of the camera profile and conversion from that to linear ProPhoto RGB. However, the display data from the Develop module (the data sent to your monitor) undergoes a further conversion that involves the application of the sRGB tone curve, which is sort of gamma 2.2 but not exactly. This is because linear image data looks terrible - very dark and flat. Thus, the display is in a hybrid space called Melissa RGB, ProPhoto primaries and sRGB tonal response curve. At the time of export or printing a conversion is done from linear ProPhoto RGB to the output space designated by the user, which can be any RGB space - ProPhoto RGB, Adobe RGB, sRGB or any other one, provided you have an ICC profile for it in your OS's Color folder..
Previews used by the Library module are jpgs in the Adobe RGB space.