Linux Nvidia geforce 630M
2.8 "Date: 2018-06-01"
Short description of error
The value of 'V:' (value) always gives the same value as 'L:' (luminance)
I think it's different data, you should see different values.
In Natron there are different values between 'V:' and 'L:'
This occurs in both blender 2.79b and 2.8 builds.
Exact steps for others to reproduce the error
Open one image, or make a render, and click with ctrl + left click in the image
Diference between value and luminance: video