I use ColorEyes with a DTP94 puck to calibrate my Dell 3007HC to a luminance of 140 cd/m2, which I know is already on the high side for many who calibrate.. I use this site to make sure my gamma and gradients fall in normal ranges:
http://www.lagom.nl/lcd-test/, and for the most part they do.
However, I sense that my clients have their monitors set much brighter and in spite of all my careful efforts, my images, some of which can be on the tonally delicate side, appear weaker to them than to me. The other day it happened that a retoucher had his ACD setup next to my display and his was blazing compared to mine. I didn't think much of it at the time because in spite of the fact he hardware calibrates he was unaware of the term "luminance". However, he does work at an agency where he matches prints to GRACoL standards - so maybe something is just off in my system despite my best efforts.
I understand matching one's luminance to print viewing conditions, but what about for web work? How do I know I'm in the ballpark with the rest of the world? Or barring that, how do I have enough confidence that my system is right to tell my clients to match me?
And can anyone tell me the merits of ICC v2 vs v4 profiles, and LUT based vs Matrix?