T2I Users:
Anyone else have to do this yet? And if so how far? I already bumped it down one notch (from 4 to 3). I'm reluctant to bump it down another (2). The shots that there is enough ambient light, looked great... Thats why i'm afraid to turn the brightness of the LCD down any further.
I don't have the funds to invest in an external monitor. So right now this is the only fix.
any insight?

Steve

On your LCD brightness menu screen there is a "greyscale" to the right of whatever image you are looking at (usually the last still you shot). Be sure you can see every "step" from pure white to the pure black at the bottom of the greyscale.

This is where you really should be using an LCD viewfinder loupe as any exposure or LCD brightness "judgement" you make should only be done with all extraneous illumination blocked out. I use the Hoodman Hoodloupe with 3x eyepiece. I actually have 2, one is mounted on the Hoodcrane and the other I just bought from a friend who didn't want to keep it. That one stays in the bag with a lanyard/neckstrap for when I just need something to hold on the LCD temporarily.

Typically I need to increase brightness out in bright sunlight (my eyes adjust to the high bright level and even with the loupe I need to increase LCD brightness. And at night I find I have to decrease LCD brightness (again my eyes have adjusted to the night environment). As long as I can distinguish all steps on the greyscale I'm OK.