Monitor setting: what's the best brightness level?

Look at something completely black. Like the RGB is 0,0,0

If it is a little grey your brightness is too far up.  

Every monitor is different so there is no 'pat answer' for this.
Set it where it's confortable.

If you are really concerened about health issues then get an LCD screen.
LCD's do not have an electron gun as do CRT's or TV sets.
There is no chance of any electron beam radiation leaking through the screen.
(Very unlikely with modern equipment anyway,, but,,, in theory,, you know...)

Refresh rate of the monitor has much more impact on comfort level than the brightness setting.  You should set the monitor to be above 60Hz freshrate in order to prevent flickering of the screeen, which can cause eye strain for some people.

You can "eyeball" the refresh rate by tilting your head to the right and looking at the monitor out of the corner of your eye.  If you see flickering, then you know you need to adjust the fresh rate.

You can adjust this by going to display properties > advanced > montior tab and selecting a setting from there.

Auriclus

Thanks for the replies, but I need to follow up on this, because when someone says to pick a setting that's comfortable for me, that's just my issue I'm trying to get addressed, they're *all* comfortable to me and I can't differentiate it, that's the reason I needed to know optimal settings from a health/comfort-level perspective, if such a thing exists.


* Auriclus, any "best" refresh rate? Again, they're all comfortable to me, so I cannot choose based on that. Just wanna know the practical setting that makes most sense, thanks alot.

* To everyone, true or false: totally ignoring personal preferences, the monitor brightness has absolutely NO IMPACT on anything, other than the user's choice on how bright they want their blacks to be?

lower contrast high brightness

contrast is what strains the eyes (depensding on the brightness)

If you are wondering about eye strain and health wise the only way is to get rid of your CRT and get an LCD monitor. CRTs scan each line on the monitor, then do a "blanked" retrace to scan the next line ( interlaced ) ( there is also non-interlaced)
Non interlaced scans evey other line then comes back and does the other lines, these types cause flicker. Anyway, you do not see the retrace, although your brain does, which causes eye strain. Also there is the supposed radiation with CRTs. Also I heard that while you are looking at a crt , also TVs your eyes are constantly focusing on the picture because the way the picture is painte on the screen. Also CRTs are bulky. I went from a monster 2 people to lift ( it was old ) 21 inch , that took up a lot of desk top to a 21 inch LCD.  WOW I got my desk back, then I saved more room. Most LCDs have bolt hole on the back and the base or stand can be removed. You can either buy or make your own wall mount. I made my own and my LCD is on the wall, zero desk top space...no eye strain, radiation ..etc.

adjust your crt so the picture looks good to you. Also position the monitor so that bright sun does not shine on the monitor for long periods of time. Degauss the display, most modern monitors have built in degaussing circuits that you can usually acces by pushing a button ot two on the front.  

I tend to go on the low side when it comes to brightness. This is very personal, but I find that it is less uncomfortable when I shift my eyes to something else than the monitor, if the brightness isn't set high. Also, a CRT will be more flickery at high brightness levels; a higher refresh rate may help there. For LCDs, the standard refresh rate is 60 Hz and they don't flicker anyway. I prefer LCDs anytime as I use the screen for reading/writing more than anything else. Someone doing much in the way of games ande graphics editing and such may have a totally different view on things. (screen type and brightness setting).
/RID

Thanks guys, this is really helpful, I'm going to leave this question open for 2 more days while I research this issue some, then come back and award the points.

refresh rate has no meaning when talking about LCDs. There is not flicker because there is no scanning or painting the picture on the screen. If you see flicker, you have a non interlaced crt.

here is something for you : self adjusting settings :

http://www.globalsources.com/gsol/I/17-18-inch/p/2000000003844/3000000171722/sm/1000929265.htm

for comfort wise there's a easy tweaking method.

Do this is a dark room.  Have the monitor set up to the brightess that your eyes can stand(usually 100%).  Slowly turn down the brighness.  At a certain point, you can feel your eyes relaxes from the brightness.  That's the sweet spot, just leave it at that.  With that brightness you can look at the monitor for hours on end, and it won't stress your eyes out too much.

However, I did find that if the room is bright, you might need to increase the brightness a bit, otherwise the screen is too dark, and you end up concentrating hard to make out what's on the screen.

Thanks guys, I'll try those two links out when I get home.