get ur hands on a copy of animagic, and read the help file, save as a compressed gif, it will be smaller than jpeg

or

use a brightness algorithm, and apply to constantly(will draw slow)

brighten

Red = Red - (txtBrightness.Text * Red)
Green = Green - (txtBrightness.Text * Green)
Blue = Blue - (txtBrightness.Text * Blue)

darken

Red = Red + (txtBrightness.Text * (255 - Red))
Green = Green + (txtBrightness.Text * (255 - Green))
Blue = Blue + (txtBrightness.Text * (255 - Blue))

actually i think i got those mixed up try them both. im assuming that u can use getpixel/setpixel. Red,Green,Blue are bytes to which u fed the color. This is slower than my internet connection(which is saying something). txtBrightness is a textbox containg a percent(in decimal form)

...and corned bee, the big give away that ur in the wrong forum, see at the top where it says Visual Basic > Games and Graphics programming...