Mitsubishi 3780D picture is way too dark

Try going with just a shade brighter and redying it. All colorants seem to brighten as they set in. I'd say you can do that, or try getting your hair more sunlight. That will naturally brighten the color.

Provide with the TV model number.
It could be a lamp burning out.

Assuming brightness and contrast (picture on some sets) does not help it could be a number of things, how old is this set?

adjust the color go to the menu and change the color meter to darker or lighter and your welcome

how about in the menu button you can not get an adjustment in brightness control. if the display in the screen is too dark either in any channel or even watching a movie from an input source like dvd player, then i may say that the picture tube need now replacement.

Changing the contrast will also help brighten your screen. For best results, try changing the contrast and the brightness, to find the perfect combination for your needs.

If the pictures of a TV appear to be darker than they are used to be the first thing which should be checked are the brightness and contrast button. Check for them and increse either one or both of them to brighten your picture.
Hope this solution has been helpfulo?

seems like its the inverter thats either not working or the tubes are faulty

no those tvs came with a black otuer screen that have rough ridges . If your screen is blue, someone may have replaced it with a dark colored plastic. You can get replacement screens at the following link, They are exspensive though.
http://servicemanuals.vstore.ca/

Try hooking the TV to a different outlet fed by a different breaker. Does the problem go away? If so, the culprit may be a wiring problem in your house that is causing the TV not to get enough power unless the dining room light is on.If in doubt, consult an electrician to make sure both the dining room light and TV outlet circuits are working properly.