MY 2004 Sony rear projection 57 inch tv doesn't show very clear. It is bright and will not darken enough.

Hi, I used to work in Best Buy and one of the key things about rear projection TVs and the reason they push those service plans on you is that the tubes/colors need to be calibrated each year. You can do this yourself by checking out the following website:  

http://lgknowledgebase.com/kb/index.php?View=entry&EntryID=3229 

If you are not able to adjust the convergence using the remote you will need to replace the convergence chips. 

Typical Symptoms

1) Convergence menu does not work for one or more colors.  
Such as: Red moves up,down, but left or right fails. 

2) Screen is bowed looking.

If you have one or more of the problems above you need to replace the convergence chips. You can get a kit and instructions from www.TvRepairKits.com  

Hope this helps :)