Instructions and cautions cleaning inside a Toshiba 50H13 I live in Arizona and dust gets everywhere. I think the DLP mirrors and inside the screen are dusty.

The old ballast can be repaired if you know which component is bad. You can get parts from here:
TV Parts Universal TV Stands DLP Chips ShopJimmy . They have a repair service as well. Unless there is something on the mirror that is showing up on the picture, cleaning the mirror is tricky. You should use a glass cleaner that has NO ammonia in it and NEVER use paper on the mirror to clean it. It will permanently scratch the surface which you will see in the picture forever. If you must clean it use a lint free cloth like microfiber and never rub in circles or press too hard.

Two things to look at from rear with back off: one is the inside of the screen and or the large mirror in rear of unit--do not touch mirror.

second is the unit has a small lens (2-3 inches) the points up towards the mirror---dust or such on it will cause this--it can be cleaned with a lens cloth.

If the mirror has this (uncommon) the entire front of set would have to be removed (screen units) and that is not real easy.

If lens and mirror and screen are ok problem is INSIDE the optical unit that the lens is part of---on rare occasions that can be cleaned out with compressed air.

without seeing a photo of what it looks like this is all I can suggest.

I think you have one of the models that have two mirrors inside: not Mitsubishi's best idea.

Most have just the large mirror in the back but I think this model has a very small mirror at the bottom (odd shape about 4x6 inches) behind the front screen which faces upwards and gets dirty from the fans inside the set.

It is amazing how much it can dim the picture; Caution, if yours has it the only way to get at it is to remove the entire front screen assembly---a phone call to Mitsubishi will confirm if your model has the two mirrors----the big one never needs cleaning(almost never and is special).

If you find your model has two mirrors either consider having a pro come out and do it (15 min job) or You Tube it to see if instructions there.

look before you leap as this is usually a two person job.

If you have questions let me know.

I have seen this before in these sets

SD TECH

I think you have one of the models that have two mirrors inside: not Mitsubishi's best idea.

Most have just the large mirror in the back but I think this model has a very small mirror at the bottom (odd shape about 4x6 inches) behind the front screen which faces upwards and gets dirty from the fans inside the set.

It is amazing how much it can dim the picture; Caution, if yours has it the only way to get at it is to remove the entire front screen assembly---a phone call to Mitsubishi will confirm if your model has the two mirrors----the big one never needs cleaning(almost never and is special).

If you find your model has two mirrors either consider having a pro come out and do it (15 min job) or You Tube it to see if instructions there.

look before you leap as this is usually a two person job.

If you have questions let me know.

I have seen this before in these sets

SD TECH

You will need to remove the back cover. Here you will dust the lens with a pressure can of air only. Then you proceed to clean the lens with an eye glass damp cloth Get these from an eye doc). As for the mirror, you must use real caution. This mirror is made of a stretched plastic. The best way to clean this is to use a new feather duster. Do not even think of using anything wet to clean this mirror. It is very fragile. Let me add, that you want to do this from the rear also. Next, I would not recommend you try to pull the front cover (screen) off. It would be next to impossible to put the screen back on the TV. You will also feather dust the inside of the screen from the rear. No wetting solution here. Be sure your TV is not plugged in. Thanks for asking and show all hands of support!

Check for dust on the lens. There may also be dust inside the projector on the mirrors, lenses, or LCD. If cleaning the lens on the outside doesn't resolve your problem, I would contact a professional to get the insides cleaned out.

Good Luck!

Did you ever get this addressed?

there are screws behind the speaker cover-remove them-take out screws along back edges-carefully remove screen(its plexiglass) clean all 3 tubes with a soft cloth -be carefull cleaning screen most liquids will stain it-also clean mirror-reassembly unit

Most likely cause of your trouble is dust on the small mirror inside you set. Your DLP set has 2 mirrors not including the DLP chip itself which has about 500,000 tiny mirrors. The 2 mirrors reflect the DLP chip image to the screen you view. The first is the main suspect it's about 4inches by 7inches. It's mounted on the bottom center facing backwards. This mirror faces slightly up and somtimes after time dust, smoke, dirt settles on it . The second fills the space of the entire back of the cabinet but it faces down and takes alot longer to get dirty.
The compartment is sealed but dust seems to find it's way in. If you remove the screws that secure the screen assembly from the top , sides and bottom. Make sure to have a friend available the screen assembly is delicate when it's not mounted to the cabinet. You can remove and clean the mirrors. These mirrors are glass and you can use glass cleaned. Don't use glass cleaner on the screen it's plastic. You can clean it if necessary with plastic cleaner only. Probably not needed.
Good luck.

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