# Focusing screen help needed!



## itsbudda (Jul 7, 2010)

So I had some bad smudges all over the focusing screen of my Pentax LX.  My teacher suggested I clean it with a little alcohol and a q tip.  I got the smudges off perfectly but now the screen is completely covered with streaks!  I've tried water, more alcohol, and a citrus cleaner, all to no avail.  I've tried soaking the screen and still nothing.  As soon as it dries different streaks appear.  I can barely see through the viewfinder.  Is it possible to make it clear again or should I just get another screen?


----------



## compur (Jul 7, 2010)

Unfortunately this often happens when solvents are used to clean these small
focusing screens. I don't know of a solution that works reliably.  My personal 
method from past experience is to use only dry air or dry swabs or brushes to 
clean a 35mm screen. No liquids of any kind.

Maybe someone here knows a remedy but I think you'll probably have to get
another screen.


----------



## Josh66 (Jul 7, 2010)

What is it made out of?  Glass?


----------



## itsbudda (Jul 7, 2010)

I think it's ground glass with a matte finish.  I'm likely wrong though.  I was pretty sure it was toast as soon as rinsing it didn't work.  Luckily I just found a buy it now on ebay and have the cash handy.


----------



## Dwig (Jul 7, 2010)

itsbudda said:


> I think it's ground glass with a matte finish. ...



Its almost certainly plastic. Focusing screens are extremely fragile. Many can't be cleaned by any mechanical means (tissue, Q-tip, ...) without doing permanent damage.


----------



## Mike_E (Jul 7, 2010)

Can you take it out and wash it with soap and water?  Just be sure to put it back in the same way it came out.

Hey, if it's ruined anyway..

It's also possible to grind your own if you have to, you'd just need to find the proper thickness  and cut it (have it cut) to the right dimensions.  

That or buy a parts camera from e-bay and change out the screen from it.


----------



## compur (Jul 8, 2010)

I believe the LX and MX screens are interchangeable if that's of any help.

An LX screen by itself may be pricey but a junker MX with a good screen
would probably sell for only a few bucks.


----------



## itsbudda (Jul 8, 2010)

I knew they were interchangable but the thought never occured to me to just buy a parts camera.  Too late now but if I ever come across a broken MX I'll probably buy it for that reason.


----------



## itsbudda (Jul 8, 2010)

Well then this can serve as a cautionary tale.  Don't do this unless you want to look through that


----------



## Paul Ron (Jul 8, 2010)

Cheesie wheeezie, did you use a blow torch to clean it?


----------



## dxqcanada (Jul 8, 2010)

If the matte side of the screen is marked ... there is nothing you can do.

Get another screen
Pentax LX - Info on Various Focusing Screens


----------

