Cleaning a flattener

We needed to clean a flattener for a customer...

Tools required:

LensAid Fluid or Optical Wonder from Baader Planetarium as cleaning fluid
Lens-Aid Microfiber Swipes
Blows such as a Giotto

To make the dirt more visible, we used black cardboard.
 

The contamination can be clearly seen in the following picture.

 

Cleaning

Moisten a swipe with a little cleaning fluid (it doesn't have to be dripping wet, a little is enough; it goes a long way) and slowly (really slowly) wipe it over the dirty surface in one direction. Please do not wipe back and forth, as this may damage the delicate optical coating.

With the Baader Optical Wonder, it's best to use a blower to evaporate any remaining cleaning fluid.

The result
 

The marks on the back of the flattener on the left were of course also removed.