Here goes. You will need:-
2 x small flat bladed jewellers screwdrivers
1 x small cross head jewellers screwdriver
Glass cleaning spray
1. Using the flat jewellers screwdrivers, start at one end of the triangular shaped locking clip, working the clip out of the groove. This is the end that is normally secured to the housing and not seen.
2. With the clip removed, gently pull the lens mount/backplate out from the main body, using the o ring grooves that seal the viewfinder into the housing as a grip. Do not lever or force. The lens holder has a sealing o ring and may be a bit sticky, but will ease out.
3. As the lens holder/backmount starts to come free, invert the viewfinder so that the eyepiece points towards the ceiling. There are a stack of lenses in the lens holder that will fall out otherwise.
4. With the lens holder free of the viewfinder, put the viewfinder down and remove the small o ring, lenses and spacers from the lens holder. Note the order and orientation of the lenses and spacers.
5. Using the cross head jewellers screwdriver, unscrew the two phillips screws holding the prism into the viewfinder.
6. In the viewfinder there is a second stack of lenses and spacer rings. Remove lenses and spacers, noting the order and orientation.
At this point everything can be cleaned. Use the dust blower to remove dust before reassembling in reverse order. Remember to grease the oring that seals the back of the viewfinder. Carefully replace the triangular clip, it will only fit one way.
Take your time. It is not difficult, but getting the orientation and order of the lenses wrong may lead to the viewfinder not behaving as intended when viewing through it.
No warranty expressed or implied! If in doubt, find someone who knows/done it before.
Edited by decosnapper, 05 May 2013 - 08:20 AM.