Obsessive-Compulsive Disease (OCD)
I'm not saying you can't rub on the mirror, just that I wouldn't do it. It's aluminum metal atoms sputtered onto glass. It's VERY soft, softer that the soft coatings of yore. Lifting off a few atoms means a scratch. Now, this will not affect photo quality, but it will reduce focusing contrast.
Regards, Bob...
From: "Don Sanderson" <[EMAIL PROTECTED]>
Bob, What's an OCD?
And...... Is it OK to touch the mirror when doing this?
Don (Running and ducking!)
-----Original Message----- From: Bob Blakely [mailto:[EMAIL PROTECTED] Sent: Monday, November 22, 2004 7:14 PM To: [EMAIL PROTECTED] Subject: Re: cleaning focusing screen / pentaprism
Bob's OCD recommendations for cleaning bottom of MX pentaprism, screen, and mirror box:
1. Wash your hands. You're not a good OC if you don't. 2. DO NOT TOUCH THE MIRROR! It's a first surface mirror (Al is on top) and can be easily ruined. 3. Remove screen using proper tool, carefully bent tweezers can work, grip tab only, place in proper holder (grips only edges). 4. Turn the camera upside down and LIGHTLY blow particles off mirror with *light* compressed air. (I use purified, dry CO2). Do not blow directly on foam. DO NOT TOUCH THE MIRROR! 5. Hold a small piece of paper in front of mirror to protect it and to hold screen holder out of the way and blow particles off bottom of pentaprism with *light power* clean compressed air. DO NOT TOUCH THE MIRROR! 6. Wind a piece of professional lens cleaning tissue on a toothpick, add small drop of cleaning fluid and clean the underside of the pentaprism using the same method you would for a lens (circle of very small circles from center out.) Do not let wood scrape glass coating. DO NOT TOUCH THE MIRROR! 7. Hold a small piece of paper in front of mirror to protect it and dry and blow any tissue threads off with *light* compressed air. DO NOT TOUCH THE MIRROR! 8. Turn the camera upright. 9. Pick up screen by *edges only* and blow moderate power clean compressed air over both dry sides. 10. Add a drop of dishwashing detergent to a bowl of distilled water, mix, and place the screen in the water to soak for a few minutes. If you have an ultrasonic cleaner, this is where you use it. otherwise swish it around. Rinse several times in distilled water and blow dry with compressed air. 11. Replace screen. 12. Attach short cable release, set MX to "B", lock shutter open using cable release. This locks the mirror up to get it out of the way and to protect it, protect the foam and open the shutter to protect it. Blast the crap out of the inside, be careful of any foam. 13. Release the shutter and close up the camera.
If the mirror has crap on it that does no blow off, DO NOT TOUCH THE MIRROR! Take it to a professional who will replace the mirror if he ruins it.
Regards, Bob...
