Light Seal Placement Guides

Mamiya M645 Mirror Cushions Placement Guide

Mamiya M645 Mirror Cushions Placement Guide

USCamera Light Seals | Kits | Foam Sheets | Leica Film Cameras
Mamiya M645 Mirror Cushions Placement Guide | USCamera Foam
Before doing anything, please read about seal removal and installation.
Also,this M645 mirror kit is always in stock.
Please contact us with any questions you may have. New parts, light seal kits and also downloads are added to our almost every day.

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Tech Note: Most camera body channel seals are installed starting at the hinge end, working towards the latch side until the seal is used up
You are installing an 3 piece kit for the Mamiya M645 series of film cameras.
Please note the mirror cushion is the straight seal. The other 2 seals fit on mirror frame beside the mirror. Those are foam seals and not cushions. They are applied to the mirror frame to prevent light leaks when using the waist level viewfinder. Mamiya found that when the mirror rose to the top and the shutter opened, stray light enter the mirror cage area could fog the film.  That was only occasionally and really depended on how close or far away from the camera user was from the waist level finder when the image was taken. Just FYI, later model M645 cameras were updated and the foam seals on the mirror frame where removed and seals were placed at the top of what Mamiya called the “reflection absorber leatherette” on the left and right sides on the inside of the mirror housing.  In the parts list the “reflection absorber leatherette” parts are SLS29161 and SLS29131. The techs at Mamiya found light leaks were more of common with the updated seals than when the foam seals were applied to the mirror frame. So any M645 camera in for service they added the seals to the mirror frame.

The images below should help you in placing these 3 foam pieces.

Please note it is easier to install the mirror cushion with the viewfinder removed. I can show you how that part is easily removed in a video, I will make available soon.

Mamiya M645 mirror and cushion

Mamiya M645 mirror cushion

Mamiya M645 mirror foam and cushion

Mamiya M645 mirror foam


About Gray

As a veteran attending National Camera's resident camera repair school in 1979, is where I found my true calling for the demanding yet extremely interesting field of photo equipment service and sales. For 25 years we grew every year. The staff and I serviced tens of thousands of film camera items, trained many technicians, met thousands of wonderful customers and truly had a fantastic time. Within 2 years of 2004, my service experience was devalued somewhat by the internet, film camera sales/service flatlined. Camera stores 50 times larger than mine were closing. I could see a new opportunity on the Internet. USCamera started as information site then became a family run internet business. Our mission remains the same, • Specialize in Vintage film equipment, mostly after 1958 • Knowledgeable • Provide quality products • Superior Service • Always available via phone - contact form – email All of us at USCamera look forward to serving you. Gray

2 thoughts on “Mamiya M645 Mirror Cushions Placement Guide

  1. Robert says:


    how are the seals and the cushion fixed to the body/mirror frame. Is there already some adhesive on the seals/cushion or is additional adhesive needed?

    Best regards,

    1. Gray says:

      Thanks for contacting me. The kits you are asking about are packaged with open cell foam with the adhesive already applied. Peel off the back from the foam to expose the adhesive. When installing these kit parts an adhesive delay is important to help with proper placement. More on adhesive delay in the removal and installation instructions here There is a placement guide for help on the installing mirror cushions and placing the seals on each side of the mirror. Look here

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