Jared Lichtenberger Photography


Mamiya 645 Pro Mirror Stop Repair



In April, I purchased a used Mamiya 645 Pro online. Having previously owned a Mamiya 645 1000s, and not knowing much about the 645 Pro’s potential issues, I payed up without asking many questions. The photographer selling the camera made a comment like “I can’t seem to get images in focus. I guess my eyes aren’t what they used to be.” Well I’ve been shooting film for about 6 years now, mostly on a Nikon F3 and haven’t had much trouble nailing focus at even the shallowest depths of field. So I figured, that this was a non-issue for me.

Fast forward a few rolls of film, and I’m getting scans back from the lab with a consistent issue of back-focusing. In other words, I know I had the focus correct, but the resulting image shows the camera’s lens was focused beyond where I wanted it to be. In the photo of the cider can below, I focused the camera on the pink Eastciders logo, yet the resulting image shows the pull tab in focus. Again, in the photo of baby Liv and her grandfather, I focused the camera on the baby’s face and yet Pop’s shirt is in focus beyond Liv’s face.

Reading online forums, it became clear to me that the Mamiya 645 Pro is notorious for having a broken mirror stop due to a cheap plastic material that was used in the manufacturing of this part. This is hugely important because if the mirror stop is not properly positioned, the viewfinder and the film plane are in misalignment. So your image appears in focus within the viewfinder, but when the light hits the film the image is out of focus. My research revealed that Mamiya no longer services these cameras nor produces the part to have a camera technician do the repair. Many cameras that I saw photos of online had broken parts that were loose inside the camera body, but my mirror stop assembly appears to be simply bent to the side. I tried moving the piece back into its correct orientation and the whole piece broke in two.

Broken Mamiya 645 Pro Mirror Stop

Broken Mamiya 645 Pro Mirror Stop

I took my camera to Precision Camera & Video in Austin, TX to see if they could do anything that would put my camera back in working order. Unfortunately, without the part they couldn’t do anything for me. Their best advice was to look for a Mamiya 645 Pro camera body that was being sold for parts and to snag the part I needed from that camera.


Fortunately for me, just days after talking with the repair folks at Precision Camera, a guy by the name of Ványi Dániel Attila from Budapest posted this in the Mamiya 645 Facebook Group:

If someone interested in it, I made a 3D file for printing a replacement mirror stop for Mamiya 645 Pro. I can not found a proper free to download version of it, so I made one. It is free to download and print it wherever you want to.

LIKE, WHAT GREAT LUCK ON MY PART! Now all I had to do was find someone to 3D print the part for me! Someone in the Film Photography Facebook Group referred me to Shapeways, a company that would allow you to upload the file straight to their website and give you an immediate quote. Their site allows you to choose the material and color of your 3D printed item. So I uploaded the file that Ványi supplied in the Facebook Group and they shipped the part to me for $15.12 total. Now, back to Precision Camera to see if they can make this thing work. I dropped off the camera on a Monday and received a phone call from the camera repair folks at Precision on that Friday saying that the repair was done and the camera was ready to be picked up!

Cropped in image of the 3D printed mirror stop installed

Cropped in image of the 3D printed mirror stop installed

If you made it this far in reading this blog post, I think you’ll agree with me that this is incredible. Even more so, if you’re a film photography enthusiast! Many cameras with outdated electronics and parts break, but have no way of being restored without the original manufacturer providing those replacement parts. The mirror stop part isn’t highly technical… It’s just a piece of plastic. But how incredible is it that a guy from Budapest measured and created a 3D printable file for this part, I was able to have the part printed for very cheap, and a camera technician at my local camera store was able to install the part and bring the camera back into focus! INCREDIBLE!

So, if you found this blog post and you’re looking to have this same fix done for your Mamiya 645 Pro, I’m providing links to some resources below! And if you feel so inclined, it would be super cool of you to tip the creator of the 3D printable file when you download the file from the link. If you’ve found this write-up particularly helpful and you now realize how much money you are saving by not buying a new M645Pro, feel free to throw me a couple BONE$ via Venmo @Jared-Lichtenberger or via PayPal at Jared.Lichtenberger@gmail.com.

BIG DISCLAIMER: Part of the mirror stop assembly includes a very specifically formed spring which holds the plastic mirror stop part in place. In addition to the spring there is also a small screw that keeps the assembly stable. When my mirror stop broke, I still had all of the pieces inside the camera and was able to simply replace the broken part while still utilizing the original spring and screw in the repaired assembly. If you have lost these parts or purchased a camera without these parts still inside, I’m not sure that you’ll be able to pull off this repair without salvaging the parts from another 645 Pro camera body.


  1. Download the 3D Printable file of Mirror Stop

  2. Create an account at Shapeways and upload the file

  3. Contact Precision Camera & Video for repair

Cheers and happy shooting!