In order to convert your Mamiya RB67 to shoot old and new Polaroid Integral film, you will first need an Impossible Project Polaroid Lab.
The instructions below are designed for the conversion of the Impossible Lab into an Impossible Project Polaroid Back for Mamiya RB67 (only).
Before you start converting your Impossible Lab, I recommend testing the battery life. It’s no fun getting a polaroid frame stuck because of a dead battery.
By the way, the process is 100% reversible in case you ever want to go back to using your Polaroid Lab as a digital-analogue conversion device as it was intended to be use in the first place.
Let’s proceed to disassembling your Impossible Project lab (and keep a few parts). The suggested order to do this properly is:
- Use a thin bladed screwdriver / a box cutter (be careful with the fingers) to pry off the metal cover in the front of the Lab
- Use a #00 Philips Screwdriver to take off the back cover of the Lab. After you remove the two screws on the back (save them!), slide it towards the back and it’ll come out. Don’t pull it straight up, it has two notches on the inside that can break.
- The top is attached to the insides of the lab using two longer screws with Phillips #00 heads. Take them off, save them.
- The top is also attached to the front of the lab with two plastic tabs connected to two notches. Gingerly lift the top by sliding out of those notches in the front
- The top will also lift the dark slide, take it out but tilting it towards the bottom, it has two little hooks that prevent it from coming out normally. Don’t pull too hard, you’ll still need to disconnect a ribbon/cable, see next step.
- There’s a ribbon attaching the electronics board to a connector on the side of the camera. Carefully disconnect the ribbon from each side and save it.
- You’ll also notice a bent copper strip attached to the lab on the dark slide side. Don’t take it off, you’ll need it there.
- You will notice the eject/electronics board in the slot in the plastic top. Use tweezers/alligator pliers to carefully pull it out, and be careful not to damage any electronics.
- Save : the four black screws (from steps 2 and 3), the dark slide, the electronics/eject board, the cable ribbon.
You’re done with the first part! Now let’s attach the MUP/RB67 adapter. Examine the Impossible lab w/o the bottom/top parts first. You’ll notice two square holes in the front, these is where the two plastic connecting tabs in step 5 were pushed in. The replacement top also has two plastic tabs that will need to go in the same holes. So let’s begin.
10. First, use a pair of tweezers to reconnect the cable ribbon to the white connector inside the lab. The blue side should be facing the outside. While you’re at this step, notice the brass strip at the end of the lab. That’s designed to cover the dark slide slot when you remove the dark slide. Using your fingers, gently bend it UP a bit more that the way it is now. You want to be angled about 30 degrees, and as uniformly as possible.
11. Carefully slide the other end of the connector table though the slot on the side of the new top, and slide the new top on the lab, slightly angled, you should feel the tabs getting into the square holes in the front of the lab and the top should “snap” in place. Don’t force it if it doesn’t go easily, you may break the tabs.
After this first step, the top may be slightly angled up, that’s normal, it’s kept under slight tension by the front plastic tabs. Examine the inside of the square hole, it should be pretty flush with the inside of the lab.
12. Turn the lab around and use the screws you removed in Step 3 to attach the new top to the lab. Make sure they go all the way, but don’t overtighten them, you don’t want to rip the threads in the soft plastic.
13. Turn the lab around. We now need to attach the bottom. Examine the bottom on the underside, you’ll notice two little tabs, they need to slide over the edges on the lab. Place the bottom and carefully slide it in place, make sure it “clicks” and the front of the bottom plate goes under the front of the lab.
You’ll know you got it the top and the bottom edges align and you can see through the mounting holes in the bottom.
14. Use the screws removed in Step 2 to reattach the bottom
15. Now let’s attach the bracket holding the new eject/electronics board. It fits on the side of the new top, wrapping around the bottom of the lab, and it has 4 holes for mounting screws. It also covers the cable ribbon and has a slot for the cable ribbon to pop-up towards the new electronics box.
Route the cable ribbon underneath the bracket, pull it out through the top slot, and use 4 silver screws to attach it to the lab. They should go all the way in and the bracket should be pretty flush with the side and bottom of the lab.
16. The electronics/eject button board fits into a slot in the side of the new electronics board, you need to slide it in there. But first, attach the free end of the cable ribbon, the blue side needs to be facing the side of the white connector with two “ridges”. You can kid of see the electrical contacts inside the white connector, they need to touch the 4 metal tracks at the end of the ribbon cable. Push it in place, the ribbon will be _twisted_, then slide the electronics board into the side slot till it kind of clicks in place. Make sure the rest of the ribbon is pushed inside the box.
17. Close the side of the box using the side cover. It has two little hooks to grab the inside of the electronics box, so you’ll need to first insert the left side (there’s an inverted L printed on the inside), then push it in, it’ll snap in place. Adjust its positions so the edges are parallel with the sides of the box
18. You have two blue eject plastic buttons in the kit. One is a spare. Push one of the buttons from the underside (there are two side hooks, they should be pointed down when installed, that’s the underside) of the top cover in the corresponding hole. The large side should be on the bottom. Use a piece of tape on the OUTSIDE to hold it in place so it won’t fall inside during installation.
19. The top cover has two holes that the two holes in the eject cover side “ears”. Use the provided screws to attach the eject box top to the eject box.
Push on the eject button. If your lab is charged, it should make the eject sound and you should hear the eject arm snapping back in place. You may need to plug in your Impossible Lab at first in order to reset the electronics board in order for that to happen.
Also, attach the side cover of the eject box, match the inside lettering (R and L), by hooking in the R side first then pressing the L side closed. The cover is intentionally loose, use a few dabs of superglue on the inside corners to hold it in place. This will also allow you to take it off if needed in the future by simply prying it open.
20. Insert the dark slide, and fully charge your lab before use.
Optional:
There’s a “check dark slide” reminder plastic board in your kit. I used double side tape to attach it to the back right above the eject button. Attach it wherever you like if you want to attach it. I warmly recommend it, I’ve ejected many unexposed frames because I forgot to take out the dark slide.
Late build also come with a frames remaining “clock”, designed to Impossible Films and newer Polaroid Film (8 frames per pack).
You’re ready to shoot.
Don’t forget to take out the dark slide BEFORE you expose each frame. And place it back after your done shooting.!