Mamiya 7 II rangefinder/focus out of spec.

Discussion in 'Rangefinder Forum' started by JosBurke, Mar 14, 2006.

  1. JosBurke

    JosBurke Member

    Nov 27, 2004
    Multi Format
    Having recently purchased a Mamiya 7 II with 80 mm lens (you know where!) and receiving my first transparencies it seems the focus is a tad off--looks to be focusing just a tad forward of what the finder shows--I've done a little google research and note that when the lens is set to infinity the rangefinder is somewhat off. I have popped the tiny little range finder cap off the back of the camera and adjusted the lower infinity adj. screw (brass mount) to be in focus with the lens set at infinity and focused upon a radio tower a half mile away--Hopefully this will rectify the issue---the other focus adjustment is dead on where it should be. I secured the screws with Loctite--Anyone else have similar issues with the Mamiya 7 models ??? BTW--I ended up turning the inf. adj. screw a good 1/8-1/4 turn !! Hope this is the correct adjustment method!!
    I'll try another roll of film!!
    Joe Burke
  2. john_s

    john_s Subscriber

    Nov 19, 2002
    Melbourne, A
    Medium Format
    I have done the same adjustment to a Mamiya 7. There was an article about the procedure on Mamiya's web site, but it is now removed. I used a bright star (or planet) when doing mine, since the tiny optical size made the vertical and horizontal discrepancies very clear. For anyone's future reference, I have copied the text of an article referring to the Mamiya site below. I don't remember where I copied it from. I did not have to soften any Loctite, nor did I re-apply any. I thought that Loctite did not seal in the presence of air anyway. Some camera use something like nail polish to lock adjustment screws, but mine have not moved since I did the adjustment a year ago.

    ====start of quote=======
    "Your comments on being informed on user serviceability are valid, and I would like to address them. As a photojournalist and old Leica user, I understand and appreciate many concerns voiced about being able to adjust the rangefinder under extreme conditions.

    I will review the adjustment possibilities of the Mamiya 7 RF with the EXPRESS WARNING that the camera rangefinder assembly CAN BE DAMAGED if adjustment is not properly performed. The following information is shared WITH THE ACKNOWLEDGEMENT AND ACCEPTANCE BY THE CAMERA OWNER THAT THERE IS NO LIABILITY OR WARRANTY IMPLIED BY MAMIYA OP, OR ANY OF THEIR AGENTS, AND THAT IT IS NOT RECOMMENDED TO SERVICE ANY MAMIYA PRODUCT BY ANY OWNER.

    If a camera is under warranty, we note that you should send the camera to us, because any user serviceability would void the warranty. Now that I hope our concerns are clear, on to the information requested in the above forum postings:

    The plastic cap at the back of the Mamiya 7 top plate must be removed (you might use an Exacto knife )with care being taken not to cut the body cover ( NOT A GOOD THING). We use a bit of sealant adhesive to secure the cover.

    You might need to replace it with a new plug ( cost from Mamiya America Corp $2.00 USD.) after adjustment is made, because you may cut or damage the plug.

    Once removed, there are two screws visible. This is where the delicate part comes in. To service it it properly, we remove the entire top cover and all related parts, which is one reason for the amount of our repair charges on RF adjustment. CAUTION In the field, this is neither desireable nor practical and DEFINITELY NOT for a consumer to perform.

    Once the two screws are visible, the bottom one is for infinity adjustment ( screwed into a brass looking part) and the top for horizontal image alignment(chrome on chrome). CAUTION You may see a shielded wire, which you SHOULD NOT TOUCH as it may be easy to cut or damage it. Then you WILL NEED to send the camera in for the top plate to be removed and the wire replaced.

    Both screws are very sensitive and are secured with a type of "lock tight" adhesive. DO ONE ADJUSTMENT AT A TIME.

    You first need to loosen the adhesive with a solvent like acetone. CAUTION This should be ideally applied SPARINGLY with a needle, and acetone should be used sparingly and not come in contact with anything especially the body cover. It will remove paint.

    Once the screw adhesive is loosened ( DO ONE AT A TIME ) VERY CAREFULLY USE THE APPROPRIATE SIZE SCREW DRIVER. CAUTION A wrong size stripped or bent driver head MAY DAMAGE the screw.

    CAUTION For infinity, the eccentric screw is very sensitive, and probably needs VERY SLIGHT ADJUSTMENT. You probably need LESS THAN ONE QUARTER turn for adjustment.

    Once adjusted, you need to re-seal the screw with A TINY AMOUNT of loctite. For RF image horizontal alignment, the top screw needs to be loosened in the same manner as above. USE VERY GENTLE adjustment as above, because turning it TOO FAR can DAMAGE THE ENTIRE RF assembly as there are sensitive and some NON-MOVING parts directly connected to the screw. DAMAGING THIS MEANS YOU NEED A NEW RF ASSEMBLY. $$$$. This is why we DO NOT RECOMMEND USER SERVICING.

    If you have any further questions, please e-mail us. I hope that this information explains what we do and why we do not recommend user adjustment.

    I know many photojournalists who use and abuse the Mamiya 7 in the field daily, and who do not need adjustment as mentioned in the above forum comments. However, in an effort to be responsive, we have shared this information with appropriate caveats."

    The material contained within quotes was extracted from the Mamiya USA Forum. It was written by the erstwhile Mr Martin Silverman. Please note that it no longer appears on the Mamiya Forum and that Mamiya USA may not sanction its use any longer which means that Mamiya may not repair any cameras damaged by following these instructions. I'm supplying these instructions with a HUGE CAVEAT EMPTOR. Use them at your own risk only.