Mamiya 645 super Help!

[monjue]

Hello all,

Ive joined the forum in the hope someone can help me with a focusing issue.

I have the mamiya 645 super. I bought it second hand. I have shot 3 rolls of film using 80mm and 55mm lenses.
All the photos i received back are clearly out of focus. It appears the camera is focusing behind the subjects.
I checked the 'mirror stop' and sure enough it had a crack in it. So i bought a few 3d printed mirror stops and did the replacement. Spring and mirror stop are correctly positioned.

However!... when trying to do the infinity focus calibration (i'm using a lamp post in the distance) no matter how much i adjust the mirror stop adjustment screw I cant get the lamp post to line up? The split on the lamp post do not pass each other, they simple can't quite meet up. I've maxed out the adjustment screw and still the split lamp post just don't quite reach each other.

Ive tried calibrating with both the 80mm and the 55mm, but neither of them will allow the lamp post to meet up. Both lenses show the infinity symbol in the correct position when the focus ring is rotated the the maximum position.
The focusing glass is seated correctly and everything else seems to be fine.

Is there something else i need to adjust apart from than the mirror stop screw? or any suggestions to what might be wrong?

Thank you to anyone who takes the time to read this and offer advice.

Monjue.

 

[shutterfinger]

There are several 645 Super service bulletins and a service manual for free download at https://learncamerarepair.com/productlist.php?category=2&secondary=22
I would start by placing a ground glass on the film plane with the shutter open and lens focused on an infinity target. A piece of plain glass or clear acrylic plastic cut to fit on the film guides at the image plane with strips of transparent tape next to each other without overlapping makes a good substitute, tape side goes toward the lens. The further away the infinity target the better. The moon is an excellent infinity target and when it isn't available I use the sun with the appropriate solar filter over the lens or rangefinder windows whichever I'm adjusting.
Set infinity focus at the image plane first then adjust the mirror and or the viewfinder screen to match the image plane.

 

[Leolab]

Sometimes it looks like the mirror stop is in one piece when in fact it is broken.
Mirror stop breaks are so common with the Supers and Pros that I would be surprised if any are left with intact mirror stops.
The issue you describe matches exactly with a broken mirror stop.
Best way to check is to gently push down on the small part of the mirror stop that the mirror hits (as if the mirror is hitting it), the part of the mirror stop with the adjustment screw should move with it (its one piece, or at least supposed to be). If the top piece is moved and the part with the set screw does not move with it then the mirror stop is broken and needs to be replaced.

 

[MattKing]

Mirror stop breaks are so common with the Supers and Pros that I would be surprised if any are left with intact mirror stops.

Never a problem with mine (a 645 Pro, and a 645 Super before that), or any of the others I have encountered.
However, the mirror stop was a regular service item for cameras that had high usage. So yes, there are cameras out there that were either not appropriately serviced when parts were widely available, or which have experienced sufficient wear to require a replacement since then.

 

[Leolab]

In my life i have owned 10 Pros and Supers (dont ask…), 9 of the 10 had broken mirror stops.
I still have 5 and all of them I had to replace the mirror stop, which is not too hard if you have a little dexterity and know-how.
You can get a new one 3-d printed and its as good as new

 

[MattKing]

In my life i have owned 10 Pros and Supers (dont ask…), 9 of the 10 had broken mirror stops.
I still have 5 and all of them I had to replace the mirror stop, which is not too hard if you have a little dexterity and know-how.
You can get a new one 3-d printed and its as good as new

Note to self - don't buy a Mamiya 645 Pro or Super from Leolab.
The mirror stops were designed to be the subject of regular maintenance (sort of like brake shoes) if your camera had high usage.
And then Mamiya stopped supplying parts.

 

[Leolab]

my bad Monjue

Looks like you already replaced the mirror stop…i should read more carefully.

make sure you did not tighten the screw that holds the stop in place too tightly, you should be able to push down on top of mirror stop and when released it should snap back into place easily due to action of the spring

if i remember correctly, if you cannot reach infinity, the mirror is too low in its resting position

 

[Leolab]

Note to self - don't buy a Mamiya 645 Pro or Super from Leolab.

Well, i’d be willing to wager that my M645s with replaced mirror stops will have fewer mirror stop problems than those whose original mirror stops are now 30-40 years old…In truth its a design flaw with the pros and supers, these mirror stops are small plastic parts cantilevered out from a pivot, that are intended to have both repetitive stress from mirror falling on them and a smaller constant stress from weight of mirror resting on them…in short something a small piece of plastic is not suited for over longer term. My 645e has a simple metal peg bolted to chassis that mirror falls on, much simpler design that may stress mirror more but that has not failed me once yet. Surely this mirror stop for the Pros could have been made from metal to ensure greater durability

 

[MattKing]

n truth its a design flaw with the pros and supers, these mirror stops are small plastic parts cantilevered out from a pivot, that are intended to have both repetitive stress from mirror falling on them and a smaller constant stress from weight of mirror resting on them…in short something a small piece of plastic is not suited for over longer term.

It really is a question of design philosophy.
Those cameras were designed to have the mirror stops checked regularly and replaced if and when needed - a normal approach for a piece of equipment designed for the professional photography market.
The 645e was designed for a much lower usage environment, with the attendant reduction in expected service frequency.
No one designed anything back then (or now) with the expectation that parts that might be subject to wear or might be needing reasonably regular checking and adjustment would never require replacement.
Just as no one back then expected that there would be almost no film camera manufacturing in 2021.

 

[monjue]

my bad Monjue

Looks like you already replaced the mirror stop…i should read more carefully.

make sure you did not tighten the screw that holds the stop in place too tightly, you should be able to push down on top of mirror stop and when released it should snap back into place easily due to action of the spring

if i remember correctly, if you cannot reach infinity, the mirror is too low in its resting position

Thanks, the screw is not tight.. also even with the mirror stop removed and the mirror seated at its lowest position, it still can't reach infinity. So that goes against what you say about the mirror seated too low. For me the mirror is not low enough? even with the mirror stop removed!

 

[AgX]

A faulty mirror stop will basically only affect the upper part of the image, as at the other end, the hinge, the mirror will be more or less in right position.

 

[monjue]

A faulty mirror stop will basically only affect the upper part of the image, as at the other end, the hinge, the mirror will be more or less in right position.

So you're saying a faulty mirror stop does not effect focusing issues? Ive never heard that before.

 

[Leolab]

The mirror stop will definitely affect focus.

Has the focusing screen been properly installed? I know you say that it has been but i would double check again to make sure the correct side is up and it is properly seated.

also, you can use the mirror-up knob while looking through camera and with lens at infinity and with mirror stop removed. Move the knob ever so slightly in small increments to see if as you raise mirror the lamp post comes into focus. If it does it tells you that there is a position that will work at least. If there is no mirror position (between fully down with no mirror stop and moved upwards incrementally with mirror up knob) that allows infinity focus and you verified that focus screen is seated and oriented correctly, then I would wonder if the mirror support frame itself is bent or damaged…Perhaps putting mirror in up position and inspecting to make sure mirror bottom and hinges are undamaged and it seats flush whenin up position…

 

[monjue]

The mirror stop will definitely affect focus.

Has the focusing screen been properly installed? I know you say that it has been but i would double check again to make sure the correct side is up and it is properly seated.

also, you can use the mirror-up knob while looking through camera and with lens at infinity and with mirror stop removed. Move the knob ever so slightly in small increments to see if as you raise mirror the lamp post comes into focus. If it does it tells you that there is a position that will work at least. If there is no mirror position (between fully down with no mirror stop and moved upwards incrementally with mirror up knob) that allows infinity focus and you verified that focus screen is seated and oriented correctly, then I would wonder if the mirror support frame itself is bent or damaged…Perhaps putting mirror in up position and inspecting to make sure mirror bottom and hinges are undamaged and it seats flush whenin up position…

Yes, this is exactly where I am at. I have done what you have suggested and still infinity focus is not possible, I just wanted to confirm thats all i can really do without sending in for a check up/repair. Thank you for being on the same page.

 

[AgX]

So you're saying a faulty mirror stop does not effect focusing issues? Ive never heard that before.

Read more carefully what I wrote. Moreover you easily can check this with most SLRs.

 

[monjue]

Read more carefully what I wrote. Moreover you easily can check this with most SLRs.

Never mind i think im now where i need to be. But thank you for your help.

 

[Mamiya_Repair]

The mirror stops on Mamiya 645 Super, Pro and Pro TL are either in one of two states: broken or about to break. I say this because almost every one of these cameras that I see for a check up has a broken stop these days. Even if the camera has not been used much, the plastic mirror stop deteriorates and can snap with just a little use. If, after installing a new, correctly printed stop you can't get infinity (assuming the focus screen is set correctly) , then either the focus adjusting screw is installed incorrectly (the large head should be toward the inside of the camera) or the spring is not on properly. It is a bit difficult to install the spring on the body and I have seen them not correctly installed.

Just as a note, the process for checking and adjusting focus is to first adjust the mirror to a 45 degree angle and then to check focus at the fresnel screen and adjust if necessary. You can certainly check focus at the film plane also but there is no mechanism to adjust flange to film plane distance on the 645 Super as the body is milled to the correct distance and flatness.

 

[monjue]

The mirror stops on Mamiya 645 Super, Pro and Pro TL are either in one of two states: broken or about to break. I say this because almost every one of these cameras that I see for a check up has a broken stop these days. Even if the camera has not been used much, the plastic mirror stop deteriorates and can snap with just a little use. If, after installing a new, correctly printed stop you can't get infinity (assuming the focus screen is set correctly) , then either the focus adjusting screw is installed incorrectly (the large head should be toward the inside of the camera) or the spring is not on properly. It is a bit difficult to install the spring on the body and I have seen them not correctly installed.

Just as a note, the process for checking and adjusting focus is to first adjust the mirror to a 45 degree angle and then to check focus at the fresnel screen and adjust if necessary. You can certainly check focus at the film plane also but there is no mechanism to adjust flange to film plane distance on the 645 Super as the body is milled to the correct distance and flatness.

That's all good advice thank you. But what i can't understand is, even when the mirror stop is completely removed the focus still does not quite reach infinity? you would expect it to pass infinity with the mirror stop removed right? Thank you.

 

[monjue]

@Mamiya_Repair which 3D printed material do you recommend? My mirror stop is perfectly fine, but I am thinking about ordering a 3D-prited part and replacing it proactively because I've heard that sometimes, when your mirror stop breaks, the tiny spring can be lost. When looking at shapeways.com, they have multiple materials to choose from, but the descriptions are absolutely meaningless: some options are described as "strong" and others are "tough". No comparable numbers.

Probably best to start your own thread regarding this question.. just so mine does not get hijacked!

 

[monjue]

@monjue You probably have seen this, but sharing just in case. Nick Carver did a nice video showing the process of the mirror stop replacement and adjustment, which you can see and compare to your situation.

sure.. but that's not what my problem is.

 

[Mamiya_Repair]

That's all good advice thank you. But what i can't understand is, even when the mirror stop is completely removed the focus still does not quite reach infinity? you would expect it to pass infinity with the mirror stop removed right? Thank you.

With the mirror stop removed, the mirror will go the bottom of the mirror box and not allow infinity focus to be reached.

 

[Mamiya_Repair]

@Mamiya_Repair which 3D printed material do you recommend? My mirror stop is perfectly fine, but I am thinking about ordering a 3D-prited part and replacing it proactively because I've heard that sometimes, when your mirror stop breaks, the tiny spring can be lost. When looking at shapeways.com, they have multiple materials to choose from, but the descriptions are absolutely meaningless: some options are described as "strong" and others are "tough". No comparable numbers.

I use resin prints. Have inspected PLA prints, which is the most common and found them to be a bit too flexible for my liking.

 

[monjue]

With the mirror stop removed, the mirror will go the bottom of the mirror box and not allow infinity focus to be reached.

Sure, but wouldn't is see infinity be passed before i reached the bottom of the mirror box?.. what's happening is, if the mirror could go a couple of mm past the bottom of the mirror box infinity would finally be reached, but obviously that cannot be done. I would have expected infinity to be reached somewhere within the mirror stops adjustment screw 'zone'.

 

[MattKing]

Is there any chance that the problem is with the position of the focusing screen?

 

[Mamiya_Repair]

Sure, but wouldn't is see infinity be passed before i reached the bottom of the mirror box?.. what's happening is, if the mirror could go a couple of mm past the bottom of the mirror box infinity would finally be reached, but obviously that cannot be done. I would have expected infinity to be reached somewhere within the mirror stops adjustment screw 'zone'.

With the mirror stop broken or removed,

Sure, but wouldn't is see infinity be passed before i reached the bottom of the mirror box?.. what's happening is, if the mirror could go a couple of mm past the bottom of the mirror box infinity would finally be reached, but obviously that cannot be done. I would have expected infinity to be reached somewhere within the mirror stops adjustment screw 'zone'.

No, you would not pass infinity if the mirror is at the bottom of the mirror box as the mirror would be at an angle greater than 45 degrees. If the mirror was at an angle less than 45 degrees then you would pass through infinity.

 

[monjue]

Is there any chance that the problem is with the position of the focusing screen?

As far as i can see, there is only one place for the focusing screen. Ive inserted it a few times to make sure and it seems correct.