[Canon F-1N] Adjusting the mirror angle - HELP!

[davorzup]

Hello everyone,

I have an enormous problem with my newly-purchased old camera. I have a Canon F-1N which is in pristine condition - clean focusing screen, AE Finder which has barely been used, body that is (almost) without signs of use... and a problematic mirror.

Here's the thing: if I put on my FD 50mm @ f/1.4 and focus on someone's eyes and take the photo... their ears will be in focus in the final scan. When I focus on infinity with ANY FD lens (24,28,50,85), the microprism will not show the infinity in focus, but rather slightly out of focus. Like I need to twist the lens a bit more, but can't. When I get my film developed and scanned, I can see that the infinity is indeed IN FOCUS. Apart from the F-1N, I also have a AE-1 and AE-1P and there are no focusing issues on those cameras with any lens.

I have taken the AE Finder off and looked directly through the focusing screen with a magnifier and I've concluded that the problem is not in the AE finder, but it must be a problem with the mirror not being aligned. Even when I look at the mirror with no lens, I have a slight feeling that it is not perfectly parallel to the base of the body. Also, the focusing screen is perfectly in place, correctly put in.

I can't seem to find a person in Croatia or this part of Europe that can fix my camera... literally adjust the mirror to the proper angle. Does anyone have any suggestions as to how I can approach this issue? I've found a picture online (literally only one picture) on this subject and I've attached it below. There is a small hex just below the mirror which I can reach, but I don't know how far to turn it or with what tools.

I hope this huge post has not been in vain, I know I've given too much info probably, but I really love this camera and want to keep using it. The only problem is this mirror.

Help me if you can 🙂 I can provide some test photos in a few days to make my point.

Thank you for reading!

 

[p.giannakis]

My thought will be to send it to a repair person to do it - quite a few in UK. More recently a reputable repair person refused to work on one of my Voigtlander cameras because it had signs of someone (possibly amateur) tried to 'fix it themselves'.


If you wish to go ahead and do it yourself, this is what i would do.
Get some ground glass and stick it to the film chamber. Set the camera on a sturdy tripod, put the tripod 3m away from a target (use a measuring tape to measure accurately the distance). Set the lens on 3 meters.

Make slight adjustments until the picture on the viewfinder appears in focus. Set the camera in B and check on the ground glass if the target is in focus.

Having said all these, i also need to tell you that i am not a professional repair person.

Good luck!

 

[davorzup]

My thought will be to send it to a repair person to do it - quite a few in UK. More recently a reputable repair person refused to work on one of my Voigtlander cameras because it had signs of someone (possibly amateur) tried to 'fix it themselves'.

I understand, but I'd need to know where I can send it. It would be great if someone knows a repair person in Berlin also!

If you wish to go ahead and do it yourself, this is what i would do.
Get some ground glass and stick it to the film chamber. Set the camera on a sturdy tripod, put the tripod 3m away from a target (use a measuring tape to measure accurately the distance). Set the lens on 3 meters.

Make slight adjustments until the picture on the viewfinder appears in focus. Set the camera in B and check on the ground glass if the target is in focus.!

This seems like a good plan, but I don't know if the only thing I need to do in order to adjust the mirror angle... is that hex in the picture I attached.

 

[Sarcophilus Harrisii]

Hello everyone,

I have an enormous problem with my newly-purchased old camera. I have a Canon F-1N which is in pristine condition - clean focusing screen, AE Finder which has barely been used, body that is (almost) without signs of use... and a problematic mirror.

Here's the thing: if I put on my FD 50mm @ f/1.4 and focus on someone's eyes and take the photo... their ears will be in focus in the final scan. When I focus on infinity with ANY FD lens (24,28,50,85), the microprism will not show the infinity in focus, but rather slightly out of focus. Like I need to twist the lens a bit more, but can't. When I get my film developed and scanned, I can see that the infinity is indeed IN FOCUS. Apart from the F-1N, I also have a AE-1 and AE-1P and there are no focusing issues on those cameras with any lens.

I have taken the AE Finder off and looked directly through the focusing screen with a magnifier and I've concluded that the problem is not in the AE finder, but it must be a problem with the mirror not being aligned. Even when I look at the mirror with no lens, I have a slight feeling that it is not perfectly parallel to the base of the body. Also, the focusing screen is perfectly in place, correctly put in.

I can't seem to find a person in Croatia or this part of Europe that can fix my camera... literally adjust the mirror to the proper angle. Does anyone have any suggestions as to how I can approach this issue? I've found a picture online (literally only one picture) on this subject and I've attached it below. There is a small hex just below the mirror which I can reach, but I don't know how far to turn it or with what tools.

I hope this huge post has not been in vain, I know I've given too much info probably, but I really love this camera and want to keep using it. The only problem is this mirror.

Help me if you can 🙂 I can provide some test photos in a few days to make my point.

Thank you for reading!

It's not an enormous problem, a fairly minor adjustment actually.
You really need to verify the body register is OK before adjusting the mirror. If it's not you're wasting your time adjusting the mirror to match. It sounds promising from what you've said but to be sure a critical examination at the film plane is best to verify. It ought to be OK, but, then, the mirror ought to be OK, too. . . it probably it will be fine, but point is don't assume.

The following page contains some information about how to check the film focus and also the finder. Once you're satisfied the film focus is good the mirror just needs to be set to match, but do ensure the focus screen installation looks OK, because that can create the same type of focus issue as a mirror at the wrong height.

If you follow Rick's suggestions for checking focus (see link below), note that it's best to fit a lens on the camera being used to inspect the one needing adjustment that is twice the focal length of that fitted to the one being corrected. The 85mm lens would be OK with the 50mm attached to the F1N but if you have a 100mm or 135mm, use that instead, the extra magnification will make it a little easier to detect small calibration errors.

If the finder won't reach infinity it means the distance from lens to focus screen is still too long. You'd raise the mirror slightly to reduce the overall distance from lens to image-forming surface to correct.

Being a pro camera I expect the F1N would have a mirror lock up. If it is progressive rather than up/down you can likely preview the effect of raising the mirror slightly, by gently rotating or sliding the lock up a little, to simulate the effect of adjusting its stop. Perhaps what I'm saying will make more sense, then.

It does sound a bit like you haven't done much if any repair work, because this check and adjustment is pretty basic stuff. If you're not confident of your abilities get a professional to do the work. But we all have to start somewhere I suppose so I'll leave that up to you and it is, obviously, at your own risk.

That's not a huge post either, by the way. Look up a few of my own, if you'd like examples of "huge". 😉
Cheers,
Brett
http://rick_oleson.tripod.com/index-123.html

 

[Sarcophilus Harrisii]

I understand, but I'd need to know where I can send it. It would be great if someone knows a repair person in Berlin also!



This seems like a good plan, but I don't know if the only thing I need to do in order to adjust the mirror angle... is that hex in the picture I attached.

Sorry, I don't have an F-1N here I can examine, and the diagram you've attached is not much help, as it is not big or detailed enough to interpret the schematics of the mirror stop. You'd possibly do better posting close up, sharp images of the mirror box with the mirror down and retracted (use the lock up, if needed, or B or T, to give good views of the actuator in both the raised and lowered position).
Cheers
Brett

 

[Sarcophilus Harrisii]

Further to the above it seems there may be a known issue with the mirrors of this model as it ages. It may be a simple adjustment. Don't overlook the possibility, though, that it's an indication of a need to have the camera serviced to really correct the deeper problem...
Cheers,
Brett
https://www.photo.net/discuss/threads/canon-f1n-slow-mirror-fix.485856/

 

[davorzup]

Brett, thank you for a detailed reply 🙂

I haven't done any camera repairs, other than taking apart the top of my AE-1 a year ago because I had to fix my winder - it was a very simple repair.

I will have my camera on Tuesday cause I left it at home, then I can take some close-up photos of the problem.

As for the film plane, if I understood you correctly, there is no problem with that 🙂 I had previously taken the camera to a repairman here in Croatia, but he didn't know how to adjust the mirror. He did notice also that the mirror is in need of adjustment (he applied the ground glass in place of the film plane.)

Anyway, I hope that this is the procedure: I take the camera back off and use the cable release to hold the shutter. then, through the back of the camera, I use small specialized tools to rotate the hex counterclockwise until I see a clear image? Is it recommended to go through the back or through the front? I suppose I will lower the mirror by doing so. I don't understand those little details in the service manual, "apply Aron Alpha 802* to the hex-head eccentric."

Thank you again, didn't expect such a fast response! I appreciate it!

 

[Dante_Stella]

Brett, thank you for a detailed reply 🙂

I haven't done any camera repairs, other than taking apart the top of my AE-1 a year ago because I had to fix my winder - it was a very simple repair.

I will have my camera on Tuesday cause I left it at home, then I can take some close-up photos of the problem.

As for the film plane, if I understood you correctly, there is no problem with that 🙂 I had previously taken the camera to a repairman here in Croatia, but he didn't know how to adjust the mirror. He did notice also that the mirror is in need of adjustment (he applied the ground glass in place of the film plane.)

Anyway, I hope that this is the procedure: I take the camera back off and use the cable release to hold the shutter. then, through the back of the camera, I use small specialized tools to rotate the hex counterclockwise until I see a clear image? Is it recommended to go through the back or through the front? I suppose I will lower the mirror by doing so. I don't understand those little details in the service manual, "apply Aron Alpha 802* to the hex-head eccentric."

Thank you again, didn't expect such a fast response! I appreciate it!

Aron Alpha 802 is essentially superglue and is used to secure the screw from rotation once set.

Dante

 

[davorzup]

Aron Alpha 802 is essentially superglue and is used to secure the screw from rotation once set.

Dante

Well.... Damn. How do I relax this superglue in order to move the screw in the first place? I'd feel a lot more secure if a professional did this... does anyone know a repair person in Berlin?

 

[Carlos Cruz]

You sure it's a mirror that's at fault? I'd check first if groundglass is installed properly

 

[davorzup]

You sure it's a mirror that's at fault? I'd check first if groundglass is installed properly

100% mirror. I don't know how I could install the groundglass (focusing screen) wrongly, as there is only one correct way to install it.

 

[raid]

The F1N deserves the best; go to DAG. There may exist several other excellent camera repair people who are known to do good jobs on F1N cameras.

 

[ForestCap]

"Like I need to twist the lens a bit more, but can't."

That means the mirror is lower than the correct resting position. Make changes to elevate the mirror's current resting position.

If the mirror is resting on a fixed foot (Like Pentax ME), you can even stick a patch of sponge (like the light seal material, but hard ones) on the foot to elevate the mirror's resting position, just trim the sponge's thickness to make it spot on...Of course the best way is to adjust the foot itself.

 

[Steve M.]

Fortunately, w/ a SLR, what you see is what you get, so a DIY repair should be doable. Are you sure the focus screen is fully seated?

 

[davorzup]

Fortunately, w/ a SLR, what you see is what you get, so a DIY repair should be doable. Are you sure the focus screen is fully seated?

Absolutely.

"Like I need to twist the lens a bit more, but can't."

That means the mirror is lower than the correct resting position. Make changes to elevate the mirror's current resting position.

If the mirror is resting on a fixed foot (Like Pentax ME), you can even stick a patch of sponge (like the light seal material, but hard ones) on the foot to elevate the mirror's resting position, just trim the sponge's thickness to make it spot on...Of course the best way is to adjust the foot itself.

This seems like a neat trick. I'd still be willing to pay money to have it fixed properly, but it will do, maybe.

Once again: I am looking for a repair person in Europe - best bet would be Berlin or somewhere in Italy.

 

[davorzup]

I found these guys, any recommendations? https://www.kameraservice-ostkreuz.de/

Anyway, I'm attaching the mirror hex that I took a photo of. Mind you, I took the back off and held BULB with my cable release. It seems untouched, who knows... Maybe it's best I send it to them. The camera is practically mint apart from that 🙁

 

[Sumarongi]

I found these guys, any recommendations? https://www.kameraservice-ostkreuz.de/

I've never heard of Mr Prügel's workshop, neither good nor bad, but his name is very funny, anyways 😀

 

[Mackinaw]

I found these guys, any recommendations? https://www.kameraservice-ostkreuz.de/......

Looking at his website, he doesn’t service Canon F-series, only A-series and EOS.

If you’re open to sending your camera to the U.S., you may want to consider Ken Oikawa, in California, who is a retired Canon repair tech specializing in FD and FL Canon’s. Ken does top-notch work with a fast turnaround. Google for contact info.

Jim B.

 

[davorzup]

Looking at his website, he doesn’t service Canon F-series, only A-series and EOS.

If you’re open to sending your camera to the U.S., you may want to consider Ken Oikawa, in California, who is a retired Canon repair tech specializing in FD and FL Canon’s. Ken does top-notch work with a fast turnaround. Google for contact info.

Jim B.

I'd love to, but first I have to ship from Croatia to US... and then back... and risk my country flagging it for customs.

I don't know. I need to find a contact there.

 

[Sarcophilus Harrisii]

I found these guys, any recommendations? https://www.kameraservice-ostkreuz.de/

Anyway, I'm attaching the mirror hex that I took a photo of. Mind you, I took the back off and held BULB with my cable release. It seems untouched, who knows... Maybe it's best I send it to them. The camera is practically mint apart from that 🙁

If their location can work for you, I would write to them, explaining that the camera is working well and the lens focus is known to be good, but the mirror angle needs correction, and ask them if they'll take a look. Considering the diverse range of single lens reflexes that they say they'll repair, I can't envisage how a basic mirror adjustment of your F-1N ought to challenge them. It's not like you need it to be completely stripped and repaired. Let us know how you get on though and if they won't help for whatever reason perhaps an alternative technician can be recommended.
Cheers,
Brett