Dysfunctional (?) Canon 50mm f1.4 LTM

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seigik

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Nov 26, 2009
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Note: I'm a complete noob when it comes to RF cameras, but I've fallen in love with what I've seen so far.

The picture pretty much sums it up. This lens (50mm f1.4) and body (Canon Model 7) is my gramp's and I've been wanting to use it, but the lens is dysfunctional :(. As you can see, its in a perpetually open state. I have no idea where to get the lens repaired, how much it'll cost, whether its justifiable or not, etc. Please help! Thank you! I'd really appreciate any insight possible.

4136943091_68fba0748c.jpg


Sincerely,

Broke-Ass College Student
... who has fallen in love with a ridiculously expensive hobby
 
DO NOT TRY TO FORCE IT! You'll ruin the aperture blades very easily. Already I can see a non-circular opening in the aperture, this most of the time is not good...

I might be able to create a pictorial on cleaning a 50/1.2 Canon over the weekend. They are really easy to work on and mine has oil on the blades (as yours probably has, 'freezing' the aperture). If the 1.2 is anything like the 1.4 you can do it yourself if you move carefully and considerately.

FWIW, there are scores of other lenses that fit the Canon RF's so you can always start out with a different lens and have this repaired later if you choose not to put the craft in yourself.
 
I would love that! I have no problem with attempting to do it myself, but I may just be reckless.. Sounds exciting. haha.

Do you have any recommendations for other lenses I can possibly start out with?

PS. Can you please clarify what you mean by "DO NOT TRY TO FORCE IT"? Thanks!
 
seigik: it's not so obvious what is the problem when you say "the pictures sums it all". Could you please explain ?

CLE-RF: Canon 50/1.4 doesn't have circular aperture opening until f/8 or smaller. The blades are strange shaped and at f/5.6 or larger they form an octagon or an octagonal "star".
 
CLE-RF, I'd be very interested in that. I have a 50mm f/1.2 that's otherwise going to need to be sent off for a $130 CLA. Was having some trouble getting the retaining ring on the back off with my spanner though, darn thing just doesn't want to budge.

Seigik - It's a nice lens, if you decide not to repair it yourself it's probably worth having serviced by a professional.

As far as a replacement, a Russian Jupiter-8 (50mm f/2) is inexpensive and surprisingly good, I've been using one as my primary lens for some months now.
 
seigik said:
I love your shots on your site, btw. :)
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Thanks for the compliment, and welcome to the forum! Hope your stay will be a lenghty and productive one!

The advice is not to force the aperture ring, because the aperture blades are stuck. These blades are of the thinnest steel, less than a millimeter thickness and they have tiny, stamped-in notches to fixate them in the aperture mechanism and allow for them to open and close. You'll either tear the blades or rip the notches from them, leaving them useless. Spares will set you back another lens, they are virtually unobtainable.

El Cheapo substitutes are Russian RF lenses, Jupiter-8, Industar-61, Industar 26 (collapsible), and there also are many different Leica, Nikkor and Canon rangefinder lenses that go on that camera without any fuss. I shoot Komura screw mount lenses (also sold as Acall) and since they are not well known, you occasionally find them for netxt to nothing. In the USD 30 (Russian) to USD 100 (others, when lucky) you can find some nice stuff already.

In the Members section there's a Honorary X-mas thread right now, where we shed our surplus stuff for postage only, so keep an eye out there, lenses occasionally pop up there!
 
Spyderman said:
...

CLE-RF: Canon 50/1.4 doesn't have circular aperture opening until f/8 or smaller. The blades are strange shaped and at f/5.6 or larger they form an octagon or an octagonal "star".
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Possibly true, the aperture in the picture looks way off though. It's got five corners and not all sides are equally long or similarly shaped. Somethings definitely wrong there. Usually this means dislodged aperture blades. I've seen it on another 50/1.2 and when blades are bent or torn, it ain't pretty.

I fixed one 50/1.2 up that had three bades ripped, left the blades out. It had an acceptable aperture opening from wide open until 4.0, but after that gaps started to show up between the blades, so there was 'ghosting' on the lighter objects in shots. Sharpness dropped like a rock beyond 4.0, while it should increase there. Someone bought it through the classifieds to use the rear element in a restoration job.

@ ethics gradient: You're on! I'll put in my best coming Sunday.
 
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To Spyderman:
So, (this is before I knew I wasn't supposed to funk with the aperture at all) I've found that moving the aperture ring doesn't effect the aperture blades at all - in other words, no matter what f-stop the lens in on, the blades stay in that position.

To CLE:
Thanks for your detailed responses! Its really helpful; I appreciate it! And I'll keep my eye out on the x-mas forum ;)

To Ethics:
I'm definitely playing with the idea of having it professionally taken care of. I still need to decide whether or not I want to attempt to fix the lens myself (I probably will be more sure after seeing CLE's upcoming guideline).

I AM low on cash, so ideally I would fix it myself fo' free w/out destroying the lens. How much do you guys figure a repair would cost? And where would I get it done?
 
It'll cost $50 to $100 depending on who does the repair and what needs done to it. The lens in good working order is worth $300 so it is worth fixing unless there are scratches on the glass or other major defects that cannot be fixed.
 
Chriscrawfordphoto said:
It'll cost $50 to $100 depending on who does the repair and what needs done to it. The lens in good working order is worth $300 so it is worth fixing unless there are scratches on the glass or other major defects that cannot be fixed.
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If you got it free, spend the $$ on a CLA and you'll be very happy w/ it. It's one of the best LTM 50s ever made.
 
If the aperture blades won't move, it could be that the grub screws/set screws that attach the aperture ring to the underlying collar that is part of the aperture mechanism are loose or perhaps broken.

It could be as simple as tightening the screws. On the other hand, it could be a more complex job that would require a further breakdown. Or it's possible that it's irreparably broken. It's one of those things that difficult to diagnose without inspecting the lens in person.
 
By the way, rangefinder lenses don't snap open or closed at time of exposure. They're always at the indicated aperture. There's no need to close them down at exposure, because you're not viewing or focusing through the actual lens.
 
The aperture as shown in the photo looks "lopsided", meaning some of the blades have come off their guide pins. They need to be reset. This is not an easy job, and is best done by a pro.

This shop recently quoted a very reasonable charge for similar work:

http://www.dagcamera.com/
 
Brian Sweeney said:
The aperture as shown in the photo looks "lopsided", meaning some of the blades have come off their guide pins. They need to be reset. This is not an easy job, and is best done by a pro.

This shop recently quoted a very reasonable charge for similar work:

http://www.dagcamera.com/
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hi Brian,

you consider this a difficult job? I found it easy to do, perhaps I missed something? The Canon 50/1.2 really is a joy to work on, very simple, IMHO.

Does this mean I'm a pro? :D or just that I missed something?
 
Did you charge yourself for the work?

And yes- I consider it a difficult job for someone that has not taken lenses apart, and is doing so without a repair manual and step-by-step guide. It's worth paying DAg $65 or so to have it done professionally, as it is a $300 lens. I took apart a lot of junk lenses before taking apart the Canon 50/1.4 and Canon 135/3.5. The latter's doublet had separated. Fixed it.
 
I'll definitely look into DAG to see how much they'd charge me for a repair :) Thanks a lot for your help guys. I've snooped around a little bit, but I still don't know much about rangefinders in general, or my body/lens in particular. Any favorite websites, etc?
 
Cameraquest.com, the website and camera business from our Head Bartender!

When looking for the Canon 7 on Google you can pick the cameraquest listing out, it'll tell you all you need to know on the camera. The Photoetnography site by Karen Nakamura also is very good and informative.
 
Brian Sweeney said:
Did you charge yourself for the work?

And yes- I consider it a difficult job for someone that has not taken lenses apart, and is doing so without a repair manual and step-by-step guide. It's worth paying DAg $65 or so to have it done professionally, as it is a $300 lens. I took apart a lot of junk lenses before taking apart the Canon 50/1.4 and Canon 135/3.5. The latter's doublet had separated. Fixed it.
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My wife charged me for the work, complaining I took up the whole kitchen table and the whole Sunday afternoon :)

I will be creating a pictorial on Sunday on how to proceed with the 50/1.2 and am hoping more people will be able to fix it after reading that. I'll let you know once I've put it up, I value your opinion on my pictorial once its done.
 
I always vacuum the house- so do not get complaints about using the kitchen table.

I look forward to the pictorial. These are not enough of these "how to" guides around.
 
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