Ko.Fe.
Lenses 35/21 Gears 46/20
Not to mention what Leica M curtains aren't this fragile if they are in working state. And maybe OP has Bessa 🙂
Front focus - M mount
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Not to mention what Leica M curtains aren't this fragile if they are in working state. And maybe OP has Bessa 🙂
Mackinaw
Think Different
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I once watched a buddy stick a finger into the shutter of his Canon F-1 while loading it. Put a dent in the second titanium curtain. He was lucky, no impact on the shutter's accuracy. Of course I never let him live it down.
Jim B.
Halftrack
Member
You omitted the time it will take the OP to buy the ground glass, cerium oxide, and basic tools. If he's adept with Google and shopping online, shall we say 30-60 minutes? Pay extra for overnight delivery. Now we're up to 24 hours before he even starts cutting the glass -- something he's never done before. I suppose he can use the 24 hours to read online tutorials.
As I said, I can shoot and develop a roll of film in less time. Certainly less than an hour. Maybe you lack that option.
Someone else's suggestion to use a blank negative as a ground glass makes a little more sense -- if it's pressed flat enough with the loupe to show precise focus. Ground glass would be flatter.
The danger of damaging the shutter isn't from the ground glass resting inside the film rails. It's from the glass or a finger accidentally tipping out of the rails into the shutter while pressing it with the loupe and focusing the lens. When testing focus at various distances, the camera must be horizontal or nearly so, which means we can't rely exclusively on gravity to hold it in place. Your suggestion of taping it down would help, as long as the tape doesn't leave sticky residue in the film channel. Just because you have thought of all these things doesn't mean a person who's never done it before will do likewise.
I stick by my recommendation: Duplicate real-world conditions by shooting a roll of film that's already handy and doesn't require buying a locking cable release, ground glass, cutting tools, cerium oxide, and exercising some dexterity. It's the easiest, cheapest, fastest, safest, most realistic, and most precise method of checking focus.
awilder
Alan Wilder
I used to check M lens focus with a ground glass screen as it was useful tool to confirm accurate far and near RF cam roller calibration. Keep in mind the actual film plane focus is not at the inner rail but slightly behind as it "floats" within the 0.20 mm channel due to film curl since film thickness is about 0.145 mm. Typically, I would place a thin strip of scotch tape (about 0.05 mm thick) at the edge of the ground glass cutout to push its plane slightly back as it rests on the inner rails. For a ground glass cut out I would typically use a used Nikon B screen from their FM/FE series and cut off the small tab at the edge of the screen. To the center of the screen I would affix a 25x focusing loupe that Modern Photography supplied with their USAF resolution test chart kits and adjust so it's sharply focused on the center of the screen. Once assembled, I had a handy tool that could quickly check focus to determine if the camera's roller cam was properly adjusted for various lenses. Here's one available on eBay: https://www.ebay.com/itm/How-to-TES...245345?hash=item59687f09a1:g:8HMAAOSwojRgRRB6
awilder
Alan Wilder
Does your lens in question give perfect RF coincidence at infinity? If coincidence is perfect at infinity and the lens doesn't front focus at infinity but rather front focuses at close distances, the camera's cam roller arm length position needs tweaking. If the problem is only with that lens as compared to another 50 or a 90, the lens is suspect.
Sonnar Brian
Established
http://www.pentax-manuals.com/repairs/j3service.pdf
I prefer a Canon 7 for testing lenses, "T" setting on the shutter. I always use a heavy tripod for the camera while making the measurements. No problem with sticky residue.
You can see the setup I used for measuring focus. Since this time, I picked up a TTL viewer for LTM lenses, and the Digital Leica bodies.
I prefer a Canon 7 for testing lenses, "T" setting on the shutter. I always use a heavy tripod for the camera while making the measurements. No problem with sticky residue.
You can see the setup I used for measuring focus. Since this time, I picked up a TTL viewer for LTM lenses, and the Digital Leica bodies.
The problem with shooting a film (which I'm not sure you appreciate) is that, yes, it can inform whether or not Eg your rangefinder matches your lens but it's of little practical help in actually correcting the fault.
What I mean by that is if, for example, the focus adjustment of a lens is off your film results will inform that. But in order to correct it you'll need to adjust the lens infinity stop, focus knob position, shim thickness behind the shutter (depending on the type of camera) and then, re-check the adjustment. In the case of certain types of cameras (Eg vintage folders using shims to set infinity), having to Eg substitute a shim, take a develop some test images, examine, and re-adjust until good: would be extremely tedious, to say the least. Now, I *like* shooting film. Except for some photos of vintage camera stuff and quick phone record images I don't really shoot digital. Film is *great*. But shooting off a frame every time a calibration is done until a camera is good is...not an intelligent use of one's time.
You keep going on about the time needed to make a ground glass. Well it takes time to process a film, too. The salient point is that once a glass has been made you can use it again, and again, and again.
Halftrack
Member
You make good points if the person who checks focus also intends to recalibrate focus. I'm assuming the OP (who wasn't even sure how to check focus) isn't going to attempt his first recalibration by experimenting on a Leica. It requires proper tools and expertise. Mistakes can be expensive.
Among the most popular independent Leica repair people, my understanding is that Don Goldberg (DAG) has a collimator for this purpose; maybe Sherry Krauter does; but I think Youxin Ye does not.
For someone without a collimator or digital Leica, shooting one roll of film that includes pictures of an oblique ruler will confirm whether the camera-lens combinations are focusing correctly and whether any error is front- or back-focus. Those pictures will also be useful guides for the repair person.
DAG asked me to provide such pictures when my 50mm Summicron (now under his care) suffered an accident and lost calibration. I have an M10, so I sent him the digital files.
Apparently you are experienced in this field, so maybe you can suggest what happened to my lens. It's a 1969 model I've owned since the 1980s, and it has always focused flawlessly at all distances on my film Leicas and M10.
But in November, a car seat and heavy suitcase fell on my camera bag with such force that it loosened the removable Visoflex head. (I had never removed the head and didn't even know it was removable.) Otherwise, the lens appeared unscathed. Ditto for the camera. But I soon discovered the lens no longer would focus at infinity and that f/2 infinity pictures were unsharp. All my other lenses continue to focus correctly, so I ruled out the camera.
I sent the lens to DAG, who turned it around unusually quickly. Now it focused at infinity, but I discovered it was way off at closer distances. My test shots of a yardstick revealed about six inches of back focus.
DAG agreed to fix it again. I returned it in November but haven't heard from him since.
What I don't understand is how an apparently undamaged lens can be so far out of calibration. The lens mount and cam look normal. My only theory is that perhaps some glass elements became decentered or even separated. The back focus looks consistent across the field, however. Nothing rattles when I shake the lens. Any ideas?
Hi
It is not easy to pinpoint the actual problem without being able to examine the items, but I think you may be heading on the right track, here (highlighted, above). Why? Well, it sounds as if the lens is now focusing OK at infinity.
So, what would cause it to deviate from the rangefinder at closer distances? Well, it has a cam that Leitz precisely ground to match its exact focal length. This ensures that, as the focus distance is decreased, the rangefinder tracks accurately with the lens. If it is no longer doing this with the same level of accuracy, (and this behaviour is repeatable with it fitted to different camera bodies) then—one logical conclusion, is that the impact the lens suffered has altered the focal length slightly. You'd likely not see this at infinity, but the closer you focus, the further the rangefinder and lens will deviate.
As to why this has happened, I can only speculate. Perhaps an element or element group has shifted internally just enough to alter the focal length? The only way to find out will be to disassemble the lens, examine and correctly reassemble. You won't find a finer technician than Mr Goldberg. By measuring focal length before and after he should be able to pinpoint this (as well as de-centering of course) and restore the lens to its original focal length. But in essence, logic dictates that, somehow, the impact has caused a subtle alteration in focal length, yes?
Cheers
Brett
peterm1
Veteran
I have a Canon LTM 50mm f1.2 which until I had it fixed was front focusing terribly. I mean feet in front of the focus point! I originally though that it was due to someone disassembling the helicoids and putting them back together wrongly but the technician I consulted discounted this for reasons I cannot recall. When the technician and I fiddled with it, it turned out that the focus shim was WAY too thick (and yes, it looked like an original factory shim not some dodgy replacement).
This raised a bigger mystery - how did this lens end with the wrong shim? Did it come from the Canon factory like this? If it did come from the factory like this how was it not picked up by quality assurance?
Or was it sent in for servicing at some point and a distracted technician replaced the wrong shim in it?
In any event my technician lapped the shim until focus was spot on using my M8. He said he had to remove perhaps 3/10th of 1 millimetre, which in optical terms is enormous. Now it is perfect.
All I can say is strange things happen in the life of lenses. Some of them are inexplicable.
This raised a bigger mystery - how did this lens end with the wrong shim? Did it come from the Canon factory like this? If it did come from the factory like this how was it not picked up by quality assurance?
Or was it sent in for servicing at some point and a distracted technician replaced the wrong shim in it?
In any event my technician lapped the shim until focus was spot on using my M8. He said he had to remove perhaps 3/10th of 1 millimetre, which in optical terms is enormous. Now it is perfect.
All I can say is strange things happen in the life of lenses. Some of them are inexplicable.
JoeV
Thin Air, Bright Sun
Halftrack: You're a newcomer to RFF, with only 7 posts. I'm curious why you're so adament in your viewpoint, instead of being humble enough to respect the experience of people here who've been working on RFs for decades.
Halftrack
Member
I'm new to this forum but not to photography or to RF cameras. I've used many different RF cameras since the 1970s and Leicas since the 1980s. I've written magazine articles about Leicas. They are no mystery to me.
I joined RFF hoping to find recommendations for more repair options. So far, none. Are there really people in this discussion thread who have been working on RFs for decades, as you say? Specifically, have they been working on Leicas? If so, I'm one of many people who would like to know if they offer service on current and older Leica cameras and lenses. Surely you must know that only a handful of reputable Leica repair shops are operating in the USA and they are backlogged for months.
In another RFF thread, someone claimed that numerous technicians as good as Don Goldberg (DAG) are available. When I asked for names, I got none. In another Leica discussion group (RedDotForum), someone recently asked the same question because his Leica needs a focus calibration. (Leica USA quoted him five months' turnaround.) Weeks have passed and no one has answered him, either.
The three top independent Leica repair shops in the USA are DAG, Sherry Krauter, and Youxin Ye. They seem to be one-person shops, and they all have more work than they can handle. Some folks in this thread imply that recalibrating a Leica lens is simple, yet I'm having trouble getting it done. Youxin said he couldn't do it at all. Sherry said she's too busy with cameras to bother with lenses. DAG failed on his first try, and it's going on four months since I returned my lens for another try. Not so simple, is it?
Instead we debate whether the best way to check focus is to take actual pictures or to manufacture a ground glass to insert in the film plane while locking open the shutter. We don't need confirmation that a lens isn't focusing correctly. The pictures already show that. And even if someone goes to the trouble of making a ground glass, it won't fix anything. Unless that person is up to the task of experimenting on a Leica, a reputable repair service must be found. Preferably one that's prompt.
If you know of experienced Leica repair shops with fast turnaround, please speak up, for the benefit of everyone.
Sonnar Brian
Established
The worst 5cm F2 Summicron I've seen had three inner elements inserted backwards. That took a while to figure out. I've never seen another lens that was this misassembled. The optics were jammed solid into the fixture so tight that one fractured when taking it out. Took a lot of trial and error to sort out the optics, and I used a TTL viewer to do it. Likewise with Jupiter lenses- I've done over 200 of them, and would get curve balls all the time. Converted 50 pre-war Sonnars to Leica mount, and worked on many lenses in Nikon S-Mount and Contax mount. I've had a couple of lenses sent to me after Henry Scherer worked on them- the focus did not match the RF. Wartime Sonnar in Leica mount and a Nikkor 3.5cm F2.5. It's not easy, I don't work on them anymore- refer people to Skyllaney in the UK.
Using film was fine for a final test before returning the lens to someone, or putting one up for sale. Once I had the M8, bought 11 years ago, quit using film for focus checks. It was impossible to rely on tests on film to repair and adjust lenses. I even have a Nikon collimator. It is heavy. For digital- used my M9 for most. For an M Monochrom, would ask what contrast filter was likely to be used. You need to thicken the shim for use with Yellow-3 (Y52) and deeper.
Using film was fine for a final test before returning the lens to someone, or putting one up for sale. Once I had the M8, bought 11 years ago, quit using film for focus checks. It was impossible to rely on tests on film to repair and adjust lenses. I even have a Nikon collimator. It is heavy. For digital- used my M9 for most. For an M Monochrom, would ask what contrast filter was likely to be used. You need to thicken the shim for use with Yellow-3 (Y52) and deeper.
dourbalistar
Buy more film
I've been on the lookout for similar information, for similar reasons. Of course DAG, Sherry, and Youxin Ye are well known, but they all seem slammed with monthslong repair backlogs.
One repair shop that I saw recently is Red Dot Repair, a (new?) repair shop in Oregon. No personal experience, so caveat emptor. Among other repairs, it seems they also offer cover glass replacement for the M9, which from what I understand is not a trivial job.
https://www.instagram.com/reddotrepair/
Halftrack
Member
Yes, that's why I'm trying find reputable, experienced Leica repair shops besides the aforementioned three people who are backlogged for months. I paid good money for my Leica cameras and lenses and don't want self-styled "experts" monkeying around with them.
It's frustrating that only one repairman in the entire USA is willing and able to recalibrate my 50mm Summicron. And almost four months have passed since I sent it to him. I gave up and just bought another 50mm lens. I'm thinking about duplicating all my other focal lengths as well. I'm also expanding my search for repair shops to foreign countries. Even if the international shipping takes longer, the overall turn-around might be shorter if they're not so backlogged.
If I find some good repair alternatives for Leica equipment, I will share them on this forum. As I suggested earlier, it would be useful for RFF to create a "sticky" thread listing Leica repair shops and perhaps some comments on the quality of their work.
Neist
Newbie
Myself and a few people I know in the New Jersey/ New York area have been using some UK based repair and repaint shops in the last year. Their turn around times seem to be quicker then the US based ones. I get the feeling people simply cant accept the 12+ month turn around times on repairs anymore and are simply going abroad now.
Often the equipment sent from the US can enter into the UK on a ‘repair and return/ temporary import’. This avoids customs charges and taxes.
There is:
PPP camera: https://pppcameras.co.uk/
Pierro there fixes cameras at a rather affordable price and turn around time.
On his IG, the amount different cameras he has serviced is quite vast.
—
Skyllaney Opto-Mechanics: https://skyllaney.com/
Kris there repairs Leica, Voigtlander and Zeiss rangefinder lenses. He also converts non-rangefinder lenses to become rangefinder lenses. They also seem to be developing remakes of old lenses and have an in-house machine shop that makes parts for them. He has an IG account also, and is often posting very interesting conversions to Leica RF using Rollei, Summilux-R, Kodak Aero-Ektar and other lenses.
—
Cameraworks UK: https://www.cameraworks-uk.com/
Alan there repairs Leica cameras and lenses. They also do repaints.
Not sure if they are on IG. The repaints they do on Leica cameras are absolutely gorgeous, but Im aware they do take some time to finish.
—
Camerakote: https://www.camerakote.co.uk/
Aaron repaints cameras, lenses and other items (Typewriters, Guitars..etc).
He’s done a ‘Boba Fett’ themed Rolleiflex, ‘Darth Vader’ themed CZJ Sonnar, and has pictures of gold plated Nikons on his IG account. He paints Rolleiflex 35S cameras in a variety of colours also.
—
While I’ve mot dealt with all of them above, Ive dealt with some of them, and the ones I have spoken and worked with were all very professional and knowledgeable in their fields of expertise. As mentioned though, these are all UK based shops.
Here in the US, aside from the main three, Jadon Rosario (Red Dot Repair) seems very competent. There is a video created by Matt Day about some work that Jadon did on his Leica M6 for him, which he sings much praise for.
Jadon can modify the Leica film cameras also to suppress frame lines if you desire, and can add something into the M6 to stop making it flare.
Often the equipment sent from the US can enter into the UK on a ‘repair and return/ temporary import’. This avoids customs charges and taxes.
There is:
PPP camera: https://pppcameras.co.uk/
Pierro there fixes cameras at a rather affordable price and turn around time.
On his IG, the amount different cameras he has serviced is quite vast.
—
Skyllaney Opto-Mechanics: https://skyllaney.com/
Kris there repairs Leica, Voigtlander and Zeiss rangefinder lenses. He also converts non-rangefinder lenses to become rangefinder lenses. They also seem to be developing remakes of old lenses and have an in-house machine shop that makes parts for them. He has an IG account also, and is often posting very interesting conversions to Leica RF using Rollei, Summilux-R, Kodak Aero-Ektar and other lenses.
—
Cameraworks UK: https://www.cameraworks-uk.com/
Alan there repairs Leica cameras and lenses. They also do repaints.
Not sure if they are on IG. The repaints they do on Leica cameras are absolutely gorgeous, but Im aware they do take some time to finish.
—
Camerakote: https://www.camerakote.co.uk/
Aaron repaints cameras, lenses and other items (Typewriters, Guitars..etc).
He’s done a ‘Boba Fett’ themed Rolleiflex, ‘Darth Vader’ themed CZJ Sonnar, and has pictures of gold plated Nikons on his IG account. He paints Rolleiflex 35S cameras in a variety of colours also.
—
While I’ve mot dealt with all of them above, Ive dealt with some of them, and the ones I have spoken and worked with were all very professional and knowledgeable in their fields of expertise. As mentioned though, these are all UK based shops.
Here in the US, aside from the main three, Jadon Rosario (Red Dot Repair) seems very competent. There is a video created by Matt Day about some work that Jadon did on his Leica M6 for him, which he sings much praise for.
Jadon can modify the Leica film cameras also to suppress frame lines if you desire, and can add something into the M6 to stop making it flare.
Beemermark
Veteran
In the US, there's also
Gus Lazzari, TLC Camera Repair
TLC Camera Repair
4554 Chestnut Street Ext.
High Point, NC 27265-8642
thegreatgus@gmail.com
office: (336) 307-2126
cell: (949) 275-0313
And here's another list
https://johnnymartyr.wordpress.com/2019/08/27/the-2019-leica-repair-tech-list/
However you can expect a waiting time of months for any Leica service, except Youxin Ye (and I wonder how he can turn them around so fast)
Gus Lazzari, TLC Camera Repair
TLC Camera Repair
4554 Chestnut Street Ext.
High Point, NC 27265-8642
thegreatgus@gmail.com
office: (336) 307-2126
cell: (949) 275-0313
And here's another list
https://johnnymartyr.wordpress.com/2019/08/27/the-2019-leica-repair-tech-list/
However you can expect a waiting time of months for any Leica service, except Youxin Ye (and I wonder how he can turn them around so fast)
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