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Corran
20-Aug-2011, 17:23
I've searched and searched, can't find anything.

I need to adjust the RF on my Crown Graphic but I don't have a Master Cam. All the literature I have found says you have to have it. But I don't!

Anyone know any tricks for this? Alternatively, if anyone has a Crown with the 152mm Ektar lens, can they tell me exactly how far from the front of the rail their infinity stops are? I think that would help, maybe???

Corran
20-Aug-2011, 17:26
Sorry, duh, the RF is the later top-mounted Graflex one.

BradS
20-Aug-2011, 18:06
on the top rangefinder, the cam is all the adjustment there is. You set the infinity stops according to the published method...and change the cam...that's pretty much all there is to do.

You might find the appropriate cam on ebay. There is a seller or two who specialize in selling parts for the Graphics.

The 152mm Ektar was a standard lens...so, cams exist.

Corran
20-Aug-2011, 18:09
According to this website:
http://lommen9.home.xs4all.nl/cams/index.html

There is a "master cam" as well as the lens-specific cam.

Since you can focus both with the front standard and the focus rail, the "master cam" I assume provides a set infinity so that you can adjust the infinity stops to that lens, and then the lens-specific cam adjusts the focus.

Doing as you say simply makes the near-focus way off from RF.

I have a 152mm cam, just not the "master cam."

Frank Petronio
20-Aug-2011, 18:12
Haha you're f-ed.

To set the front stops, focus on something out at infinity using a loupe on the ground glass, just like Ansel Adams and the other 15,328 togs here. Using a tiny screwdriver, set the infinity stops to hit the front standard. See, really easy! Infinity is a breeze.

Try the Graflex.org forum and beg someone to sell you the proper cam, then good luck sliding that little bugger into place.

Or make your own: http://graflex.org/articles/cave.html or http://graflex.org/articles/oakes/

Google is great, try it!

BradS
20-Aug-2011, 18:17
According to this website:
http://lommen9.home.xs4all.nl/cams/index.html

There is a "master cam" as well as the lens-specific cam.

Since you can focus both with the front standard and the focus rail, the "master cam" I assume provides a set infinity so that you can adjust the infinity stops to that lens, and then the lens-specific cam adjusts the focus.

Doing as you say simply makes the near-focus way off from RF.

I have a 152mm cam, just not the "master cam."

That guy is talking shit out his ass. Go read Frank's post above and visit Graflex.org. It really isn't rocket science. Journalists used and maintained this stuff in the 1950's - it is a very simple and easy camera.

Corran
20-Aug-2011, 18:29
Google, huh? Yeah I've been reading for about 5 hours. Simple to say on the internet. But regardless the RF isn't focusing accurately once it's closer than 20 feet. Are you saying the cam is screwed up?

A little less guile please.

Corran
20-Aug-2011, 18:32
BTW, there is two separate focusing mechanisms, the rail that you unlock under the lens and the focus knobs connected to the RF. I can set up infinity with the focus knobs in any position, therefore screwing up the RF. That's the problem and has not been adequately explained. With the focus knobs all the way back the camera is way out of adjustment closer than 40-50ft. Somewhere I read they should be out about .04 inches or something, which was for a different lens.

BradS
20-Aug-2011, 18:47
I have owned at least five crowns and three or four speeds. I know Frank has had more than a couple pass through his hands too.


read the proceedure at graflex.org. I cannot explain it any better.


Take a deep breath...slow down. THINK!

When the rails are (nearly) all the way back, then the lens should be focused at infinity. Your mission is to...


1) mount your camera on a tripod and point it at a big object at infinity.
2) un lock the front standard - so that it moves freely forward and back.
3) get a jewler's screw driver and loosen up the little, itty-bitty screws that clamp the infinity stops to the rail.
4) slide 'em aft and fold down the wings.
5) look at the ground glass and grab the front standard.
6) slide the front standard forward and aft on the rail...do not move the rail...move the front standard...until the big thing at infinite distance comes acceptably sharp into focus on the GG.
7) lock it down and slide the infinity stops forward. I mark the position on the rail with a sharpie first because, you'll probably need to move the front to tighten the little, itty-bitty lock screws.

notice I didn't say anything about the RF yet.

once you get the infinity stops correct, pop in the cam and you good to go.

Corran
20-Aug-2011, 18:58
No where before did I read that you have to have the cam out when you focus at infinity, unless I missed it. Is that correct? I assume since you said to put it back in after focusing at infinity.

A simple "you have to have the cam OUT when focusing at infinity" would have saved a lot of time frankly, and no need to berate me. I understand you and Frank know plenty, which is why I am ASKING here. I don't need to get chastised because I don't know something and therefore came and asked!

BradS
20-Aug-2011, 19:28
Cam in or out....when setting the infinity stops does not matter. The cam only affects the range finder. When setting the infinity stops, the range finder is not involved at all. You focus using the GG on something at something at infinity.

Sorry if what I wrote sounds harsh. I'm not berating you. I'm trying to help...really... I'm frustrated because it really is not difficult and it seems like you're making it much harder than it is.

Do you have distance scale on the bed? Even if for another lens...move the focus knob so that the distance scale on the bed says "infinity". Now LOCK the bed so that it does not move. From now on you "focus" bu moving the front standard - by grabbing it and sliding it along the rail. Follow the proceedure I wrote above. (Or better the one at graflex.org).

Frank Petronio
20-Aug-2011, 19:34
I know so much that I can't retain it... sorry, just kidding.

But... relax. The deal with the top rangefinder Graflexes is that you generally don't touch them other than to set infinity stops and insert the proper, factory-made cam into the right place.

Simply inserting the right cam properly is super-hard for me. As for taking tools to it, my knowledge has evaporated and I'd turn to Graflex.org for the real experts.

The link you referred to is kind of wacky... I guess that is the danger of Google, you can stumble upon bogus info.

BradS
20-Aug-2011, 19:37
OK. I guess I am assuming that your camera's RF was set up for some lens...yes? That is, the RF is/was accurately adjusted for some lens, say a 135mm Optar or something...yes?

Further, I assume that you have not moved the little black arm on the rear left side of the focus rail - the arm that pushes on the "fat pin" that accuates the RF.

Are these assumptions true?


The "master cam" that Lomen speaks of is only necessary if the assumptions I have stated above are NOT true.

Please tell me, you haven't moved the little arm...have you?

BradS
20-Aug-2011, 19:39
Simply inserting the right cam properly is super-hard for me.


funny...that is the hardest part for me too (I have big dairy farmer hands and fingers).

Jim Jones
20-Aug-2011, 19:44
You don't have to remove the cam to do the procedure Brad describes. Nor do you have to look through the rangefinder to set the infinity stops. Make sure you have the right cam. No. 8 is for 150.3mm, No. 9 is for 152mm, and no. 10 is for 153mm. If Brad's procedure doesn't give you the correct rangefinder operation, there is a remote possibility that your Ektar isn't exactly 152mm. This could happen if it has been remounted in a shutter with the wrong cell spaceing. More likely there is a problem with the linkage from the bed of the camera to the rangefinder. Perhaps it is the adjustment of the black arm on the left (as viewed from the camera back) inner bed that Brad mentioned. It also could be the flexible cable that extends from the bed to the rangefinder. It is filled with tiny balls or dumbbell shaped pieces that can get lost.

Edit: While I was researching this, Brad & Frank posted above. I would do one thing differently than Brad. I would rack the focusing all the way back and set the focusing scale to infinity. Then I would set the infinity stops, using the ground glass and a very distant subject. That way I can focus on infinity without looking at scale, rangefinder, or ground glass. Then I would tinker with the rangefinder and perhaps its linkage.

Tim k
20-Aug-2011, 20:04
Another approach, would be to put a small piece of black tape over the little hole you look through. Then just use that big 4x5 piece of glass. Your going to look at it anyway, if you really care about the shot.

Ivan J. Eberle
20-Aug-2011, 20:40
Tim, there's absolutely nothing wrong with having an dead-nuts accurate RF. I find a lot of situations and techniques that call for RF focusing. Using a handheld Graflex or other press camera with a rollfilm back or a Grafmatic will be a breeze with a RF and a pain in the neck without. The Kalart side mounted ones with Focuspots are also pretty easily adapted to laser pointers for nighttime and twilight use when it's almost impossible to focus with the GG.

Frank Petronio
20-Aug-2011, 20:41
He's trying to do handheld photjournalistic shots with a Crown Graphic, like a real press photographer, so while the ground glass focusing is always the most accurate, it's not very practical.

Corran
20-Aug-2011, 21:10
Further, I assume that you have not moved the little black arm on the rear left side of the focus rail - the arm that pushes on the "fat pin" that accuates the RF.

Are these assumptions true?


The "master cam" that Lomen speaks of is only necessary if the assumptions I have stated above are NOT true.

Please tell me, you haven't moved the little arm...have you?

I have not to my knowledge...

BUT...this Crown was damaged in shipping (one of the tabs on the back to pull up on it was cracked right in half). The camera obviously took a large blow in shipping. I found at first the RF was grossly out of whack at infinity as well as close up. At this point all I have done is adjust the infinity stops, which were way off too, and then adjust the mirror to line up the spot in the RF. Nothing else. And no matter what I do the RF is way, way off closer than 20ft at best.

I need to double check the cam, but supposedly this RF was calibrated before I bought it so I am only assuming it has the correct one. But I'm doubting it was calibrated.

Corran
20-Aug-2011, 21:18
Well that'll teach me to trust a seller.

The cam is for a 135mm lens.

I should have checked that before I asked but I was told this Crown was just calibrated for good RF focus. Obviously that's BS.

Leigh
20-Aug-2011, 21:37
BTW, there is two separate focusing mechanisms, the rail that you unlock under the lens and the focus knobs connected to the RF. I can set up infinity with the focus knobs in any position, therefore screwing up the RF.
The locking rail is not a "focusing mechanism". It's a storage mechanism.

ALL focusing is done with the knobs.

The front standard should be pulled out to the infinity stop and locked in place. There is no other correct position for it. The infinity stops fold down so you can install more than one, to accommodate multiple lenses. (Apparently some don't fold down, although I haven't seen such.)

In this position the infinity focus of the rangefinder should agree exactly with the focused image on the ground glass.

I set these up so the infinity focus has the mechanism slightly forward. Your .04 inches (= 1 mm) is about the value I use.

I set the rangefinders using a military LM-63A 48" collimator which is designed expressly for this purpose. It was built by Kalart specifically to set their side-mounted rangefinder, but it works equally well for the Graflex-manufactured top-mounted unit. It has calibrated targets at 4 feet, 10 feet, and infinity, as required to set up the Kalart unit.

- Leigh

Frank Petronio
20-Aug-2011, 23:39
Corran, I am not trying to be a wiseass but if it's this hard, just get another Crown and from a decent seller who knows what they are selling.... Stephen Gelb has a $500 mint one in the classifieds right now, he is honest and it looks like a champ. It's worth a premium to buy one you know will be good.... But if you are patient on eBay you can take a chance and if you have a lick of sense and luck you can get a clean one for $250. Hell buy three and sell the dogs, that's what people do with lenses all the time.

If you get stuck with this Crown and the rangefinder is junk, then use it as a ground-glass only camera or for parts. Or just resell it with a good honest description and photos, you can probably get most of your money out of it and it's cheaper than chasing down old men for their last $100 P-84.7 Graflex cams or pulling your hair out with insane internet instructions....

OR let's all send our cameras to Leigh so he can use his military LM-63A 48" collimator... That would be awesome!

Tim k
21-Aug-2011, 06:21
Tim, there's absolutely nothing wrong with having an dead-nuts accurate RF. I find a lot of situations and techniques that call for RF focusing. Using a handheld Graflex or other press camera with a rollfilm back or a Grafmatic will be a breeze with a RF and a pain in the neck without. The Kalart side mounted ones with Focuspots are also pretty easily adapted to laser pointers for nighttime and twilight use when it's almost impossible to focus with the GG.

You are right nothing wrong with it at all.

Tim k
21-Aug-2011, 06:25
He's trying to do handheld photjournalistic shots with a Crown Graphic, like a real press photographer, so while the ground glass focusing is always the most accurate, it's not very practical.

Frank, I missed where he said what he was shooting. Our OP was having some issues here and I was just saying..:rolleyes:

Corran
21-Aug-2011, 08:08
The camera is being returned. The seller was also unfortunately unaware of the wrong cam being in the camera when he bought it.

Frank, thank you for your help. I appreciate your knowledge/expertise a lot on the forum, I was just a bit put off by your cavalier attitude about just using Google. I had been been trying for hours with no luck using information from various places.

Anyway, this thread can be closed as far as I am concerned.

Frank Petronio
21-Aug-2011, 10:02
Sorry, I get punchy ;-p but I tried Googling your question too and there is a mess of confusing information.

In the end, it is just a lot easier to get one with the stock lens ready to shoot than to muck around. If you want to use exotic lenses with a rangefinder, get a $$$ Technika and have the lens cam properly made. It's expensive but it's the right way to do it.

Corran
21-Aug-2011, 10:19
Exactly, that was my problem. Lots of different info.

I'm hoping to try this out with the Graphic and then if it's going well get something better. Anyway, I wasn't trying to muck around (yet!), I was just going to use the "stock" lens. The 152mm is apparently not that common but was used on occasion on the Crown with the corresponding cam...but this one has been mucked with. :(

Ivan J. Eberle
21-Aug-2011, 10:30
Get one with a 135mm Xenar and the installed cam will likely be correct! These can be perfectly fine lenses although they don't offer much excess image circle for moves.

BradS
21-Aug-2011, 10:34
Bryan,
Sorry for your difficulty and I apologize again if my tone last night came across as harsh. I really was trying to help. I agree with Frank's advice about returning the broken, messed up camera. Too many sellers have no clue.

I agree too that items sold by a seller who knows well what is offered and who has a reputation of honest, accurate descriptions are worth a premium price. Too many buyers do not understand the value added by knowledgeable and honorable sellers.

The 152mm Ektar is a lovely lens....but, you're correct. It was much less commonly found on Graphics than the 135mm Optar and 135mm Xenar - which are also both very fine optics. I actually prefer the 135mm Optar for the very fact that they are so common, generally unloved and inexpensive and yet a fantastic optic.

Ivan J. Eberle
21-Aug-2011, 11:21
135mm Wollensak-made Optars are perfectly fine lenses, as well. (I like the Wolly Raptars, optically identical and equally maligned for no good reason, but they tend to be even less expensive used.)

The Xenars were contemporaneous to the Top Mount RF Crown Specials, I think?

One benefit of a Xenar over the Wollensak-built Optars is that the lens cells will almost always be fitted to a Compur shutter. If/when the shutter croaks, the cells will fit the threads of a modern Copal shutter.

Not the case with the Graphex/Rapax ones (or the Supermatics, either). Though these shutters were probably more robust than currently-available Copals, and may be CLA'd to run consistently, they tend to run consistently slow after 50 years. New springs haven't been made for almost 40 years, nowhere to be found at this late date AFAIK.

BradS
21-Aug-2011, 12:14
Good points Ivan. Why do those old compur shutters always end up un-repairable. I shudder to think how many I've donated to the repair shop for parts.

It is ironic that the Xenar was originally a LOWER cost (and much maligned) alternative to the American made Ektar and Optar.

Leigh
21-Aug-2011, 12:20
Why do those old co[m]pur shutters always end up un-repairable.
They're not "un-repairable". It's just that most modern repairmen don't know how to work on them and don't have the factory instructions.

I still have a large stock of parts for those. They're built like battleships and seldom have real problems, other than needing a good CLA.

Granted, some parts are no longer available, but many can be fabricated if the tech knows what he's doing. Sadly most modern techs don't.

- Leigh

Frank Petronio
21-Aug-2011, 12:25
Frank Mars.hman at Camera Wiz in VA is great with these... I used to be a "German is better snob" but Rochester-made is and was world-class

BradS
21-Aug-2011, 12:42
They're not "un-repairable". It's just that most modern repairmen don't know how to work on them and don't have the factory instructions.

I still have a large stock of parts for those. They're built like battleships and seldom have real problems, other than needing a good CLA.

Granted, some parts are no longer available, but many can be fabricated if the tech knows what he's doing. Sadly most modern techs don't.

- Leigh

Thanks for your insight. Perhaps you are a better shutter repair person or have a better supply of NOS part than Carol Miller? Surely, you are not suggesting that she falls under the category of "most modern techs". I've donated a couple of old compur shutters to her that she said could not be repaired (I assume she meant that it was not feasible to repair them).

Do you offer a shutter repair CLA service? If so, what are you prices for a CLA? Where is your web site. I'd be very happy to send you some work.

Leigh
21-Aug-2011, 12:58
Hi Brad,

I don't know Carol Miller, so I can't comment one way or the other. Certainly there are proficient repair shops/individuals still in business. My comment was based on the fact that most folks who knew those shutters and how to repair them are retired or dead.

I'm retired, but not dead, at least time last I checked. :D

The main source of technicians in the camera repair and similar industries has historically been the military. They stopped teaching repair of mechanical shutters decades ago. And they no longer teach techs how to make parts. I was originally trained as a tool and die maker, so I'm quite familiar with fabrication techniques.

I no longer do repair work for others due to failing eyesight and manual dexterity problems that make it difficult to work with small parts. I'm tired of dropping little screws. I used to repair Nikons, Hasselblads, and Compur shutters.

- Leigh

Frank Petronio
21-Aug-2011, 14:28
I was on my phone... Frank Marshman's number is 540-434-8133 and he is excellent with older shutters, Graflex and Fuji medium format stuff.

tom thomas
23-Aug-2011, 15:03
Been gone a couple days but found this thread very interesting as I have a Speed 45 with top rangefinder. Luckily mine is close for my 135mmlens.

There is a Kalart Top Mount Service manual available free on the web which describes the Master Cam, it's use, etc. South Bristol has it as well as the full ops manual for the Speed/Crown's of this era.

Check
http://www.southbristolviews.com/pics/Graphic/manual-pdf/TRFService.pdf
and it will drop you right in on the adjustment procedure using a Master Cam. There is even a graphic of it showing dimensions, critical edges, etc. Apparently the cam is 1 inch long and 0.437 plus/minus 0.0001 inches high. The cam has a tolerance of 0.0001 inches when made so adjustment tolerance is also up to 0.0001 inch at infinity. Infinity in this case is defined by Graflex as 500 feet or more.


According to the manual, on the top mount model Graflex's, the Rangefinder is calibrated to Infinity first using a master cam, then the remaing adjustments are made to the lens and cam's themselves. That's why the master cam is important, or was considered so.

On Page 7, there are instructions for determining true infinity and close distances for non-standard lens and cams. Interesting.

I'm glad my rangefinder only had a mirror retaining clip loose in the rangefinder as this could get confusing for a beginner.

Tom

Tim k
23-Aug-2011, 15:26
Anyway, this thread can be closed as far as I am concerned.

Ahh, if only it was that simple...:rolleyes:

Corran
23-Aug-2011, 15:51
Check
http://www.southbristolviews.com/pics/Graphic/manual-pdf/TRFService.pdf
and it will drop you right in on the adjustment procedure using a Master Cam.

Thanks Tom for the link, I found something similar but not so detailed before. I now have TWO Graphics, one Speed and one Crown on the way so I will be on the bench tinkering with at least the side-mounted Kalart on the Speed to try to adapt it to a non-standard lens, and keeping the Crown/Top RF with 135mm Xenar only, hopefully with the right cam this time...

MikeSeb
18-Sep-2011, 18:13
My Crown's top-mounted Graflex RF has been giving me fits also. (152mm Ektar, correct cam installed, infinity stops set properly.)

The RF is off ever so slightly at all distances; obviously it looks the worst at closest range. It's a sweet Crown, and I had Fred Lustig do a CLA several years ago. I've been using it a lot more lately, with mostly Grafmatic backs attached. So I really want the RF to be in calibration. Easier said than done, it seems.

I got hold of the Crown's repair manual and it's pretty clear on how to do the adjustments --- you loosen the screw that tightens the RF arm onto the "stem" of the moveable mirror, and turn the mirror mount until the RF images coincide (looking at a target object that is also in focus on the GG, of course). Then you re-tighten the screw and Bob should be your uncle.

The niggling little thing, though, is that when you go to re-tighten that screw, its rotation on the mirror "stem" moves the mirror ever so slightly out of whack, unless you hold it with your third or fourth hand. My hands aren't that steady. Frustrating.

I finally got mine acceptably close to accurate; but it's worked its way out of adjustment AGAIN.

Any thoughts on getting, and keeping, the damn thing in calibration?

rdenney
18-Sep-2011, 21:56
Here's what I did to set the infinity stops on the 127 Optar that came with my Speed: I moved the focus rail until the top rangefinder (with the correct cam) showed an infinity target in focus. I then locked the rail down. The rail should be just a bit out from being backed all the way into the camera. If it isn't, then there's some other issue that has to be resolved. But my approach works on the assumption that the rangefinder is properly adjusted and I just need to know where to put the infinity stops.

With the rangefinder showing an infinity target in focus, I then position the lens on the rail until that same infinity target is in focus on the ground glass. I used a strong loupe to be sure (10x). Now, the lens agrees with the rangefinder at infinity. I lock down the infinity stops, and lock down the focus scale pointer.

If the other distances are not now in focus, then there's a problem with the rangefinder or the cam is not the correct one.

When I set up the added Kalart side rangefinder, I started with the focus rail reading in focus at infinity. That way, both rangefinders agree at infinity.

Everything I read in the thread did not seem to mention that the focus rail has to be positioned so that the rangefinder reads infinity. Unlike with the Kalart, I don't see where the linkage between the focus rail and the rangefinder is adjustible.

Oh--another thing. You have to check both infinity stops to make sure that the lens will focus evenly across the frame with a flat target.

Rick "for whom this is currently fresh on his mind" Denney

Corran
18-Sep-2011, 22:35
I ended up getting another Crown with a Schneider 135mm Xenar and it came calibrated and has stayed calibrated. Your problem sounds like my original problem. Are you 100% sure it's the right cam??

*And Rick is now the official expert on calibrating the RF's as far as I'm concerned...by the way Rick, which Kalart do you have, the newer or older one? I'm building yet another custom with an older Kalart that I have yet to open up and see how it works. I'm hoping it's similar to the newer model?

rdenney
19-Sep-2011, 00:21
by the way Rick, which Kalart do you have, the newer or older one? I'm building yet another custom with an older Kalart that I have yet to open up and see how it works. I'm hoping it's similar to the newer model?

I'm sure the one I'm using is Pacemaker vintage. The only difference between the Pacemaker and Anniversary vintages that I can see is the shape of the actuator arm, and the position of the flat that is filed into the input shaft. All the internal parts looks the same, except for the manner in which the lateral alignment is done. The older ones have an external screw for that adjustment, while the newer one has to be adjusted with the cover off. But I'm certainly no expert. Now that I know how they work, though, I might use them for other projects.

Rick "who has a pile o' parts of various vintages, but not sure what cameras they came from" Denney

Corran
19-Sep-2011, 22:18
Cool, thanks for the info. I ordered the lens from Poland so I'm still waiting (im)patiently to receive it :)

I bought a Schneider 12.5cm f/2. It's supposed to only cover 9cm long film but I'll be using it at portrait distances so I'm hoping to get close to filling the 4x5.

mamypoko
21-Sep-2011, 00:05
I'm also looking to make a custom cam for my Aero Ektar, bought files and all, probably a lot of elbow grease needed to get it correct.

Math
21-Sep-2011, 02:16
I'm also looking to make a custom cam for my Aero Ektar, bought files and all, probably a lot of elbow grease needed to get it correct.

Keep in mind that even if you get it matched, it will be close to impossible to use due to the very very thin depth of field!

Neal Chaves
21-Sep-2011, 12:38
"Keep in mind that even if you get it matched, it will be close to impossible to use due to the very very thin depth of field!"

A split image range finder is the most accurate way to focus a hand-held camera, hence the popularity of this design. A cam can be cut so that focus will be as accurate as observing the ground glass with a loupe, which is the way you cut the cam. It may come to just one final pass of the file at the end.

nonuniform
5-Dec-2011, 01:14
If anyone does manage to create a cam for their Aero Ektar and the Crown Graphic, I will pay you to make me one too!

Corran
5-Dec-2011, 08:43
It's much easier to do with the side-mounted Kalart RF. I've done it.