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View Full Version : How to make a thinner back for an Ebony 45S?



john wilton
6-Oct-2012, 18:45
I'm trying to figure out how to get all the rise the 72mm Super-Angulon XL is capable of on my Ebony 45S. Although there is no problem with infinity focus when the lens is more or less centered, the top of the back of the lens fouls the top front of the back frame beyond an inch or so of rise, i.e. long before the lens runs out of coverage. (There is of course a layer of bag bellows between the lens and the back frame). 2.4mm more backward travel in the extended rise position would solve the problem. One solution would be to have someone (Hiromi or Richard Ritter?) carve an indent into the top front of the back box (ugly). Or somehow make a back that moves the ground glass closer to the camera--not easy as it is only 5mm away now.

Obviously a recessed lens board is not the solution; the back of the lens needs to be in the same spot regardless of where the camera front is.

Has anyone else run into this problem, and how have they solved it?

ic-racer
7-Oct-2012, 07:05
It looks like it is fouling on the bellows. How about having a proper bag bellows made.

Daniel Stone
7-Oct-2012, 08:28
Get a bag bellows made

BradS
7-Oct-2012, 14:00
is the lens mounted in a lens board with the hole offset below the center line? Would it help to have the lens mounted in a lens board with the hole drilled in the center - or even custom drilled a little above center?

Jeff Keller
7-Oct-2012, 16:25
Isn't the back of an Ebony SW45 thinner? If you could either get the back of a SW45 or have yours modified it might give you what you want.

http://www.ebonycamera.com/cam/main.SW45.html

Jeff Keller

john wilton
7-Oct-2012, 17:10
I guess I did not express myself very well. The top of the box, NOT THE BELLOWS, prevents infinity focus when the lens is in a high rise position. As I said there is just one irreducible thin layer of bag bellows between the lens and the box. Even if the bellows were removed the back of the lens would still hit the box as it approached infinity focus. The front of the ebony 45S bellows IS a bag bellows. Bag bellows has nothing to do with it, nor does the position of the hole on the lens board.

Jeff, it does look as if I'll have to mod my camera. Problem with the SW45, which certainly looks as if it would work (aside from cost), is that the much greater max extension of the 45S makes it a more universal camera.

I had hoped someone might have experience they could share with making an ultra-thin back and thus perhaps avoid surgery on the camera. A friend has suggested modding a plain flat-plate Arca back, but I don't have one to look at to evaluate the feasibility.

taulen
7-Oct-2012, 18:14
Find a 75mm lens ? Wouldnt that solve the problem ? Not the answer you're looking for, but that will give you the 3mm's, and you wont really notice a difference with 72 vs 75mm...

Frank Petronio
7-Oct-2012, 18:19
$250 gets you a Sinar F, cheaper than anything else.

Jeff Keller
7-Oct-2012, 18:42
John, it might be worth a try to see if Ebony Camera would replace your wooden back frame with one from an SW45. Replacing your 45S frame with a SW45 frame might give you the best of both cameras. Other than removing then reattaching the bellows, changing the back frame is probably easy.

The bellows and the rack are longer on the 45S giving the wider bellows range. The 45S back frame is probably deeper so that the longer bellows will fit completely inside when closed up. The titanium uprights of your 45S would probably work with the wooden back frame from the SW45. You would likely loose a little on the max extention ... the difference in the depth of the backs is all. Your bellows would probably be slightly exposed when your camera was completely closed up.

With the shorter min extention, your camera would be somewhat more useful with a roll film back.

Jeff Keller

Steve Barber
7-Oct-2012, 21:36
I do not have any experience with your model, but I have the same problem with the SV45U2 (rated for 42mm max rise) and the WIDE45 (60mm). Ebony does not show the inside dimensions of the rear standard frames for their cameras. My SV45 is 159 by 159mm and the WIDE45 measures 149x149mm. Neither will allow taking advantage of the full capability of either the 72 S-A XL or the 90mm Super-Angulon XL lenses. Both will give their rated maximum with the 90mm, but the SX45U2, with the wide angle bellows, will only allow about 37mm in rise with the 72mm and the WIDE45, with its comparatively shorter and more flexible bellows will only allow about 32mm in rise with the 72mm lens due to its smaller frame.

In comparison, a Wisner 4x5 Technical Field camera with its larger rear standard frame, 187x187mm inside dimensions, will accommodate either of these lenses, with full movements and its seems to me, from what I can see, the larger frame is the solution. Just modifying your camera to allow the 72mm lensís rear element to clear the top of the frame and obtain the full amount of rise your 45S is rated for, 50mm, will, I think, still leave the rear of the lens being partially covered by the cameraís frame and bellows.

C. D. Keth
7-Oct-2012, 21:42
Isn't this a super simple job for a router? I think you're overthinking it.

john wilton
8-Oct-2012, 09:53
Steve, a larger frame is a solution; I can use the 72XL on a Shen-hao non-folding 5x7 with reduction back without problems. But the setup is then much bigger and not practical for my needs; and the Ebony non-folder is so much easier to use. I don't think obscuring the top part of the back of the lens is a problem, in fact it's a good thing as the rays passing through that area are not headed towards the film and would otherwise bounce around inside the camera.

Christopher, I'm not sure if routing would be so simple: presumably the camera have to be dismantled and the non-interchangeable bellows removed, not entirely trivial. I've read that ebony wood is very difficult to work with.

rdenney
8-Oct-2012, 10:09
People are considering carving up a multi-thousand-dollar art-piece of a camera to accommodate the sort of rise for which any decent monorail, which can be had for pennies on the dollar, has already been designed?

I don't get it. For the few pictures that need this treatment, just use a camera purpose-built for that application.

Rick "with Frank, as usual, on this topic" Denney

BradS
8-Oct-2012, 10:48
People are considering carving up a multi-thousand-dollar art-piece of a camera to accommodate the sort of rise for which any decent monorail, which can be had for pennies on the dollar, has already been designed?

I don't get it. For the few pictures that need this treatment, just use a camera purpose-built for that application.

Rick "with Frank, as usual, on this topic" Denney

everybody's thinking....thanks for saying it. Seems crazy to me to hack up an Ebony - for any reason - but especially, for a reason so easily addressed by a cheap alternative.

Frank Petronio
8-Oct-2012, 11:21
But that 72XL is such a compact backpack-friendly lens ;-) Every gram matters! Might as well drill some lightening holes in the camera while you've got it in the shop.

Steve Barber
9-Oct-2012, 20:50
What is so difficult to understand about someone wanting to be able to use a lens to its full capability on a camera that, otherwise, meets all his needs and is rated for the rise desired, but cannot, in fact, achieve it with this lens?

81791

This picture was taken with the 90mm S-A XL and is an example of why I acquired the 72mm version. Too many times, with the 90mm, I end up with my back to the wall or standing on the edge of a cliff, as here, and it just will not get everything I want. So, when you pay the extra cost and put up with the extra weight and bulk, it is for a reason. I do not know and I am not going to drive back down there just to find out, but I have an idea that most of the rise the 72mm Super-Angulon XL is capable of would be useful for this shot and I would like to be able to obtain it without having to lug another camera around.

And, give us a little credit. I have a monorail or two or, maybe, more and if I think lugging one of those around on a trip will be worth the space and effort, I can do that. But, turning your own logic around, that is a lot of bulk and inconvenience for the few shots it might be needed for. Particularly where with, perhaps, some relatively minor modification, the camera I prefer to use could be made to completely eliminate any need at all for dragging a monorail around.

Cletus
10-Oct-2012, 04:21
Second the suggestion of getting a 75mm lens. You could probably get that and something else for the price you'd fetch for the 72XL. I'd challenge anyone to spot those 3mm difference in practice. And how much movement do you really need with a lens that wide near infinity? And wouldn't tilting the bed up, ever so slightly, to rid yourself of the clearance issue, be at all noticeable near infinity?

I'm sure all these things would be greatly exaggerrated if you were shooting at macro range. But then your back clearance problem disappears anyway. Am I way off on this?

Steve Barber
10-Oct-2012, 05:21
Second the suggestion of getting a 75mm lens. You could probably get that and something else for the price you'd fetch for the 72XL. I'd challenge anyone to spot those 3mm difference in practice. And how much movement do you really need with a lens that wide near infinity? And wouldn't tilting the bed up, ever so slightly, to rid yourself of the clearance issue, be at all noticeable near infinity?

I'm sure all these things would be greatly exaggerrated if you were shooting at macro range. But then your back clearance problem disappears anyway. Am I way off on this?

Sure, you can use a different lens, but then you lose the capability of the 72mm S-A XL, almost a third of its total or about 15mm in rise, not 3mm. And, yes, as I tried to illustrate, with the example above, you will miss it. Last, tilting the bed up works with the 90mm lens, because its rear element is far enough out to clear the rear standard frame. With the 72mm, tilting the bed does nothing to solve the problem of the rear element hitting the underneath of the frame, when the camera is focused at infinity, and the total rise available remains unchanged, tilted or not.

rdenney
10-Oct-2012, 05:29
Why don't you grind off the interfering portion of the lens barrel?

Rick "wondering if that will seem offensive" Denney

Steve Barber
10-Oct-2012, 05:38
Why don't you grind off the interfering portion of the lens barrel?

Rick "wondering if that will seem offensive" Denney

Not so much "offensive" as just "snide"

rdenney
10-Oct-2012, 08:47
Not so much "offensive" as just "snide"

Guilty as charged.

But it's not completely without a serious point. Even a 72mm SA XL is less expensive than an Ebony 45S. In fact, the new lens usually sells for less than a used 45S, and a used lens might be half a used camera. If it seems snide to suggest grinding away the lens barrel, then why would it seem snide to think it nuts to grind away the camera body?

I ground away the rear barrel of a Schneider Curtagon so that it would fit on my Canon 5D (with adapter) without mirror interference. Of course, I was grinding on a lens I paid $50 for to avoid damaging a $2000 camera, so maybe that's an extreme example. :)

Rick "not above grinding, but usually choosing stuff with throwaway value before attempting it" Denney

Steve Barber
10-Oct-2012, 10:03
If you will look, you will see that I have not suggested or agreed that modifying the 45S by removing part of the top of the rear standard frame was a workable solution. What I think would solve the problem is a bigger frame. As I said, I do not have a 45S and I do not have access to any of the Ebony camera specifications for the inside dimensions of the rear standard frames of any of their cameras. If those were available, it might be possible to find another model, one similar to the 45S, that could be bought in standard form and solve the problem. If it were me, I would either find another model, buy it and sell the 45S or contact Ebony and see how much it would cost to modify the 45S rear frame to the height needed to clear the rear lens element and gain the full 50mm of front rise that the camera is rated for. My sense is that I would, probably, just get another camera and sell the 45S.

As to my cameras, I have absolutely no intention of trying to modify the SV45U2 in any way and I would not recommend that to anyone else. I determined, some time ago, that I wanted another camera specifically for the shorter focal length lenses. That was my reason for getting the WIDE45 and I am very happy with it. Also, I will say that I find the WIDE45 a lot more convenient and useful than hauling a monorail around.

john wilton
10-Oct-2012, 18:38
There are reasons why I want to stick with the 45S. It is light, very very fast, versatile and a joy to use. I lift it out of a small (25 litre) rucksack-type backpack with lens mounted, drop on tripod ready to frame and shoot.

Yes, I know about monorails. Started out with a sinar f and have no intention of retracing my steps. Other choices involve other compromises: bigger; less bellows extension for other lenses and so on. An SW45 with its narrower frame would work with the XL, but I wouldn't buy it even if one were available on the forum right now at a good price because of its limited bellows extension; solving my immediate problem but creating another.

Going into the field with two cameras is out of the question.

I really don't think Hiromi will be upset when his camera is modded to accommodate an incredible lens that could not have been anticipated and didn't exist when the camera was designed, mine was made in the mid 80s. He says on the Ebony website that he hopes his cameras will acquire the scars of hard usage, or words to that effect. My camera was certainly not pristine when I acquired it. People have been modifying gear to get a job done since time immemorial, and I think that is a beautiful thing.

Re 75mm (and 65mm), I have them, that's why I bought an XL. I would not have spent the large sum needed for a 72XL plus center filter, comparable to what I paid for the camera, if the 75/65 coverage were in the same ballpark.

In any case the die is cast, my camera is en route to Richard.

Ian David
10-Oct-2012, 21:49
People are considering carving up a multi-thousand-dollar art-piece of a camera to accommodate the sort of rise for which any decent monorail, which can be had for pennies on the dollar, has already been designed?

I don't get it...

This is an interesting variation on the usual approach to Ebony-ownership, Rick.

Generally such people are admonished for forgetting the rule that "a camera is just a tool" and consequently spending more than is appropriate on their hardware. Now I am seeing an admonition for forgetting the rule that "an Ebony is not a tool". Poor John is in a tough position...

Perhaps John regards his Ebony as a beautiful camera that meets almost all of his LF needs, but still a tool. If it can be modified in a sensitive way that allows him to improve its functionality in some useful way, without destroying what drew him to the camera in the first place, that seems like a worthwhile course of action to at least consider, no?

John, I hope you'll keep us posted on what Richard comes up with. I would be interested to see the solution.

Ian

rdenney
10-Oct-2012, 22:16
This is an interesting variation on the usual approach to Ebony-ownership, Rick.

Generally such people are admonished for forgetting the rule that "a camera is just a tool" and consequently spending more than is appropriate on their hardware. Now I am seeing an admonition for forgetting the rule that "an Ebony is not a tool". Poor John is in a tough position...

Perhaps John regards his Ebony as a beautiful camera that meets almost all of his LF needs, but still a tool. If it can be modified in a sensitive way that allows him to improve its functionality in some useful way, without destroying what drew him to the camera in the first place, that seems like a worthwhile course of action to at least consider, no?

John, I hope you'll keep us posted on what Richard comes up with. I would be interested to see the solution.

Ian

Oh, hell. It's his camera--he can do what he wants with it. I'm glad he's sending it to a real craftsman to make the modification--I'm sure that will turn out just as he hopes.

But if it's all just tools, then why did people think I was being stupid for suggesting carving away the lens barrel rather than the (more expensive) camera?

When I grind on a mere tool to make it into a different tool, I tend to choose an inexpensive tool in the first place, in case my grinding goes astray. I've customized lots of tools in my life, but never the high-end examples.

Rick "who'll grind a Craftsman wrench but not a Snap-On wrench" Denney

George Hart
10-Oct-2012, 23:58
Goodness me. I have the this camera and I immediately recognized the problem that John is having with the 72 XL lens. On thinking through the options before buying the 45S it was apparent that a 55 mm Apo-Grandagon lens would not out-rise the top of the rear standard of the 23S (I shoot mainly 6x9 with this camera), so I went for the bigger camera. I'm glad I did for other reasons too.

I agree with others here that it doesn't seem right to mutilate a very fine camera. I have checked how much rise I can get with my 75 mm Grandagon-N focussed at infinity (the FFD is almost exactly the same as the SA XL 72 mm), and I can easily get the lens above the top of the rear standard. However the 72 mm XL lens is almost 6 mm longer, so I guess that ~3 mm would need to come off the top front of the rear standard box if that's what you wanted to do.

As stated above the most elegant and doubtless also costly option would be to get Hiromi to replace the rear standard, so making the equivalent of their SW45SII or III cameras. You would lose ~10 mm of total extension by so doing, which may of course be important to you.

I guess that if Richard shaves off part of the top panel, you may also lose the "jewel box" spirit level device. Whatever, it hurts me to look at my 45S and think of hacking off part of the top of this instrument.

I hope that your final solution works…

and doesn't look too bad…

Steve Barber
11-Oct-2012, 02:19
Oh, hell. It's his camera--he can do what he wants with it. I'm glad he's sending it to a real craftsman to make the modification--I'm sure that will turn out just as he hopes.

But if it's all just tools, then why did people think I was being stupid for suggesting carving away the lens barrel rather than the (more expensive) camera?

When I grind on a mere tool to make it into a different tool, I tend to choose an inexpensive tool in the first place, in case my grinding goes astray. I've customized lots of tools in my life, but never the high-end examples.

Rick "who'll grind a Craftsman wrench but not a Snap-On wrench" Denney


You asked, so I will answer.

The reason is that there is not enough lens barrel to take care of the problem by removing it. For the 72mm lens, you would need to remove a minimum of about 12.5mm of material and 15mm would be better. Unfortunately, after grinding away about 10mm of lens barrel, you would be beyond the barrel and into the lens, itself. That is for reducing the outside diameter of the rear element. As to shortening the rear element, there is even less material available.

The rear element of the 90mm lens is even larger, but the rearmost portion of the 90mm lens's rear element housing is threaded and can be removed. This is necessary to do, anyway, because you cannot get the rear element of the 90mm S-A XL lens through the front standard without removing the threaded rear portion and reducing the rear element diameter enough to allow it to pass through.

So, for the 72mm lens, there is not enough material that can be removed and with the 90mm lens, where there is enough material that grinding it away would be useful, Schneider has already made its removal possible, in a more elegant way.

Steve Barber
11-Oct-2012, 02:27
In any case the die is cast, my camera is en route to Richard.


Well, since you are breaking trail, I would very much appreciate knowing how it turns out.

BradS
11-Oct-2012, 11:13
.... why did people think I was being stupid for suggesting carving away the lens barrel rather than the (more expensive) camera?
Rick "who'll grind a Craftsman wrench but not a Snap-On wrench" Denney

from my perspective, there was just one person...all the rest of us probably thought it an excellent counter example.

I think the Op should just get out a set of exacto knives and start hacking away...or better still, just go after that damned "it's just a tool" with a skill saw.