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Henry Suryo
14-Jan-2009, 12:54
Not too long ago, I acquired a Graflex 8x10 Focal Plane shutter in good working condition. I don't know how old it is, but Graflex FPS were first patented in 1902 as it says on the plate, my guess is that mine had been completely overhauled some time in the past as the curtains appear to be in good condition, springs are good and strong, and speeds seem to be fairly accurate. I'm attempting to build an 8x10 SLR around this shutter based on the Graflex Series D/Super D, and was wondering if anybody here has a technical/repair manual, showing sections, cutaways, details of the Series D/Super D? I couldn't seem to find it on graflex.org and I don't really want to disassemble my Super D to see, particularly regarding the mirror mechanism and the synchronized shutter release. I can't do without the auto-diaphragm feature of the Super D. Thanks in advance.

Walter Calahan
14-Jan-2009, 13:50
Lucky you.

There are a bunch of Graflex manuals on eBay, but don't know if eBay has exactly what you are looking for. Give it a search in the eBay Store area. I think that's where I saw the various Graflex stuff.

I only have two 5x7 Graflex cameras. No 8x10.

bbjorkum
14-Jan-2009, 14:25
Rumours say that there once existed an 8x10 Graflex SLR. You are the second I've heard of that own this curtain. You could contact Lens and repro, they might know.

Walter Calahan
14-Jan-2009, 14:50
Perhaps?

http://cgi.ebay.com/Graflex-Graphic-Focal-Plane-Photography-Book-1936_W0QQitemZ200298642024QQihZ010QQcategoryZ712QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

or

http://stores.ebay.com/manualsdotcom

Henry Suryo
14-Jan-2009, 14:51
There's a repair manual for a smaller Graflex on eBay which may contain the diagrams I need, just have to scale everything up to the 8x10 size. Thanks Walter, lucky would be to successfully this difficult project with my limited skills. Graflex did advertise an 8x10 SLR in their 1904-1905 catalog, but not sure how many were actually made if any. As far as I know, McKeown has never documented the existence of one. But Graflex did sell just the FPS as an accessory, that fits directly onto several 8x10 cameras, and I believe that this is what I have, not a salvaged part from that mythical 8x10 Graflex.

Henry Suryo
14-Jan-2009, 15:03
What I mean to say in the initial post is that I can do without the auto diaphragm feature of the Super D.

Captain_joe6
14-Jan-2009, 18:30
If I were wanting to do something like this, an idea I have toyed with, I'd do this: get a beat-to-hell 4x5 series D or B or something similar, one that will obviously never photograph again, and take it apart. Use it as a learning specimen.

David A. Goldfarb
14-Jan-2009, 18:43
When I once looked into my 5x7" Press Graflex, it looked like the mirror synch mechanism was fairly straightforward. If I recall correctly, the release button that one presses on the camera only releases the mirror (so it might be better to call it the "mirror release" rather than the "shutter release"). The mirror is under spring tension, and when the mirror flips up to its velvet padded frame, it trips a lever that releases the focal plane shutter.

Drew Bedo
15-Jan-2009, 13:08
Let us know how this project comes out, and post pictures...sounds greaqt.

bbjorkum
15-Jan-2009, 13:31
What I mean to say in the initial post is that I can do without the auto diaphragm feature of the Super D.

I own a very nice custom made auto diaphragm copal 1 size that fits my Super D, which allows me to use modern 210mm's ...

Henry Suryo
15-Jan-2009, 14:16
The project is still in its infant design phase, I'm afraid it will take me months to complete. Attached is an isometric of the shell, but the design needs to be reworked. The camera is clunky looking, doesn't look like it's easy to hand hold. Also, because of the rotating back, the viewing screen needs to be at least 10x10, which makes the shortest lens than can be used is 16.5". I'd like something shorter, I think if I use a slightly smaller mirror and place it nearer to the lens, it could still reflect without cut-off to the entire screen. Don't know yet. Then there's the issue about the synchronized mirror flip and shutter release...

Bbjorkum, I seem to recall such adapter from Lens and Repro, but for a Copal 1 size, the max aperture is probably only F5.6 for a 210mm, so I thought I'd be better off saving the money for a faster lens like a Speedic, Pentac, Heliar, or Verito. And I am partial to the look of old glass.

David A. Goldfarb
15-Jan-2009, 16:47
Well, a Graflex is clunky looking, but it's mostly a big empty box and pretty well balanced, so it's surprisingly handholdable.

EdWorkman
15-Jan-2009, 20:53
You may find some schematic help from the patents. Google Patent Search uses key words like Folmer etc. If you already have a patent number, and Google won't produce results, the USPO has a site too and it requires the patent number. IIRC , and I may not, the curtain with varied slots was invented aboout 1910 or so, and the earlier curtains consist of TWO wwith dials to adjust the slot width. If the patent thing is fruitful there are other key word, like Thornton-Pickard etc. If you haven't already tried the google thing, watch out for the descriptions that are returned from a search: They are unchecked OCR results that often make no sense.

Paul Ewins
16-Jan-2009, 02:06
It seems to me that you should be able to take a 4x5, or even 3x4 Graflex with a nonfunctioning shutter but working mirror and build an extension back for it and install the shutter in that. Then build an extension on top to reposition the ground glass.
Surely that would work?

bbjorkum
16-Jan-2009, 03:57
It seems to me that you should be able to take a 4x5, or even 3x4 Graflex with a nonfunctioning shutter but working mirror and build an extension back for it and install the shutter in that. Then build an extension on top to reposition the ground glass.
Surely that would work?

Why not just make an extension back on an already working 4x5 graflex? Does the shutter need to be close to the film?

prado333
16-Jan-2009, 04:14
is so difficult to make a 8x10 modern reflex?
a few time i wrote to Alpa , but they didn´t interested in large format.
Do you thing any manufacturer could make a slr 8x10 ?
best regards

David A. Goldfarb
16-Jan-2009, 05:50
Wisner had a modern 4x5" leaf-shutter reflex camera on his website, but I don't know that it ever came to market.

I think that wouldn't be too hard to do in 8x10", since the focal plane shutter contraption wouldn't be part of the equation. The mirror would be on a spring, and would flip up and trigger the leaf shutter by something as simple as a cable release mechanism, though I suppose an electronic shutter would be more reliable in terms of firing the shutter when the viewfinder is blacked out.

Henry Suryo
16-Jan-2009, 08:20
I'm not sure a tapering extension back would work very successfully on an 4x5 Graflex without mechanical vignetting especially when the lens is racked all the way out (close-ups). This is similar to the problem I once had with the 6x17 back designed to be used on a 4x5 graflok-style back. It might even be worse going to 8x10 as it is wider. Even if it did work limitedly, it would make the body really awkward, not very ergonomic to hold probably. The reason that handholding a Graflex 4x5 works well, as David pointed out, I believe is its box shape, held from both sides with the back resting on your belly.

A reflex system using a leaf shutter is better on a TLR than an SLR I believe. The blackout between closing the shutter after viewing, cocking the shutter, and exposure would cause a considerable delay I think. The story I had heard about the Wisner 4x5 reflex was that the mirror didn't provide a light-tight trap for the film when down (viewing position). I don't know if this is true as they never really made it to the consumer market. Anybody here know of one in existence?

bbjorkum
16-Jan-2009, 14:15
Peter Gowland made an 4x5 SLR with a mirror shutter. I'm not quite sure how it worked though, but he stated that he made it because he thought the lag on the Graflex was too severe.

David A. Goldfarb
16-Jan-2009, 15:55
If you called him, I'm sure he'd be glad to explain it in detail. He loves to talk about his cameras.

Henry Suryo
16-Jan-2009, 16:26
The Gowland SLR is indeed a uniquely ingenious approach, with the lens and mirror shutter always in a fixed relationship and the film plane and gg focusing screen moving in tandem, essentially like rear focusing. According to his description on the website, the shutter consists of 3 moving parts and speed is limited to 1/50th which is perhaps more reliable and easier to maintain than a curtain focal plane shutter. I'm not sure if the rare Arca Swiss 4x5 reflex also uses a mirror shutter as it had only one instantaneous speed (1/25th I think) and a T if I'm not mistaken. Good ideas here, perhaps I can use the rear focus and small mirror approach of the Gowland, but still use the FPS that I already have for the flexibility of a wider range of shutter speeds. I shall consult with Mr. Gowland but in the meantime, back to the drawing board...thanks everyone.

Drew Bedo
18-Jan-2009, 08:53
A lot of good thoughts here about a focal-plane shuttered 8x10 SLR...I know that this is the point of the thread.

What asbout an 8x10 TLR? Advantages are simplicity of design and construction. The disadvantages are bulk and matching optics. Remember that there are many older less well corrected lenss available today that could be used for the viewing lens.

The viewing half might not need a mirror, just strasight-through gg viewing... or a conventional 8x10 back with a right angle viewer. To reduce bulk,the viewing half might be a 4x5 or smaller size to only focus the center.

While there are disadvantages to all these suggestions, they all allow the use of the focal-plane shutter to make spontainous exposures in the 8x10 format. The question (as always) iis what is one willing to give up to accomplish that?

Henry Suryo
18-Jan-2009, 10:39
I agree Drew, a TLR would also be a more rugged design by virtue of its simplicity. I love my Rolleiflex TLR, the only medium format that I still use. And if the viewing system is a straighforward GG viewing without a mirror, a shorter lens can even be used. But, I can't imagine an 8x10 TLR would be very comfortable to use hand held, 6x6 or even 4x5 are manageable, but 8x10? A 4x5 viewing system for a 8x10 taking system would reduce the bulk, but I think I'd prefer to see the full frame, what you see is what you get. Parallax is already a potential problem inherent to a TLR design.

Drew Bedo
18-Jan-2009, 15:12
Ok...now lets go over-the-top. The 8x10 TLR would indeed be unwieldy for hand holding. It might not be possable. Now,look in an astronomy magazine for what is called a Dobsonian mounted telescope. I'll bet that something similar could support the weight of an 8x10 TLR, yet provide the mobility and flexability for practical photography about anywhere one can drive a sgtroller or wheelchair.

If one were to build a rig for short focal lengths, it would be lighter; about like two Hobos or two Fotmana (..Fotomens?); still a load though.

Paul Ewins
18-Jan-2009, 15:39
Peter Gowland made a few 8x10 TLRs for customers. In his own words " I wasn't fond of this camera; weighs about 35lbs... I never used it!" Leaving aside the weight, I think the biggest problem with a TLR would be that it would simply be too tall to hand hold successfully. By the time you have the focusing screen at a comfortable distance for viewing the viewpoint of the taking lens is going to be somewhere below waist level. A straight through approach would be even worse as you try and hold it up to eye level, but out a distance so that you can see the whole screen. Definitely not a hand-holdable proposition. In any case, if you were to build a TLR then there would be no point to the focal plane shutter.

I think an SLR would be workable, the only drawback to hand holding will be finding a way of lifting the mirror smoothly so that there is a minimum of vibration. It is going to be a fairly large chunk of glass that you are moving. Maybe some sort of counterweighting would help that.

David A. Goldfarb
19-Jan-2009, 04:54
I think an SLR would be workable, the only drawback to hand holding will be finding a way of lifting the mirror smoothly so that there is a minimum of vibration. It is going to be a fairly large chunk of glass that you are moving. Maybe some sort of counterweighting would help that.

While I do handhold my 5x7" Press Graflex and am able to make some big negs that I wouldn't be able to make any other way that way, between the mirror slap, handholding, and shutter vibration, it's hard to avoid some camera motion even at high shutter speeds (it goes up to 1/1500 sec!) without a sturdy tripod and substantial head. The mirror makes a surprisingly soft landing, but the mass of the mirror just causes the camera to jump. It doesn't stop me from shooting handheld when it makes sense to do so for reasons of content, but I don't know if there's any particularly good way of avoiding it, other than making the camera body heavier and I suppose keeping the shutter lubricated to reduce vibration.

Henry Suryo
19-Jan-2009, 06:19
Between the body mass inertia and localised nature of a focal plane shutter exposure(a slit width at a time), I do feel that my 4x5 Super D gives surprisingly good results handheld even when I thought I jarred the camera or the vibration severe. Even at it slowest setting, 1/30th. With a leaf shutter, I think I would see an overall more blurring caused by vibration at the same conditions. I'm convinced also that the mirror thump happens before and its vibration dampens to an insignificant amount by the time the curtain travels. How all this translates to the 8x10 size is hard to say obviously.

Drew Bedo
19-Jan-2009, 10:22
Keep the mass and inertia of moving parts down by splitting the mirror; Half would go up, while half would go down. While trhis would make for a more complex system, the parts would be a more managable 5x7-ish in size.

NonFiction
19-Jan-2009, 17:41
What about a manual mirror? See this Razzle project:

http://homepages.ihug.com.au/~razzle/4x5_SLR/4x5_slr.html

bbjorkum
20-Jan-2009, 00:43
Noblex once made a camera pretty much similar to that Razzle.

Henry Suryo
20-Jan-2009, 07:31
I think an SLR with a manual mirror and leaf shutter would not be very instantaneous. By the time the mirror is flipped up, shutter cocked and set to the right speed, aperture closed and set to the right stop, your subject may have moved or your camera may have moved hence the need for it to be tripod mounted.

bbjorkum
21-Jan-2009, 14:16
The Noblex 4x5 SLR was called Prestoflex. It had a behind the lens shutter called Prestor 8.

Dan Fromm
21-Jan-2009, 15:17
I think an SLR with a manual mirror and leaf shutter would not be very instantaneous. By the time the mirror is flipped up, shutter cocked and set to the right speed, aperture closed and set to the right stop, your subject may have moved or your camera may have moved hence the need for it to be tripod mounted.Henry, steal ideas from early 35 mm SLRs, from the days when makers were fumbling around learning how to stop the lens' diaphragm down just before the exposure was taken. Stopping the lens down and raising the mirror are surprising similar problems and have fairly easy solutions (cocking springs, releases) as long as instant return isn't needed. Back when, I bought a dual cable release (and spent some time adjusting it) in order to be able to use an Exakta mount lens with external diaphragm automation on a Nikkormat. Specialized lens, at the time Nikon had nothing like it.

Good luck, have fun,

Dan

Sevo
21-Jan-2009, 16:35
I think an SLR with a manual mirror and leaf shutter would not be very instantaneous. By the time the mirror is flipped up, shutter cocked and set to the right speed, aperture closed and set to the right stop, your subject may have moved or your camera may have moved hence the need for it to be tripod mounted.

That has been done successfully on hundreds of camera designs, and the shutter/aperture automation on a large format would not be significantly different from 35mm, so that should be the smallest problem.

By far the biggest delay is the mirror raise time, if you don't want to make the camera kick like a mule, nor fit it with air channels doubling its already hulking size - a 8x10 has a huge mass of mirror and quite a volume of air needing to be shifted around.

Sevo

Henry Suryo
21-Mar-2009, 14:07
Well, what have I done here instead? Somewhere I got sidetracked and embarked on a different project using the focal plane shutter. I would still like to pursue the SLR project in the future but will be researching and tweaking the design ideas for now. The focal plane shutter can be detached and shared between the two cameras.

Introducing...the Perigraphe Extreme Wide Angle camera...

This camera is a revised attempt of an earlier idea, built from parts mainly the 8x10 inch focal plane shutter and a newly acquired, post-war version of the SOM Berthiot Paris Perigraphe 120mm F14. From what I gathered, the lens covers north of 105 degrees and offers a bit of movements on the 8x10. This will be kind of like my "poor man's Hypergon" camera, though I believe the anastigmat design is derived either from the Dagor (3+3) or Protar V (2+2). The camera can be used handheld but the lens is a bit dim at F14, so this will probably be limited to a bright day on 400 speed film. The focal plane shutter speeds range from 1/1000 to 1/10, and T. Not sure I will ever get to use the 1/1000th of a second with a lens this slow, but it's nice to know that the camera has that motion freezing capability should the light allow it. For most of the time, I suspect tripod use, setting it on the ground or a pedestal, shooting architecture and urban landscape will be its main domain. I'm yet to test the camera with film, but looking at the ground glass image with the maximum shift (2 inches), I can see that the lens covers the corners decently even wide open although there is significant fall-off. Having a soft spot for older lenses, the image quality is immediately likable and the view is sensationally wide with considerable depth and perspective. Depending on which direction the movement is needed, and either in horizontal or vertical orientation, the square camera body can be detached and rotated then shifted as required. In other words, 2 inches of vertical rise/fall and 1/2" lateral shift or 2 inches of lateral shift and 1/2" of vertical rise/fall. Two tripod holes are provided for this purpose. When the back is used with the sliding board inserts for 4x10 or 5x8 split-images on one 8x10 sheet of film, the lens can be centered on axis and the lensboard can be rotated 90 degrees to give additional 1/2 vertical rise/fall.

Anyway, hope this isn't too much of a digression to the original thread, I didn't know whether to post it under "Show your Camera" or Show your Homemade Cameras" threads.

jb7
21-Mar-2009, 14:45
Looks great Henry-
Is this the Ansco back we talked about a while ago?
looks like you put it to good use-

The camera looks very purposeful-
I'll be having a close look; a SWA 8x10 is on the agenda for me too at some point-

very good-

joseph

Henry Suryo
22-Mar-2009, 09:03
Joseph, thanks for your kind words. Yes, the 8x10 back was the one I had offered to sell. Most of the hardware you see on the camera actually came from an Agfa camera.

I've never really used anything shorter than a 6.5" lens on the 8x10 before, and noticed that special care must be taken to level the camera and compose so as to minimize the elongated distortion and convergence especially along the periphery. That said, when properly executed, I think there's great potential for creating really dramatic pictures using such a wide angle lens and I'm excited to explore the possibilities.

Good luck in your next camera building project, I think your Arca 8x10 is very nicely done, I'm confident that your 8x10 SWA camera will be a success as well! My only suggestion since you shoot a lot of architecture too is to have, as a minimum, the capability for rise and fall, this is really useful when you need to reduce the amount of foreground or sky (of which you will get a lot) especially when you need to have the camera leveled to keep the verticals vertical.

Drew Bedo
22-Mar-2009, 09:23
I think your 810 SWA looks great! The 1/1000th and swa would be usefum in aerialphotography. Does the cameras have any focus travel?

But back to the SLR idea...Wasent the first Polaroid SX-70 desigh an slr? The lilm plane was horisontal at the bottom of the camera...could some variation of this desigh be workable?

Henry Suryo
22-Mar-2009, 09:57
Thanks Drew. I'm impressed with the great depth of field I'm getting even at F14, so I won't hesitate to use the camera wide open. Perhaps with 400 speed film and a very bright sunny day, 1/1000th of a second is not so far-fetched at F14. The lens is fixed, adjusted using thin shims to find the best compromise in focus (hyperfocal) and I believe I can get somewhere between 10 ft to infinity in decent focus at F14.

I suppose if needed, some adjustment is possible just by turning the lens on the mounting flange thread. The focus travel is minimal at this length and a few turns would probably achieve the adjustment needed while leaving enough threads still for the lens to hang on securely. But I don't suspect I will to do this often if at all, many of the extreme wide angle cameras like the Hobo or custom ones with a Hypergon or Protar V are used successfully with a fixed focus.

Thanks for the SX-70 tip, I never realised that these were SLRs being so compact and foldable. I will have to look into this further, imagine having a 8x10 SLR that can fold tightly like that.

Henry Suryo
22-Mar-2009, 10:26
Just as a curiosity, I plugged in the numbers into a hyperfocal distance calculator and found it fairly close with my less than technical, eyeballing method for finding the best focus: for a generally-accepted circle of confusion of 0.2mm for the 8x10 film, at F14, the hyperfocal distance is about 17.6 ft and anything between the near focus of 8.78 ft and infinity is within the depth of field range of acceptable sharpness.