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  1. #31
    TheToadMen's Avatar
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    Hi John,
    It will probably something like that. The only thing is I don't have a 2nd back with a ground glass. I was thinking of getting a cheap ground glass and making a simple wooden frame for it with the dimensions of a film holder.
    I was wondering: over here they sell photo frames with a mate type glass. Would this suffice for a very simple ground glass?
    Or has anyone a spare one to donate to this experiment? ;-)

  2. #32

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    Very easy to do a passable ground glass. Instructions are elsewhere on this site. I used rock polishing grit since that's what I had handy.
    "Far more critical than what we know or do not know is what we do not want to know." - Eric Hoffer

  3. #33

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    There’s a good article here on making a ground glass.

    http://www.apug.org/forums/forum216/...us-screen.html

  4. #34
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    Hi Bert and All,

    I'm also planning to construct a simple fixed focus camera for 5x7 paper negatives. I can see that ground glass isn't too hard, but I wonder if I can use a piece of vellum or something like that just for one time setting the focus? My idea was to try to set the focus just before I build the back onto the camera ( mine will not take film holders, but will use a clever "storage" compartment that I saw Joe use on F295. I've picked out a lens that might work, but perhaps something simple like this could also be used to check coverage. Anyhow, I'm going to give that a try. Mine will be extremely simple.

    P.S. Bert, I was born the same year your Schneider-Kreuznach Super-Angulon was made!

  5. #35
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    Quote Originally Posted by Sirius Glass View Post
    What you want is called a 4"x5" Pacemaker Speed Graphic.
    Hi Sirius,
    Thanks for the tip. I looked it up and it is a nice camera. See: http://www.graflex.org/speed-graphic/pacemaker-speed-graphic.html.
    I would like to use one of these. It was a journalist point-and-shoot camera.
    My project will be even simpeler, though: no bellows, no raise and fall.

    BTW: I liked this rermark on Wikipedia:
    The Speed Graphic was a slow camera. Each exposure required the photographer to change the film sheet, focus the camera, cock the shutter, and press the shutter. Faster shooting can be achieved with the Grafmatic film holder, which is a six sheet film "changer" that holds each sheet in a septum.[2] Photographers had to be conservative and anticipate when the action was about to take place to take the right picture. The cry, "Just one more!" if a shot was missed was common. President Harry Truman introduced the White House photographers as the "Just One More Club".
    (Source: http://en.wikipedia.org/wiki/Speed_Graphic)
    That's me: just one more camera, just one more project, just one more alternate photo technique, just one more ...

  6. #36

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    I have built something similar out of 1/8in. hobby plywood. Next time I'd use 3/16in. My lens is a Kodak 130mm f7.7 with front cell focusing to 6 ft. It came from an old Kodak folder gifted to me that was in really bad shape, broken strut, lots of holes in the bellows. The lens was clean and the shutter worked so I decided to use the lens. I determined the distance from the film plane by attaching it to a bellows with tape. I measured the bellows extension in mm with the lens moved to infinity. I added that value to the flange distance of the camera body and that was the distance to the film plane at infinity. I cut the wood as close as I could, very slightly shallow, and then brought the final assembly to infinity with paper shims behind the lens. I used RC glossy paper in the film holders just to test if I'd got it right. Now a lot of these old 2.5 X 4.5 inch format Kodak folders moved the entire front standard to focus, but some of them had front cell focusing. If looking for one to salvage the lens then check carefully how the focusing works.

  7. #37
    jnanian's Avatar
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    you CAN use waxed paper instead of ground glass
    but glass won't rip and is well ... solid

    btw toadman
    you can make / use a box camera
    they make / made them for 4x5 ...
    all you would need to do is put a lensboard on it
    to recess it to the sweet spot of your lens.

    have fun !
    john

  8. #38
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    Suggestions:
    If you are going to use positive paper, I would reccomend going straight to a 5x7 with your super angulon 121. The 4x5 positive is a little small for display. The 5x7 is very nice. Also, your 121 super angulon will easily cover 5x7. And you will get much better depth of field using it on 5x7.
    Go not to the elves for counsel, for they will say both yes and no.

  9. #39
    Joe VanCleave's Avatar
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    Quote Originally Posted by NedL View Post
    Hi Bert and All,

    I'm also planning to construct a simple fixed focus camera for 5x7 paper negatives. I can see that ground glass isn't too hard, but I wonder if I can use a piece of vellum or something like that just for one time setting the focus? My idea was to try to set the focus just before I build the back onto the camera ( mine will not take film holders, but will use a clever "storage" compartment that I saw Joe use on F295. I've picked out a lens that might work, but perhaps something simple like this could also be used to check coverage. Anyhow, I'm going to give that a try. Mine will be extremely simple.

    P.S. Bert, I was born the same year your Schneider-Kreuznach Super-Angulon was made!
    Hi Ned, I'm glad to see that someone remembers my old foam core sliding box binocular lens camera. For something like a hyper focal camera, just a bit of sliding action of the rear box into the front can ensure accurate focus from a few feet to infinity, without needing much bellows draw, especially when the aperture is already stopped down to a reasonably small aperture. This means you can build a shallow sliding box camera without an excessively long base board, affording (relatively) compact size while still being able to focus the camera.

    My bino lens camera used a 150mm f.l. lens stopped down to around a 3mm aperture, giving an f/50 focal ratio for good DOF and also correcting many of the off-axis aberrations of such lenses seen when operated wide open, so the pictures were surprisingly sharp, corner to corner.

    Another benefit of such a small aperture was slow enough shutter speeds as to dispense with a mechanical shutter for paper negatives and instead using a lens cap shutter hand operated.

    For a ground glass, vellum can work fine in terms of seeing a projected image, though the flexibility of the material means the screen can flex and cause focus errors, especially when the box is drawn in or out and the air pressure pulls or pushes on the screen. Better to use a thin, stiff piece of clear acrylic plastic, from the hardware store, and grind one side down with very fine emory paper in a random orbital sander. Another thing that works even better are these large, sheet sized plastic fresnel magnifiers, available at Staples office supply store in 8.5 x11inch size, you grind down the flat, non-ridged side the same way, with that side facing the lens and the fresnel facing toward the rear, and you have a ground glass with fresnel built in.

    The way I manage the ground glass screen with film holders is to make a frame for the ground glass that positions it at the same distance as the film would be in a film holder, the frame being very similar in size. You compose and focus on the screen, then remove it and install the film holder. The rear surface of the box camera is an opening where you can see the glass to compose and focus, while still having enough of a frame to hold the film holder and provide a light tight seal.

    You don't even have to use commercial film holders, just make one out of a 4 layer sandwich of thin plywood or even foam core board, with the dark slide not able to be completely removed, like a plate holder uses. Vey simple, doesn't require the complex double felt light trap of the commercial holders.

    You'd be surprised at how nice of an image can result from such seemingly primitive designs, which is part of their charm.

    ~Joe

    PS: use a removable aperture stop in front of the lens, affording a bright image to compose and focus, then stop down to take the picture. If you make the sliding box (or bellows) long enough to afford close up focusing, measure your aperture stops diameter in millimeters, then use a tape measure to measure the distance from lens to film when focused close up, divide the one into the other, and you have your working aperture already compensated for bellows extension. One of my cameras has such a distance scale affixed to the base board of the camera, where I can quickly reference the focal length and divide it by the aperture diameter to quickly determine focal ratio in a snap.
    Last edited by Joe VanCleave; 01-14-2013 at 11:32 PM. Click to view previous post history.

  10. #40
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    Hi Joe,

    Wow. Thanks for taking the time to type in so much great information!

    Yes I pored over many of your posts over on F295, they form an impressive amount of practical information and advice! The foam core sliding box camera really caught my eye and is what eventually made me decide to start down the "camera making" path!

    This all started for me when I found my wife's grandmother's old Kodak 1A in our garage. I knew people used paper negatives in pinhole cameras, so I thought to myself, why not cut a paper negative to fit right into this camera. At that time, I didn't know that lots of other people have already gone down the path of paper negatives in lensed cameras. Some searching around on the internet led me to F295, and from there to reading probably 90% of your posts in the forums! Fortunately this was before the site switchover, so the links in your posts still worked.

    It was a huge advantage to read about pre-flashing and other tips and tricks before I ever even started. Thank you for taking the time and effort of documenting and sharing so many of your experiments and explorations over the years. I started having fun results almost immediately. I really like paper negatives for themselves and not just as a stepping stone to using film.

    I'm going to start with something very very simple, and then progress through your many good suggestions. One of the big attractions of your original foam core camera was the simplicity of the back. The little compartment to store paper will make it quick to swap paper ( the magnets were extremely clever ). I always have trouble in my changing bag fussing with the unexposed paper in one envelope and trying to open up whatever camera I'm using and get swapped without scratching or mixing up the exposed and unexposed sheets. Your design is made for easy changing. That means I can "focus" on the front of the camera and how the aperture stops will work and how the "lensboard" will work. I want to be able to swap lens and pinhole, and I want to make the front interchangeable so that I can increase the focal length without having to rebuild the back of the camera. The lens I decided to use has scale focus, so I think I can get close and then adjust for hyperfocal with that. Also, I think I mentioned in another thread, it projects a bright image onto the interior surface of the back of the box. I think I'll be able to set the focus point quite well by looking at that. It's going to be fun!

    Definitely simple steps first before I start trying to do things like making film holders or a view screen!

    Thanks again, I'm really happy to hear from you here! This thread is bookmarked for future reference!

    Ned

    Edit: P.S. Your PS is very clever and makes perfect sense. When I get to a focusing camera, that is a great approach. There is also something "basic" about using interchangeable known apertures and measuring the focal length to compute f-value. Very nice!
    Last edited by NedL; 01-15-2013 at 02:19 PM. Click to view previous post history.

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