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  1. #11

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    http://www.sonotube.com/

    Made out of cardboard, so you can paint it black inside. Diameters up to several feet, though 14 inches might be hard to find, I know you can get larger though. Nice thing is you should be able to buy it in 3 to 6 foot lengths and longer.

    Now my question would be, wouldn't a large bag bellows work better and be lighter? You could make a frame out of 1/4 inch wooden dowels to help hold the bag so that it doesn't droop into the frame. Seems like this would have much less impact on your tripod and head than the Sonotube or PVC. And it's probably easier to make light tight and non reflective inside.

    Just a few thoughts from someone who has never tried to build anything like this, so they might be worthless ideas.

  2. #12
    Joe VanCleave's Avatar
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    Black Foamcore Sliding Box

    If budget were your main concern, and wanted to tackle the problem with a DIY approach, you may want to look to camera designs from the formative years of photography, specifically look at the George Eastman online museum. Here you will find lots of good ideas you could borrow, among the easiest being the nested, sliding box design.

    I built such a camera from black foamcore, including my own version of a sheet film holder, similar to that illustrated in the book "Primitive Photography". I used a removable view screen frame, built to the same thickness as the sheet film holder, with a sheet of translucent plastic at the same location as the film plane would be in the holder.

    I use an objective lens cell from a pair of 7x50mm binoculars for the camera lens; my lens will cover 5"x8" format fine with no movements. I use the lens wide open (at F3) for focus and composition, then stop down to around F50 with a simple black disc, with central aperture, placed over the front lens.

    For the shutter, I happen to be using paper negatives or APHS ortho lith film, which has a 'speed' of around 5, so a simple lens cap shutter, timed manually, works fine. For faster film, a mechanical shutter would have to be used.

    For your application with macro photography, just ensure that the nesting boxes will telescope out to the proper focal length with adequate overlap to ensure good mechanical stability. Of course, most nested box designs from the 19th century use a baseplate, with the 'fixed' half of the box permanently attached to the plate, and the moveable half of the box sliding in and out on grooves; such a design can be very stable.

    Good luck and keep us posted on your progress.

    Edit: For a more permanent material than foamcore board, you may want to consider multi-laminate model aircraft plywood. Using two layers of such plywood, with the sizes of both layers staggered at the edges of the panels, you can get a rabbited joint that's a very good assembly method in terms of both strength and light-tightness, without the need for fancy router tools.

    Also, I'm assuming for macro-photography, you may be wanting a rather wide aperture so as to isolate your subject with a somewhat narrow DOF; in which case the resulting shutter speed will definitely necessitate the use of a mechanical shutter, even for slow ortho media such as what I use.

    ~Joe
    Last edited by Joe VanCleave; 04-21-2007 at 01:05 PM. Click to view previous post history.

  3. #13

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    BE CAREFUL with the model plywood! It is NOT a light proof material!!!!! Even two layers of 1/16 inch think plywood transmit light far better than you want! I found this out first hand when making my pinhole camera. All you need to do is hold a flashlight behind the plywood and look at the orange glow coming out the other side. You need about 4 coats of heavy black paint to eliminate the light leaks, or line the inside with black felt or other light proof material.

    Also, do not use the urethane wood glues! They expand to fill the cracks in the wood, and penetrate down into the grain. This glue also conducts light very well, and doesn't take the type of paint that I used very well. The glue I used was Gorilla Glue brand, but Elmers and several companies offer the same thing. Gap filling Cyano-Acrylate glue might be better (untried) and should speed up the construction process.

  4. #14

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    Thanks for all the useful replies!

    I may opt for a sliding box design of some kind, just a huge bag bellows of some kind sounds better (lighter) but I do need at least front tilt. At 2x depth of field even at f45 would be very small so I need to use front tilt to use any DOF I have for my advantage.

    Thanks again. Will keept you posted.

  5. #15

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    Um, Philip, at 2:1 nominal f/45 turns into effective f/135. For contact printing, you'll want to think about DoF for a CoC of perhaps 0.1 mm, that works out to around 7 mm. And at f/135 effective 10 lp/mm is about what diffraction will allow you. So maybe you'll be able to shoot at that small an aperture without losing anything to diffraction if you contact print. If you want to enlarge, you'll have to shoot at a larger aperture.

    Why tilt the lensboard when you can reorient the entire camera or the subject? The only reason to use tilt is that the film plane can't be made parallel to the desired plane of best focus.

  6. #16

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    So are you saying that we are almost in the realm of a pinhole camera?

  7. #17

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    Philip,

    "I may opt for a sliding box design of some kind, just a huge bag bellows of some kind sounds better (lighter) but I do need at least front tilt. "

    Why not build a 'Frankenstein', attach a box to the rear of a Graphics View I. You get fine focus and all the front movements possible. Your film holders will give you all the specs for a GG insert and rear frame size. Cheap,fast and easy.


    Just a thought.

  8. #18

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    The lens you want for extreme macro photography with an 8x10 camera is a Wollensak 3 1/2" (90mm) F/4.5 Graphic Raptar.

    It's a little tiny process lens about the size of a quarter. It could probably be fit into a Copal 00 or 0 shutter.

    It has the flattest field and sharpest focus from side to side.

    With about 30" of bellows, I could photograph a large ant and fill the whole 8x10 frame with it.

    Best,

    Ryan McIntosh
    www.RyanMcIntosh.net

  9. #19
    jimgalli's Avatar
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    Why not save yourself a lot of trouble and expense and just buy an ancient 8X10 Folmer & Schwing camera that I have in the garage. It has 3 or 4 removeable bed extensions and max bellows is 42 inches. It's ugly as hell but the bellows are near new so it will soldier on indefinitely. It isn't worth much. $275 plus some shipping. Have you priced 14" pipe?? Contact me offline if you're interested. With 42" bellows you could get to 2:1 with a 240mm G-Claron.

    Get a copy of the latest issue of Emulsion Magazine where I have an article about macro with 8X10.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

    http://tonopahpictures.0catch.com

  10. #20
    Murray@uptowngallery's Avatar
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    150 mm lens at 1:1 is 300 mm bellows extension because 150 mm at 150 mm is infinity focus.

    I haven't figured out the math for 2X - whether it's double the 1:1 (600) or just 1 more f.l. longer (450 mm).

    All nominal numbers above...

    Use that equation that looks like a bunch of fractions something like 1/f = 1/s + 1/o

    Uses image and object distances,

    Circular tubing, while sturdy, is a lousy match for rectangular filmholders insofar as the diameter needs to be much larger than the sides of the filmholder.

    If black plastic plumbing pipe is available (ABS?), it is supposedly visible-light-opaque, unlike PVC pipe.

    I got a lead from an architect to look for roof drain pipe rather than conventional plumbing pipe - apparently the very large diameters exist there. But the big stuff is heavy and expensive...and good luck finding a short length.

    If you are doing table top macro and don't care about field lightness, you'd be surprised how well a simple wooden box construction works with regard to rigidity and cost.

    Fitting moveable standards, probably rectangular, onto a round tube, is beyond my imagination's capacity.
    Murray

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