8"x10" Nested Box Camera

[Joe VanCleave]

http://farm5.static.flickr.com/4051/4423318639_0275fa4425_o.jpg

This new camera is nearing completion, enough so I was able to achieve "first light" this afternoon.

It's a nested box camera, employing a single-element meniscus lens (diameter ~4") that was salvaged from a photo-lithographic stepper (used in the semiconductor industry to print integrated circuit patterns onto silicon wafers). When finished, the front portion will be fixed to the bottom plate, with the rear sliding in and out for focusing. It employs standard Riteway-style 8"x10" sheet film holders.

http://farm5.static.flickr.com/4060/4423318675_54ee72c590_o.jpg

The camera is constructed from black foamcore, the front half is laminated on the outside with a thin, wooden adhesive laminate used for countertops. The rear of the sliding portion, made from scrap wood, employs a set of aluminum "L" channel to clamp the film holder, via thumbscrews, permitting an uninterrupted view of the rear, where I will insert a removable ground glass viewscreen, same thickness as the film holder.

http://farm5.static.flickr.com/4034/4424083854_1bf80aae5c_o.jpg

There is a removable aperture stop, behind the shutter; I only made two so far, the one used today is 3mm, giving a focal ratio of F/90, a hyperfocal setup needing little in the way of critical focusing. The other aperture stop is ~3" diameter, giving a focal ratio around F/4 wide open. I plan on making a set of various sizes.

The shutter is a simple guillotine shutter made from masonite, covered on the reverse side with adhesive craft felt, as is most of the inside surfaces of the box that aren't black foamcore, to absorb light reflections.

The camera will have two operating modes: 1) Hyperfocal mode, F/90, no critical focus needed; 2) Wide aperture, narrow DOF, taking advantage of the single meniscus lens's abberations to produce soft-focus images, for instance for portraits.

Since there is no mechanical shutter, I have to keep the shutter speeds >1 second, so the hand-operated shutter can be used accurately.

Today's first images were made using preflashed grade 2 paper negatives.

~Joe

http://farm5.static.flickr.com/4040/4423778886_e0be317221_o.jpg

[jtzordon]

Very nice first run!

[Allen Friday]

Beautiful camera. Well done.

[asp.artist]

Very nice!

[Joe VanCleave]

Several images from today's shooting with the near-finished camera. I'm still working on finishing the removable viewscreen. So for this afternoon's landscape images, captured along the foothills of the Sandia Mountains, I used a smaller removable viewscreen that I had made for a 4"x5" camera. The lens was stopped down to 3mm, about F/90, exposure ~3 seconds onto preflashed grade 2 paper negatives.

http://farm5.static.flickr.com/4064/4451974477_e5e330e81a_o.jpg

http://farm5.static.flickr.com/4034/4451974323_78ff6f5dea_o.jpg

Later in the evening, after processing the above images, I setup a still life composition in my shop, this time with the lens opened up to F/23 (accounting for bellows extension, nominally F/16 at infinity), 1 minute exposure, lit by a single low-wattage work lamp.

http://farm3.static.flickr.com/2756/4453328516_177eb1ccb4_o.jpg

~Joe

[Andrew K]

you've inspired me to make one - great work

[Joe VanCleave]

Last night I made some contact prints of negatives exposed yesterday. I came to the conclusion that the big meniscus lens just isn't as sharp as I'd like; in fact, comparing these contact prints with ones from a cardboard 8x10 pinhole camera (with optimized pinhole), the meniscus lens images are softer.

So I considered other alternative lenses I have at my disposal. One obvious candidate is my 150mm binocular objective, which I've used repeatedly in my Speed Graphic. It has incredible off-axis softness and blurr, depending on aperture, but knew it would be too short for infinity focus in the big 8x10 box camera. Still, for close-ups where bellows extension is the norm, I figured I'd give it a go.

I fashioned a bracket from scrap wood and foamcore that mounts the binocular lens in place of the meniscus. Surprisingly, it covers the 8"x10" format. So I concocted this still-life on my workbench, the main subject being my WWII-era Anniversary Speed Graphic. Preflashed grade 2 paper negative, 7mm aperture (f/38 effectively), 50 second exposure. You can see the reflections of my work light in the lens.

I'm pleased! :)

~Joe

http://farm5.static.flickr.com/4031/4460476775_59e15342b3_o.jpg

[Ektagraphic]

That is really awesome and inspiring!

[Mark Fisher]

The formica is a wonderful touch! It is really wonderful.

[premo]

I/m very impressed with the quality of the meniscus lens---especially the still life of the bananas. Is there a place to find these lenses for sale? I would like one to use on my R.O.C 8X10 with about an 18" focus.

[Jerevan]

Premo, you can get the same effect as shown above with a simple close-up lens. There's a formula for deciding the actual focal length (which I don't remember right now) but try a +2 close-up lens for a start and see where it gets you.

[Joe VanCleave]

I/m very impressed with the quality of the meniscus lens---especially the still life of the bananas. Is there a place to find these lenses for sale? I would like one to use on my R.O.C 8X10 with about an 18" focus.

I sure any single-element meniscus will give similar results; you can find these at optical places like Edmund Scientific and such.

This particular lens was salvaged from a Body 9 Nikon Stepper, used in the semiconductor industry to print circuit patterns on silicon wafers.

I've also since acquired a Fujinon Xerox 240mm lens assembly; it projects a pretty good image wide-open, but can't be stopped down using my usual method of waterhouse-type aperture stops on the front or rear of the assembly without severely vignetting the corners of the image. The ideal location for these aperture stops would be inside the lens assembly itself, between the lens elements. So for now, this new lens is used under dim indoor light for still-lifes and portraits.

Here's a view looking inside the camera, with the Fujinon Xerox lens installed:
http://farm5.static.flickr.com/4124/4965254407_4030760397_z.jpg

Here's a still life from the new Fujinon Xerox lens:
http://farm5.static.flickr.com/4150/4988214212_43ca0d3548_b.jpg

Here's a shot of the viewscreen (digital camera upside down) focused on my workbench:
http://farm5.static.flickr.com/4145/4965854400_38070bc254_z.jpg

Here's the new removable mechanical shutter that fits onto the front of the box camera. Still a work in progress. Rube Goldberg is rolling over in his grave...!!:
http://farm5.static.flickr.com/4138/4927790132_85453f61bd_z.jpg

~Joe

[Barry S]

That shutter is amazing, Joe. How about a video of it in action?

[2F/2F]

I/m very impressed with the quality of the meniscus lens---especially the still life of the bananas. Is there a place to find these lenses for sale? I would like one to use on my R.O.C 8X10 with about an 18" focus.

Keep in mind that you are seeing a digitized reduction of the negs.

[jford]

I love the still lifes. And that shutter could do some real damage. Where do you insert the victim's thumbs when seeking to extract information?

[Joe VanCleave]

Here's a full accounting of the shutter, over on F295 (http://www.f295.org/Pinholeforum/forum/Blah.pl?m-1282773633/). I don't yet have any video of it in action, but rest assured, one should take caution when it fires lest any unnecessary digits get lopped off in the process!

One more image taken with the Fujinon Xerox lens wide open indoors:
http://farm5.static.flickr.com/4103/4987441869_7b2896bce7_z.jpg

[Jim Chinn]

I made something similar a few years back to see if I wanted to get into 11x14. It closed into a box that when opened the front and back covers became the bed for the extension, about 34". It used homemade film holders and the ground glass was removed when inserting the film holder which was secured with a couple of sliding tabs. Since focusing was a bit "sticky" I eventually put axles with HO gauge train wheels on the two boxes and grooved the bed to hold HO gauge rails and built in a couple of screw locks. After I decided I wanted to pursue the format I built a camera out of aluminum with bellows, full movements etc that was a rail design but could be broken down for transport in the field.

[Mark Fisher]

For pretty much any size meniscus lens you want, look at Anchor Optics (cheap, commercial grade) or Edmund Optics (expensive, very complete selection). Surplus Shed is another great, cheap source. BTW, plano-convex and double convex lenses make equally great single element lenses. They get more fun used with a larger aperture, though (:

[jon.oman]

At Surplus Shed, they have a lens finder. The dropdown lists both negative and positive meniscus lenses. Which one should you buy for a single lens camera? I don't have a clue, but I have always wanted to try one out.

Jon

[Joe VanCleave]

You want a plano-convex, bi-convex or convex-concave lens, either of which is a positive type of lens. A negative lens is like a bi-concave lens, one that won't focus a projected image.

Then you want to select your focal length. This is mainly a personal preference based on expected angle of view with your desired film format. Figure a focal length that's near the diagonal of the film format is a "normal" angle of view. There may also be physical limitations of your camera setup, especially (like in my case) one's that are handmade and are limited by minimum or maximum focal length.

The diameter of the lens has to do with your maximum aperture (focal length divided by lens diameter). Keep in mind that with single-element meniscus lenses, wide open apertures have only a very narrow sweet spot, in the middle of the image, that is sharply focused. So therefore expect anything under, say, F8, to be pretty soft with totally out of focus edges. Therefore you can save some money on these lenses by opting for a smaller diameter lens; the extra diameter doesn't buy you much more usably sharp image area, since the lens has to be stopped down anyway.

~Joe