Wednesday, March 21, 2018


One day Sarah and I were breaking down shipping boxes to be recycled. I opened one in which Sarah had received a very nice scarf. It was rather thin for corrugated cardboard and the inside was completely lined with gold foil.   My first thought was: "You could make a pinhole camera out of that."

I asked Sarah, if I were to make her a new camera for Worldwide Pinhole Photography Day, what characteristics would she like it to have. I've made two cameras for her for Pinhole Day before.  One was wide horizontally but kind of narrow vertically, and other was rather wide angle.  She replied: "I'd like one that sees normally like I do."

It so happens that I've never made a 120 Populist in the normal range.  I've always had a funny reaction to that word normal, and I never really did a lot of photography with a normal lens or pinhole. It does sound dreary. Normal. I shouldn't knock it. Cartier-Bresson, Kertész, Frank and a lot of others did most of their work with normal lenses.

So it's 80mm long on a 6x6cm frame with 120 film.

For winders, we looked through the collection of Scotch, cordial and olive oil corks and Sarah chose this pair from bottles of Port.

The viewfinders are map tacks that I dipped in Gold Testors Paint.  It was a little weird re-encountering a product that I had used to paint model cars when I was 10 years old in the exact same little bottle with the same labeling it had almost 60 years ago.

The corrugated cardboard turned out to be not bad to work with.  It was a little thicker than cereal boxes so I had to modify the back a bit on the fly while I built it, but it fits together pretty well.

I drilled a .32mm pinhole.   As usual, smaller than the calculated optimum, but remember that's a measure of diffraction, not sharpness. That makes it f250.

I've learned my lesson not to give someone a camera that hasn't been tested.  I thought since the camera looked like gold, I would pair it with something that featured silver, it's neighbor one row up on the periodic table - black & white 100. Kind of a slow combination, but there were only a few hazy clouds and there's a big star fairly nearby that really lights up the landscape.

You know, the River Withywindle is named for the willows that grow on it's banks.

It's not Middle Earth, but I ventured forth on a journey around Oshkosh.

Looking over the ice on Miller's Bay.

Where Andy went to Kindergarten.

First Grade, down at the other end of the building.

Over to the University.  The shadow of a stair rail rippling down the steps of Halsey Science Center.

Just to the right, Buckstaff Planetarium.  Doesn't that name sound a little Hobbitish?

Down the mall to the modernist Polk Library in whose subterranean halls I labored for three decades.

A solar panel giving another spin on sensitivity to light.  This is starting to look more like science fiction.

Down the river to the somewhat brutalist former shopping mall which now houses several large businesses.

Just across the alleyway, along the river, the ramp to the hotel parking structure.

Further down toward the lake, the railroad bridge.

And from there, back again, up north past our first home in Oshkosh in the Dale School.

Looks like the camera is as good as gold, although it does still seem a little like magic.

Sunday, March 18, 2018

Building the Pinhole Lab Camera extension and some new materials.

I don't think I have to go into the construction of the Pinhole Distance Reducer. The Pinhole Distance Extension however, although made much like the camera, needs a few special methods.

Links:  Original Lab Camera Description    Construction    Feeding and Use    Link to Templates    Excusado    Reducer and Extension

The first step is of course to glue the template to card stock and cut out the parts. All the parts should be cut a little long.  Every camera is going to have a slightly different dimension, and we want to avoid gaps that could create light leaks. We'll cut them to exact length when they're wrapped around the box. Fold and glue the flaps to mimic the double layered sides of the camera back.

To keep the camera front rigid while you wrap parts around it, you'll have to remove the Pinhole Mount and as we did with the camera, place it in the camera backwards to prevent the sides from squeezing together while you wrap things around it. If you had made a couple of those Reducers, those would also serve well for this purpose.

You'll notice the use of clothes pins for clamps. In the past I've always used binder clips to clamp parts.  Binder clips work really well, but they have two problems.  They're only about 10mm deep so you could only really clamp the edges of a part, and they're almost a little too strong and can leave visible marks. Clothes pins are probably more readily available and per unit, probably much cheaper.  They're not as strongly sprung but that can be made up for by using several of them.  They usually come in packages of 50, so you'll probably have plenty. The gentler pressure also doesn't leave marks and they have a longer throat so you can clamp up to 25mm or so deep.

To start, wrap the Back Extension around the camera front and slide it into the light trap.  Mark where it overlaps and cut it for an exact fit. Since it's not glued to anything yet, you have to hold it together with a piece of tape until it's glued to other parts. It's also a good time to roughen the part where the light trap cover will be glued.

With the Back Extension inserted into the light trap of the camera front, place the Light Trap Extension inside the Back Extension. It should sit right on the Camera front. Mark it where it overlaps and trim it to fit. Try not to have both of the joints in the same place.  Put the two joints on opposite sides of the camera. Again, tape the ends together to hold it temporarily and then glue it in place and clamp it.  Here's a place where the longer reach of the clothes pins really comes in handy.

At about this point, I ran out of Aleens Tacky Glue and started using Elmer's X-treme School Glue, which I think is a little more widely available than Aleens (I got it at Walgreens).  I'm pretty happy with it, especially the dispenser cap that twists open and closed with one hand so I don't have to keep track of a cap, I think it dries a little faster than Aleens (15 minutes), and from using it on a couple other projects, it really does form a strong bond.

Place the Camera back over the Light Trap Extension.  It should slide up right against the Back Extension. Wrap the Light Trap Cover around and mark and trim to fit as before. Draw reference lines so you can make sure everything remains in place when you remove it from the camera front so you don't glue them together.  Roughen the area where the glue will go.  Mark the side of the Extension with the pinholes so you can place it back into the custom fit light trap.  The glued part is now a little far from the edges for clamps to reach, but you can use that infinitely adaptable clamp, the human hand, to hold it in place for a few minutes and read the New York Times or something until it sets.

Most of this will have double layers, but there's still the possibility that light might sneak through some of the joints, so it's probably a good idea to paint the interior.  I've always done that with a fast drying flat black enamel like Krylon, but that requires a pretty well-ventilated environment, has a tendency to get where you don't want it, and it's too cold to use it outside in winter in Wisconsin.

I bought an 8 ounce sample of Behr Ultra Flat Black interior latex wall paint on the internet from Home Depot.  I'm not sure you can get it that way in the store. I think Sherman-Williams also makes something similar.  It's kind of weird stuff.  It comes out of the can like tar and you have to thin it with just a few drops of water. If you get it too thin, it's not opaque.  It is almost completely odorless, cleans up with soap and water and dries to the touch in about an hour.  I used two coats anyway.

I noticed while taking pictures it had the tendency to bow in on the single-layer long side and block part of the image, so an extra layer of card stock on the interior of that side to stiffen it up might be a worthwhile addition.

If you're a regular viewer of our program, you know the next step. Go out with it and take pictures.

Monday, March 5, 2018

Pinhole Lab Camera Accessories: Pinhole Distance Reducer and Extension

How far the image-forming objective is from the film plane is one of the fundamental descriptors of a camera system.  Along with film size and aperture, it determines most of the visual and technical attributes of the image.

With lenses this is known as focal length. Determining it with lenses is complicated.  With my Canon FD 20mm f2.8 lens, the nearest piece of glass is 50mm from the film plane.  It takes a whole article in Wikipedia to explain it.  With pinhole, you can just measure with a ruler, or in my current case, cut the right size piece of cardboard.

One of the prime characteristics of the Pinhole Lab Camera is having two separate pinhole distances to experiment with -  2.5 and 4 inches.  That's a bit of a limited selection, and stays pretty well in the moderately wide angle segment of the range.

Two fairly simple accessories can expand the options available, and of course, impact the image.

A Pinhole Distance Reducer can be easily made by cutting 4 x 4 inch squares of another widely available material, corrugated cardboard, and gluing them together.  With the box I used, it took five layers to make a half inch.

Placing that against the back of the camera front (of course stuck on with a loop of tape), you can then place the paper at a 2 inch distance from the pinhole giving a 64 x 90 degree angle of view at f102 (with our .5mm pinholes), a 35mm equivalent of 18mm.

Adding a second reducer brings you to 1.5 inches, 76 x 106 degrees at f76, a 35mm equivalent of 14mm.

Making an extension to move the film away from the pinhole requires a part made from glueing a template to cardboard and folding and glueing as with the camera.  It's basically a two inch band the size of the camera back which fits into the camera front. It is then stepped down to the size of the front, with a light trap around the joint which the back then fits into.  It's sort of as if you cut off the front of a camera. The template is on-line, and I will be doing a separate step-by-step post on building it, including notes on a few new materials.

One of these extensions makes the camera 6 inches long,  23 x 36 degrees at f305, which brings us all the way out to the range often referred to as - drum roll - normal! A 35mm equivalent of 55mm.  Also we've finally gotten to where those .5mm pinholes are optimal according to Lord Rayleigh.

Finally a second extension (make two at once and save on glue-drying time!) will bring you out to moderate telephoto portrait range, 18 x 28 degrees at f406, a 35mm equivalent of 70mm. That f ratio is getting to be a whopper, with a sunny day exposure of two minutes with paper.  If we're just considering the width of the image, this is the same as the Moderately Telephoto Pinhole Camera in a Plain Brown Wrapper.

Here's a table describing the entire range.

Depicted graphically.

And where the photons hit the film plane.

At one and a half inches

Two inches

Two and a half inches

Four inches

At six inches

and at eight inches.

Here's one of those documentation shots that shows the relationship of things from the side.

Here's another sequence of the full range in a more confined setting.  The camera is up against the headrest on the rear passenger-side seat of a Mustang.

One and half inches

Two inches

Two and a half.

Four inches

Six inches

And all the way out at eight.

If Mazda wasn't already using it, maybe the motto of the Pinhole Lab Camera should be "Zoom, Zoom"

Saturday, February 24, 2018

Thin Lizzy

I've been saving this Guiness six-pack carton for some time.  I intended to make a 35mm camera to take on our trip to Europe, but something else got in the way, and I ended up taking another camera to carry in my pocket.

Although most of my cameras are somewhat wide-angle, I've shied away from the extreme end, mostly because I dislike vignetting, but that's kind of a limiting attitude, so this seemed like an opportunity to use the Guiness packaging.  A six pack doesn't really have enough cardboard to make much of a long camera, so it was a natural to go shorter. Supper Club Shorty brought me down to 35mm, so I did this one at 30mm - a 90 degree angle of view on a 6x6cm format.  I have made one camera this short before, but it had other issues.

The design is the same on both sides, but on the rear shutter, I lost the little round piece I cut out of the harp, so I thought the most appropriate substitution was the Art from Arthur Guiness's signature.

The winders are my standard 3/8 inch dowels whittled to fit in the slot of a 120 reel.  Because I like the look and the extra torque for winding I glued them into some cut-off cork stoppers.  The problem with this scheme is that the winders are only held in because they fit tightly into the slot.  The problem arises because different film manufacturers have different size slots.  If the winder fits tightly into the narrowest, it will fall right out of the widest.  The answer is that most pinholey of solutions, more tape. I place several layers of tape over the tab until it fits very snuggly into the slot and stays reliably put.

Otherwise it's a standard 120 Populist.

The optimal pinhole size for this distance to the film is .231mm.  After drilling several holes closer to .3, I quit when I got this one at .20 that looked pretty good.  That makes it f150.

I loaded it with Lomography 400 to try it out. I was surprised the vignetting didn't bother me that much.

The wide angle lets me get the entire fern stand in the dining room window without moving the dining room table.

One issue with extreme wide-angle is that if the camera isn't perfectly square with the subject it's particularly noticeable.

I did a little better this time.

One of my pet peeves with extreme wide angle cameras is that people don't get close enough to fill the frame.  You really have to get right in there with things.

Some times you get too close.  When I pulled open the shutter, it hit the subject and pushed it back a bit..  After a few seconds, I decided to stick the knife into the now empty foreground.

Buddha's corner following the post-Yule transition.

Sitting in my usual work space writing out a shopping list with a freshly baked loaf of bread and five pinhole cameras.