Pinhole dreaming yet again.

[Stephanie Brim]

I posted a thread a while back about an interchangable pinhole pinhole camera, but decided that I'd rather have two relatively normal pinholes instead. So I've decided to do a little craft work and some completely insane things as well.

The first one is going to be your typical camera which will cannibalize a box brownie. This means I'll have a 6x9 pinhole camera with, most likely, an 80mm focal length. I am planning to take the front of the brownie completely off so that focal length could change a bit.

The second one is a bit of a project. My goal is a 6x14 wide angle panoramic camera. The biggest challenge in this, I think, is that I'm probably going to have to make a curve for the film to run because wide angle and pinhole are already a dicey thing in some cases. Considering the larger format, I'm thinking about a 50-55mm pinhole for this one. Not TOO wide, but wide enough to really get a lot in there.

Someone send me a Dremmel...I'm about to make SOMEONE proud.

 

[Jim Jones]

You might find many ideas and much information on F295. A great site with links to much more information is Dead Link Removed. The main advantage of cannibalizing a box Brownie to make a pinhole camera is for the greater depth of field. Except for that, and the satisfaction of a camera that is partly your creation, the unaltered Brownie is a better camera. Pinhole cameras have more advantages in wide angle coverage. They are the most practical way to image onto curved film.

You can use flat 6x14 film. Some pinhole photographers use pinhole lengths of 50mm or even less for this. There will be some fall-off in sharpness and more fall-off in illumination at the corners, though. Curving the film reduces these problems somewhat and makes images that are impossible in traditional photography. The film can be curved around the walls of a cylinder with the pinhole also in the wall. This is the traditional "Oatmeal can" camera. The film can be curved equidistant from the pinhole. This makes an image more like the traditional rotating Kodak Circuit camera. The film can be curved around the walls of a cylinder with the pinhole in the end, not the wall, of the cylinder. The F295 forum has had examples of each of these. Making a camera that allows you to use uncut roll film for several shots without reloading complicates the design.

 

[reellis67]

Here is a link to a panoramic pinhole that someone made, and somewhere I have photos of an interchangable pinhole lensboard I made for my 4x5 field camera. If I can find them I'll stick them up here.

Dead Link Removed

- Randy

 

[Stephanie Brim]

You might find many ideas and much information on F295. A great site with links to much more information is Dead Link Removed. The main advantage of cannibalizing a box Brownie to make a pinhole camera is for the greater depth of field. Except for that, and the satisfaction of a camera that is partly your creation, the unaltered Brownie is a better camera. Pinhole cameras have more advantages in wide angle coverage. They are the most practical way to image onto curved film.

You can use flat 6x14 film. Some pinhole photographers use pinhole lengths of 50mm or even less for this. There will be some fall-off in sharpness and more fall-off in illumination at the corners, though. Curving the film reduces these problems somewhat and makes images that are impossible in traditional photography. The film can be curved around the walls of a cylinder with the pinhole also in the wall. This is the traditional "Oatmeal can" camera. The film can be curved equidistant from the pinhole. This makes an image more like the traditional rotating Kodak Circuit camera. The film can be curved around the walls of a cylinder with the pinhole in the end, not the wall, of the cylinder. The F295 forum has had examples of each of these. Making a camera that allows you to use uncut roll film for several shots without reloading complicates the design.

I'm a complicated kind of girl.

The design is going to be the hardest part of making the pano camera. I figured I'd start by looking at people's designs for 6x12 and 6x18 models. I already know that I'm going to have to curve the film. I'm probably just going to buy a decently large amount of foamcore board and make several prototypes to do actual tests. I'll be trolling Evilbay for expired film quite a bit in the next few months. Once I finally get something that works, I'll make a final camera and then post the instructions on how I did it.

The hardest part about the design is going to be how I'm going to work the rollfilm. I have an idea in my mind of how it *could* work, but I wouldn't really be sure if it *would* work until I tried it. The entire project is incredibly ambitious and insane, but that's perfect for me.

 

[Stephanie Brim]

Here is a link to a panoramic pinhole that someone made, and somewhere I have photos of an interchangable pinhole lensboard I made for my 4x5 field camera. If I can find them I'll stick them up here.

Dead Link Removed

- Randy

That's pretty much my idea only slightly larger. Heh. I don't feel quite as insane anymore. Thanks.

 

[Greg_E]

You could use a curved back and line it with felt. That would keep the film pressed against the curved film guides. Not sure if it would cause static though.

 

[Greg_E]

Here's a pretty good look at another camera with a curved back, doesn't show everything you need to build one, but might help with the idea. Also notice that it isn't curved enough to prevent the light fall off at the edges. To do that do as suggested above, draw a circle with a radius the same as the focal length, that is the amount of curve that you need. http://www.f295.org/Pinholeforum/forum/Blah.pl?b-cc/m-1157947093/


Beware the thin plywood! It takes 2 heavy coats of black paint on each side to block the light using 1/16 inch thick aircraft plywood! Even laminating two pieces of wood together to get 1/8 inch thick isn't enough, you will still need to paint it heavily. Krylon ultra flat camoflage paint seems to get the nod, the rustoleum flat black is not really a flat paint. Not sure if you've seen both of these:
http://www.f295.org/Pinholeforum/forum/Blah.pl?b-cm/m-1156365080/
http://www.f295.org/Pinholeforum/forum/Blah.pl?b-cm/m-1150676255/

Also, in case you haven't used it yet, you should find Pinhole Designer to help with things like exposure times, and pinhole sizes. Pinhole size is something I need to play with again, now that I have a camera that is worth the effort. previous failure is at:
http://www.f295.org/DIYforum/cgi-bin/forum/Blah.pl?b-misEquip/m-1150231036/
and the resulting images:
http://www.f295.org/Pinholeforum/forum/Blah.pl?m-1155354692/

 

[Jim Jones]

You could use a curved back and line it with felt. That would keep the film pressed against the curved film guides. Not sure if it would cause static though.

Don't worry too much about keeping the film pressed against the curved film guides. Pinhole depth of focus will cover any problems. A channel that doesn't restrict the film might make film winding easier. Also, foam core has a fairly high coefficient of fridtion. Covering the film guides with tape or painting with something that doesn't disolve the foamcore should help this.

 

[Stephanie Brim]

Hehe...this is going to be fun.

I'm thinking of spending a couple hours in Hobby Lobby this week looking at materials. I'm thinking of using a light wood, but not plywood, due to the fact that it's going to be winter soon and I'd like my pinhole to survive the elements. Suggestions on that are appreciated and encouraged. Considering the amout of wood I'd need, price isn't really as much of a factor as I'd once thought...but I'd like to build the mammoth camera for under $100 if possible.

 

[Greg_E]

Don't use balsa sheets, the light goes right through the thinner stuff. You might just want to plan on painting the inside and outside with a couple of coats of paint. Or other people suggest using black felt to line the inside of the camera, which helps cut stray reflections, and should help block light coming through the wood. I haven't tried this yet, so to me it is still theory.

The 1/16 inch plywood is nice to work with since you can cut it with a utility knife, but keep the light transmission in mind. You might want to pick up some thick gapping filling Cyano-Acrylate glue to put it all together. Some files and sandpaper might come in handy too. Good old elmers glue would be good if you need to laminate two sheets of plywood together. Plywood thicker than 1/8 inch might help with the light leaks, but it is also much harder to cut (you'll need a saw). You'll want some gaffer tape (not duct tape) to hold things together while you decide if you cut them right. Duct tape leaves behind a sticky goo that will mess up the wood when you try to paint it.

I'll probably make more things with the 1/16 inch plywood (I have 1 and a half sheets of it left), it's just that now I know I have to paint it before testing!

 

[John Koehrer]

What about using part of a 2# coffee can for the back of the panorama camera? Painted black on the inside with a small lip top & bottom to hold the film in alignment?
Or just make the camera from the earlier mentioned can?

 

[Stephanie Brim]

I actually thought about using plywood and then lining it with thinner foam...that 1/16th inch foam that you can get almost anywhere in the kid's art section. That stuff is light tight last I knew and rather durable.

The coffee can idea is a good one and it gave me a really great idea...but I'd *definitely* need a Dremel for that one.

 

[Greg_E]

Cordless Dremmel can be nice.

If you do get some 1/16 inch plywood, check it with a flash light. And if no light goes through, let me know what and where to get for any future cameras that I make. I wonder if you can get 1/16 inch MDF? Guess I'll have to look.

 

[PhotoPete]

I have had good luck making pinhole cameras with the masonite (?) panels that Home Despot sells as "Handy Panels" It is similar to MDF, but much lighter and you can cut it with an exacto or utility knife. It comes in a few sizes and at least two thicknesses and takes a coat of matte black paint very nicely. I have never had any problems with light penetrating the material itself.

 

[Greg_E]

Ahh.. Thanks Pete! I'll have to have a look at that stuff. If it has the rough surface on one side like Masonite, that would be great for the inside of the camera. The texture plus flat black paint would really help kill reflections.

I'm already starting to think about building a 6x7 camera made on a Mamiya RB or RZ film back to add to my 645 and 35mm camera. Probably even try to keep the rotating feature of those backs.