Thinking of a summer project - Some general questions about pin holes

hoffy · Dec 14, 2011

Howdy all,

I have been thinking about a summer project to use up some of the piles and piles of MDF I have sitting in myshed. Well, last night, I read through many of the posts through here and have decided that a pinhole might be a nice project and possibly a good intro into camera buildign (somethign I want to do, but maybe in the distant future).

So, with this in mind, I have questions!

Camera size - I have been thinking of doing an 8x10 - from what I can see, this shouldn't be any different to any other 'single shot' pinhole. Am I deluded? Or is 8x10 OK for a first build?
For a start, I would prefer to play with paper negatives. While I found a few hints in relation to using them (I.E., shoot on an overcast day, ect), I am a little unsure about a few specifics. Would I process a paper neg in the same way as a print? Will this be sufficient to get started? As I have exclusively printed on Ilford in the past, this will be where I will start, but is there a specific paper that people recommend?
I had a quick look at Mr Pinhole last night and his camera design page. From what I saw, if I made a camera with a Focal length of 170mm and a pinhole of 0.55mm, I should get an 8x10 done OK. Are these calcs correct?

I am sure I will have many more questions. At the moment, I am thinking of a design that is not reliant on Film holders, but having a removable back, that if I got clever with, could take a dark slide and then ultimately I could create multiple holders.

Any advice is more then welcome!

Cheers

jordanstarr · Dec 14, 2011

Great project...I'm thinking of 4x5 or 8x10 pinhole myself. I'm leaning more towards 4x5 as I don't have an 8x10 enlarger. However, 8x10 contact sheets would be nice to work with.

1. 8x10 isn't too big. It actually is probably easier in terms of handling the materials to build it than say a 35mm panoramic pinhole.
2. Yes, definately start with paper to see if your design is flawed and if you're getting the characteristics you want.
3. I would personally build one for holders. If you ever wanted to get into negatives, that's the only way to go. Getting them flat would be a pain and it would take you forever to bracket a particular scene. At least with holders you can shoot 4 photos in 10 minutes as opposed to 4 photos in a few hours. It will save you time in the end. Not sure if his calculations are perfect, but from what I've read, that seems pretty close. Others might have different experiences.

Good luck -keep us posted on how the project is going.

hoffy · Dec 14, 2011

OK, where is a good resource for film holders? They are not too common on the ground where I am..... Even if I could get the dimensions for a common holder, I could at least still build the camera around that, but also build the MDF back for now.

Also, I don't have a 8x10 enlarger either (I can only go to 6x7cm), so the intention was to contact print. That was another question. How fuzzy would an image get contact printing paper on paper?

polyglot · Dec 14, 2011

I reckon an 8x10 would possibly be easier to build, but holy cow 8x10 film is expensive. I would personally go for 4x5 with a slot to suit the normal 4x5 double-sided holders. The bonus there is that if you do it right, you could even put a rollfilm back on. Or maybe 5x7 since that's a common paper size and a reducing back for 4x5 won't look completely silly on it.

I would seriously consider making it a zoom, i.e. have a simple sliding-box arrangement (or bellows if you're extremely keen) so that you can change the position of the pinhole wrt film and therefore field of view. Of course the pinhole itself needs to be quickly replaceable to deal with size changes. And if you get that far, you've built a complete LF camera - replace the pinhole with a shuttered lens and there you go (GG for focusing optional).

Obviously you want a tripod thread in the bottom.

tomalophicon · Dec 14, 2011

For a holder you could use an 8x10 speed ezl if you were using paper negs. They are fairly common as far as I know.
Check out Blanco Negro Supplies' website. They have cheap 8x10 film at the moment.

Contact printing paper is fine. I wouldn't be worried about fuzziness using pinhole cameras

Pinholemaster · Dec 14, 2011

8x10 pinhole camera is my size of choice. Love the look and feel of the 8x10 negative over 4x5.

Have fun!!!

hoffy · Dec 14, 2011

polyglot said:
I reckon an 8x10 would possibly be easier to build, but holy cow 8x10 film is expensive. I would personally go for 4x5 with a slot to suit the normal 4x5 double-sided holders. The bonus there is that if you do it right, you could even put a rollfilm back on. Or maybe 5x7 since that's a common paper size and a reducing back for 4x5 won't look completely silly on it.

I would seriously consider making it a zoom, i.e. have a simple sliding-box arrangement (or bellows if you're extremely keen) so that you can change the position of the pinhole wrt film and therefore field of view. Of course the pinhole itself needs to be quickly replaceable to deal with size changes. And if you get that far, you've built a complete LF camera - replace the pinhole with a shuttered lens and there you go (GG for focusing optional).

Obviously you want a tripod thread in the bottom.

Hence why I wanted to start with paper!!!! I have to admit that I hadn't seriously thought about film usage, but was just trying to cover all bases, in case. When I started looking last night, I had thought about the Ilford direct positive paper, but I see there are supply problems with the RC variant, but that is something I could look at in the future.

As for the sliding box, yes, that was going through my head (at around 2am this morning....dammit. Have I ever said I over think things!), but I thought for a first off, I would keep it simple. Bellows is another project (for another time).

Tripod mount - yep, that was a given and shouldn't be hard to cater for.

Klainmeister · Dec 14, 2011

Make it with possible lens mount so wet plate isn't outta the question. Or is that just me?

hoffy · Dec 14, 2011

Klainmeister said:
Make it with possible lens mount so wet plate isn't outta the question. Or is that just me?

No, it's probably not just you. But as above....another project, another time.....

X. Phot. · Dec 14, 2011

8x10 is a good size. Contact prints from that size are respectable. Optimally if you could acquire the 8x10 film holder, you can design your camera around it. A simple lightproof box used as a single-shot camera could do this job also. My experiments show if a 2x yellow filter is used for contrast adjustment, normal RC VC paper, fl=14"-15" or so, pinhole ~ .65mm, on a bright sunny day you could expect exposures of 6-8 minutes or even longer. Having a camera that is solid, and that doesn't move around in a breeze is important.

ced · Dec 15, 2011

See the link below and maybe jon.oman still has the plans of his very nice 8x10 shown at the link.

(there was a url link here which no longer exists)

Rick A · Dec 15, 2011

I'd go 8x10 and find a couple of cheap film holders. You can use printing paper, direct positive paper, or X-ray film, which is relatively cheap.

bdial · Dec 15, 2011

You can make sharp prints from paper negatives. I suppose they may not be quite as sharp as a film negative, but it won't degrade a pinhole image significantly.
Note that when you make a print from a paper neg, you place the neg emulsion side to emulsion side with the print. The light is diffused some through the paper, but it isn't much different than what happens in a diffusion enlarger anyway.
Building it to take a standard holder is a good idea, but you could save that for a V2 since you have lots of material .

One small problem with using standard holders with paper is that a 8x10 sheet of film isn't quite 8x10 inches, so to use paper you'll need to trim it down slightly. The other problem with 8x10 holders is that they tend to be expensive, though you can get cheap ones that may need some repair and spend some sweat equity. Even with a cheap holder though, it will probably be the most expensive portion of your camera.

You can process your paper neg just like your prints in the same developer.

Ric Johnson · Dec 15, 2011

Paper negatives... 8x10 format... camera making... Make sure you go into f295.org to get all the details you will need. Joe VanCleave (member of f295) is the master.

X. Phot. · Dec 15, 2011

bdial said:
. . . One small problem with using standard holders with paper is that a 8x10 sheet of film isn't quite 8x10 inches, so to use paper you'll need to trim it down slightly. The other problem with 8x10 holders is that they tend to be expensive, though you can get cheap ones that may need some repair and spend some sweat equity. Even with a cheap holder though, it will probably be the most expensive portion of your camera. . . .

Oooooh . . . This could be a trouble spot. I can say from my 8x10 holders that half will accept paper, and others will not. On the holders that won't, the trough on each side rail is too narrow for normal double-weight paper. Film slides in just fine. You may want to ask the forum in advance if a particular make and model of holder will accept a certain thickness of paper. It could save you the heartache of ordering a holder that won't work with certain papers.

Jim Jones · Dec 15, 2011

Film and film holders are more readily available and less expensive than 5x7 or 8x10. The experience gained in building and using the smaller size may be valuable when designing a larger camera. Larger film (or paper) sizes do have a modest advantage in image quality.

This is because the image blur is proportional to the pinhole diameter. The ideal diameter (for maximum sharpness) increases in proportion to the square root of the focal length. Therefore, if the focal length is doubled, the blur is only 1.4x as large. For the same reason, wide angle pinhole cameras can have better central image sharpness than longer focal lengths. However, edge sharpness and illumination suffer in wide angle pinhole photography.

I prefer film over paper in the camera. It is easier to capture quality images on film. Paper has limited color response and demands more careful exposure. Exposure errors in film are easier to correct in printing. When printing, images on film can be interpreted in more ways than those on paper. The higher cost of film is small in comparison to the investment of time and energy in making and using pinhole cameras. With care, film can be processed in the same developer as paper. I often do this to increase contrast. It may also increase grain, which shouldn't be important in an image that has little detail and might never be enlarged.

For well over a hundred years there has been much (and sometimes heated) discussions on the optimum pinhole diameter. For maximum sharpness it is more critical than many claim. I prefer Pinhole Designer with a user constant of about 1.4 for optimum on-axis sharpness with film. With this criteria, the diameter for a 170mm focal length could be about .43mm mm for film and a little smaller for paper. The diameter might be increases a bit to sacrifice a little central sharpness for better corner sharpness with wide angle pinholes. Few lenses make an image as unsharp as a pinhole photograph. Sharpness is not the main goal in pinhole photography. More important is how pleasing or effective a slightly unsharp image can be.

keithwms · Dec 15, 2011

Well if you're going to get into the expense of 8x10 holders then you may as well buy and old 8x10 field camera, like a poco or korona or such.

I would suggest making some nice, low tech wooden boxes and just make a door to slip some film in and clip it into place. You don't need anything fancy like a holder for pinhole- the film can be quite curved and still give a nice result. In fact, a paint can with a hole in it might be just the thing. If you ant to get fancy you could come up with some sort of bellows or sliding mechanism to optimize the effective focal length.

For film size, let me suggest 5x8- you get two sheets per 8x10 and the print size is quite nice. You might try some ortho film, that should be fine and you can easily develop it by inspection, which is handy with pinhole.

It's pinhole- be inventive and quirky and you'll get something nice!

hoffy · Dec 15, 2011

Howdy and thanks for your responses thus far. I am going to stick with the 8x10 and a focal length of 170. From there, I will play with different diameter holes.

As for film holders, it nearly appears that where others live, they are a 5c a dozen! OK, maybe not quite, but around here they are not necessarily gathering dust in every second garage. If there are more cameras in the future, Im sure I could come up with one to suit a 4x5 holder (which makes more economical sense if I want to use film). Also, this is kind of an exercise in playing with power tools as much as taking photos (Geez, Im starting to feel like Tim Allen all of a sudden.must go and find a raw steak smoothie). I must, though, resist the urge to go and buy new materials! I checked last night and found that the majority of MDF I have is 12mm, so its going to be a chunky unit! (My other hobby for a while was slot cars. I built a slot car track out of MDF, hence why I still have a bit laying around)

So, tonight when I get home from work, Ill draw up some plans and see about making a start on the weekend.

I do have many more questions in relation to using paper negs, but I am sure that these can wait (dont want to put the horse before the cart!)

Cheers

LumbisK · Dec 15, 2011

I built a pinhole with 4x5 film holders and it works great. I have a 4x5 enlarger so that's what I went with. A resource I used was on YouTube and it was a 10 part series on building a 4x5 pinhole camera. Just type that in and it should show up. Of course everyone modifies the instructions to fit their own needs and intuitions and I made a few myself. Anyways, this will give you an idea on a design for a holder style pinhole and you can just size up the basic concept to fit an 8x10 holder. A lot of the stuff he goes through is just basic woodworking so you can fast forward through some of the parts. Have fun.

Tom Miller · Dec 15, 2011

8x10 is good. I do a lot of work with 11x14 paper negatives, but in a tin can, not in film holders. 4x5 photo paper has to be cut down slightly to fit into a 4x5 film holder. I don't know if the same thing applies to 8x10 or not; but it may be a consideration.

For paper negatives... I've tried a lot of papers and have settled on two. Oriental Seagull mat surface RC Grade 2 and Foma Variant 312. The Seagull is twice as fast, has incredible detail but is a little flat for some people's taste. Foma Variant has a lot of detail and is more contrasty. Still, the Foma picks up a pretty good tonal range. I've tried Ilford MG RC and found it way too contrast with blown-out shadows and highlights. Most other papers lack a good tonal range as well. I haven't tried Arista RC Grade 2, but a lot of people use it with good results. See what works best for you.
Pre-flashing the photo paper will reduce contrast and may make Ilford workable.

Also, paper negative do work better on overcast days; but I've had excellent results in pure bright sunlight when the brilliant sunshine covers the entire scene to be photographed. It is when the scene has sunlit highlights as well as shadows when paper negative don't work so well.

yeknom02 · Dec 16, 2011

No way, I am doing nearly this exact same project...!

I decided on an 8 inch (203mm) focal length, and just made a wooden box to fit some Lisco 8x10 holders that I picked up for cheap on eBay. Of course, film holders aren't 8" by 10", so I just traced an outline on wood and cut it to actual size. I ordered my pinhole from Lenox Laser in MD. The camera is nearly done, but I want to add some elastic to add some pressure to the back of the camera and hold the film holder in place. I may add a shutter, though the darkslide will probably make a good shutter as well, given that I'm going to start with paper negatives.

I have not worked with paper negatives before, but I have heard that a yellow filter or a 00 filter will help control contrast, and pre-flashing might also help.

SMBooth · Dec 17, 2011

Making a 4x5 or 8x10 is not much of a project, is a 30min job.. For a project you need to build a 40mm 6x6 roll film pinhole. But if 8x10 is the choice then a 140mm- 200mm range is nice, try sourcing Xray film,l you could get it from here (http://dlc.com.au/en/x-ray-equipment/x-ray-film.html) but check the Christmas thing.
Don't forget to download Pinhole Designer off web (http://www.pinhole.cz/en/pinholedesigner/), and go to f295.org.

Thinking of a summer project - Some general questions about pin holes

X. Phot.

X. Phot.

Privacy & Transparency

Privacy & Transparency