Sticky

Here is my tip, as promised
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Here is what I consider to be the most important tip if you want to really take awesome pinhole photos.

Your pinhole camera has an F-stop

A hole of y diameter that is z away from a surface will allow x amount of light through. It don't matter if there is \$4000 worth of Leitz glass around this hole, or if it is open air. F/stop is an F/stop. I seen a lot of people put out ugly pinhole work during college, and I'm pretty sure all of them didn't realize this, so instead of using any knowledge of exposure that they may have had, they pretty much shot from the hip and had to deal with print muddy, underexposed images. All it takes is a little applied math to make it work.

1st Measure your pinhole. This can easily be done if you have access to a film scanner, or a high resolution flat bed scanner. Scan the pinhole at the highest optical DPI your scanner can muster, and use photoshop's measure tool to figure out how big it is. This should get you within 0.001 inches of the diameter, which is plenty.

Now just take distance that you will be mounting the pinhole from the film plane, and divide it over the pinhole size. So, if your hole is 0.018”, and is mounted 4 inches from the film plane, you have;

4/.018 = f/222

Armed with this number, there is no reason to throw away what you know about making exposure when using pinhole.

What does f/222 mean for this example? Look at a typical f-stop progression

2.8 – 5.6 – 8 – 11 – 16 – 22

Numbers just keep getting bigger, though in most usage, it stops around 22. Lets keep running with it.

11 – 16 – 22 – 32 – 45 – 64 – 90 – 128 – 180 - 256

We've just put our pinhole camera's f-stop in relation to the typical scale. Roughly about 2/3rd a stop past f/180.

Meter your scene as normal. I happen to have light meters that can dial in pretty much any f/stop if I know the proper compensation, so a good chuck of math in the field is removed for me. If you don't have a nice fancy external meter, you can meter though your normal camera, or use an estimation off of sunny-16.

Lets say you bring your DSLR, and meter the scene at f/11 & 1/200th. Based on the list above, you need to add 8 2/3rd stop to this exposure. So start doubling.

1/200 -> 1/100 -> 1/60 -> 1/30 -> 1/15 -> 1/8 -> ¼ -> ½ -> 1 -> 1.66 Seconds. Not too bad. Keep a reciprocity table with you for the film you are using, and calculate that on top of this if the end exposure falls into the range that requires it.

You'll now have a nice a nice perfectly exposed pinhole image, that will scan/print in exactly the same way as every other negative you'll make that is properly exposed.

The semester that I did this in college, I was churning out prints from my pinholes that had tonal ranges no worse then anyone else's lens-based photos. The professor even asked me how I was getting such amazing results with pinhole. In all of her years she hadn't seen any one else be able to print their pinholes with such a full tonal range. I told her I was simply exposing the exact same way I expose everything else.

I'll try to get some of my best work from that semester up later tonight.
Note: I'm slim on time tonight, so I didn't include quite as much detail as I'd have liked. So ask questions if you have them.
great, where is my math background when I need it?!?!?!
Well, you seem to know what you are talking about. Its going to take a bit for all that to sink in...
;)

Tip #2: Bring a calculator.
Tip #2-alternate: Visit mrpinhole.com and use his calculators to print off a handy exposure chart.
LOL, yeah a calculator would help!
Ill check mrpinhole out later tonight.
And just to prove that I'm not just making this stuff up, I uplaoded some of my images from early 2003 when I started doing this. Set is Here.

And to be even more in your face:

Kip,

How do you (personally) measure distance to the film plane? I think that that would be a touchy thing if you wanted to get the focus bang on.

I've seen so many awful pinhole photos, and these are fantastically sharp. I'm really interested.

Jason
I personally stick a tape meaure through the opening until it hits the film plane. ;) I do leave some element of roughness in my pinhole work.

For the one's I just posted, I was using a rapax shutter with the lens elments removed, and made plugs with my pinholes attached that were pushed snug up against the aperture blades. So measuring to the blades was obviously precise enough.
There is a mark on your camera (usually) that indicates where the film plane lands -- it is a line with a circle through it on the top of your camera. The line is parallel to the film plane and you can measure to the pinhole from there.

By the way, those of you doing this with digital cameras (and I have done it, look here, you don't need any math skills if you "chimp" -- take a look and if it is too dark, add time, too light, take away time!

By the way, focusing is not the issue because the small aperture has virtually all things in focus anyway with the HUGE depth of field.
"By the way, focusing is not the issue because the small aperture has virtually all things in focus anyway with the HUGE depth of field."

Ah, makes sense.

Curious -- why have I seen so many blurry, OOF looking pinhole shots? Camera shake?

Jason
MOD
diffraction is an issue though, especially if its not well made...this is why your optimum sharpness with most lenses is about f11-16 not wide or stopped all the way down, but the actual aperture for optimum sharpness depends on the lens...
anyways, those images are very sharp! why is the light falloff so great? usually it gradually vignettes and its not in a perfect circle like that...those resemble a circular fisheye more than a pinhole.
not bashing or anything but why is this?
To have an actual shutter, and to minimze any camera shake, I mounted my pinhole near teh aperture blades of a large format shutter without a lens. The sharp vignette actually due to the threads where the front element would normally screw in being within the field of view.

Here is an unprocessed image from before I pushed the tones of the threads area down into a black abyss. Should make more sense now.

Curious -- why have I seen so many blurry, OOF looking pinhole shots?

From mrpinhole.com - Pinhole diameter determines image sharpness and the intensity of light falling on the film. Diameters smaller than the optimal diameter may cause unacceptable levels of flare in the picture. Larger diameters allow for shorter exposure times and make pictures fuzzier

Every focal length has it optimal diameter, and pinhole shape plays a part in it as well. Most people just stab a hole which usually isn't the optimal size, or anywhere near being perfectly round. When I made my hole for that project, I sat at my desk for a few hours punching & scanning holes until I finally got one the optimal diameter that and wasn't oblong. I still have a scan on of the holes holes that I made hiding on my server. Dated 09-Jul-2002. Dang. Doesn't feel that long ago.

For fun, this is my first pinhole try.

This was shot on a defunct Kodak Tourist folder, with quick and dirty measurements and assembly. Yes, I did make my "lensboard" out of corrugated cardboard. Yes, I did make my pinhole with an actual pushpin. My scanner told me that it was roughly f/113. I think I calculated reciprocity wrong; I underexposed this by about 4 stops.

If you can't tell (I'm surprised if you can!) it is a guitar case leaning up in the corner.

Jason
Now THAT'S a photo to submit to the deleteme group!

Jason
What I've learned about pinholes so far:

It's really hard to poke a hole smaller than .025 inches or so in just about any material.

I've made my pinhole camera and loaded it. I'll waste some time running around at work and make some exposures.

Jason