VC Magazine/Pinhole Photography - Role of Soft Images?

[Michael Heald]

Hello! I read the article about Pinhole Photography with interest. I made an 8x10 camera f375 with a focal length of 12 inches. I want to use it to make images that are not supposed to be sharp, that would complement alternative processes. I have cyanotype in mind.

My problem is that with the 12 inch focal length, the images look more like careless pictures that I let go soft, rather than images where the softness reinforces the image. With the wide angle images I've seen, the lightfall off (and sometimes circular borders, if that is what the photographer wants) emphasize the "alternative" nature of the pinhole images.

The few images that I've taken that I've liked have used motion as the theme of the image. As a result, I'm a stumped. Many of the images I had in mind when I built this camera I don't think will work because the camera doesn't emphasize the "alternative" nature of pinhole images enough at this focal length, particularly of landscapes

Whether by pinhole or lens, I'm curious what types of images folks have tried to take that purposely included image softness as part of the technique in order to emphasize the theme of the image. Best regards.

Mike

[Jack Flesher]

I'm no expert in soft focus techniques, but here's what I've learned from playing around with a soft-focus lens on my 4x5. And my opinion only, others will most certain vary:

I think the best soft-focus images are those with strong compositions of simple subject matter. I think those two traits help the viewer get beyond the fact the image is soft.

[Jim Galli]

Before you throw in the towel, try enlarging your pin hole. Larger the ph the softer the image. But of course there is a reason people are paying big $$ for Verito's and the like.

[alec4444]

Does anyone know of a place that can do the calculation for the optimal size pinhole for various focal lengths and then manufacture it? I've been toying with the pinhole concept too on a LF view camera. Was wondering if there is a person I can turn to and say, "I'm shooting 11x14 and I want a pinhole optimized for 6" of bellows draw, 12", and 18"....

--A

[steve simmons]

There is an e-mail address/web site address at the end of the article. Contact the author.

steve simmons

[Capocheny]

Google "Pinhole" and it'll give you plenty of sites to go to for information and products for sale as well.

Cheers

[Paul Hamann]

Alec,

There are a lot of pinhole calculators on the web. Here is one of them.

http://pinhole.stanford.edu/webphcalc.htm

Paul

[tpersin]

Hi Mike-
I'm glad to hear you enjoyed the pinhole article, and happier still that you've decided to give it a try! I have a couple of suggestions/ideas/references for you:

1. Mr. Pinhole is a great calculator for all your needs, everything from optimal pinhole size to image circle, focal length, etc. It can be found here: http://www.mrpinhole.com/calcpinh.php There's also a simple calculator on the f295 home page, soon to be expanded: www.f295.org

2. Check out f295.org. The pinhole/lensless discussion forum there will provide you access to a host of information and lots of other photographers who would be happy to lend a hand. http://www.f295.org/Pinholeforum/forum/Blah.pl

3. You might try decreasing the focal length of your camera. The light fall-off you refer to is a result of the image circle not fully covering the film. The camera you built has roughtly a 53degree angle of view, which while official "wide angle" you might want to try something around 4" to get the fall off you desire. At a 4" focal length your image circle would be 7.6" with an angle of view of 116degrees. you'd definitely see vignetting with that camera.

4. If softness is what you're after, you might try following Jims advice and enlarging your pinhole. The larger the hole the softer the image (but not infinitely inversely true!) The other thing you might try -if it's softness you seek- is Zone Plate. Chris Ellinger in MI uses crown graphic and zone plate aperture to achieve some wonderful images, you can see his work here: http://www.f295.org/gallery/main.php?g2_itemId=316

in regards to alecs question, i dont know of a site that both calculates and manufactures pinholes. Pinholes can be bought from Eric Renner at Pinhole Resource. A number of people also use apertures for electron microscopes, though I'm a strong advocate of self-manufacture ;)

Hope this helps.

Tom Persinger
www.f295.org

[Jack Flesher]

Here's a pretty nifty free download that does all the calcs for you: http://www.pinhole.cz/en/pinholedesigner/

[Jim Jones]

Mike -- Illumination fall-off in the corners of images from properly constructed pinholes should be no greater than for most lenses of comparable focal length. A pinhole image becomes softer when the pinhole is either larger or smaller than the size for optimum sharpness. The image from a larger pinhole looks rather like a poorly focused lens image. A smaller pinhole may give a more pleasant softness. Pinhole Designer in Jack's link is good. The optimum constant used in this calculator has been hotly debated. The often used Lord Rayleigh constant of 1.9 is popular, but gives a pinhole too large for optimum on-axis sharpness. Your 12" f/275 pinhole conforms to the Lord Rayleigh constant. It may be a good compromise between fairly good on-axis sharpness and improved sharpness well away from the image center. I prefer a user constant of 1.5, based on considerable testing. This gives better on-axis sharpness, but less sharpness towards the image corners. This characteristic can be creatively used.

If you play with PinholeDesigner, you'll discover that the shorter the focal length, the sharper the image. Like Tom says, this will cause decreased illuminatuion in the corner of the images. When the image covers a 90 degree angle, this fall-off will be two f-stops (or more, with a poorly fabricated pinhole).

Pinhole photography can be simple, or very complex. Lord Rayleigh's often cited paper on the subject http://idea.uwosh.edu/nick/rayleigh.pdf is an example of the latter. Matt Young's paper on the subject http://www.mines.edu/~mmyoung/PHCamera.pdf is much better. Jan Grepstad's site http://home.online.no/~gjon/pinhole.htm has information both excellent and trivial, and enough links to other sites to keep one busy for a very long time. The standard reference book on the subject is Eric Renner's Pinhole Photography: Rediscovering a Historic Technique, http://www.pinholeresource.com/agora/agora.cgi?cart_id=&xm=on&product=Books.

[Jack Flesher]

FWIW, you can change the constant in pinhole designer -- it just defaults at Rayleigh, but also has "first Fresnel" (2.0) and user set, so you can easily set Jim's favorite of 1.5.

Cheers,

[Michael Heald]

Hello! I first designed the camera based on some of the resources mentioned. I thought a "normal" focal length would be interesting in 8x10, that is, 12 inches.
The first few I tried I was excited about the quality of the images that th epinhole created. The next set I was disappointed because of teh sharpness issue. The images were too sharp compatred to many pinhole images I'd seen, but blurry for lens images. They looked like I'd tried to take an image with a lens and used poor technique.
What I found was something I should have considered all along - the pinhole is a tool that produces a particular kind of image. Those characteristics must be taken into account in order to aeffectively use the pinhole technique.
For me, with the longish focal length, the first type of images that worked for me included some sort fo motion - long waving grass, gentle waves, etc. To me, the softness reinforces the idea of movement in these images.
I've thought the portaiture might be another realm that pinhole owuld work well in.


I'm curious what types of images people think that softness work with - either pinhole or induced softness with a lens. Best regards.

Mike

[tpersin]

Mike -- Illumination fall-off in the corners of images from properly constructed pinholes should be no greater than for most lenses of comparable focal length.

i might argue (for the sake of argument) that this is a subjective statement and that a "properly constructed camera" is one that achieves the intent of the photographer/artist. I might also add that a perfectly legitimate intent is to produce a camera with extreme fall-off (ie: with a short focal length/extreme wide-angle) to produce a vignetted circular image. That said, Jim is correct in stating that a "normal" pinhole camera should have very little fall-off in the corners of the image -probably like the one you built Mike...

[JoeV]

Most of my pinhole cameras are square format, with focal lengths "normal" to "longish", meaning that my 8"x8" format camera has a focal length of around 11", operating at f/459.

I personally tend to favor square format in many of these pinhole applications, because, for me, I can use the square framing for lots of semi-abstractions within a landscape (i.e. closeups of details and patterns). I just like the look of square images.

Regarding Mike's question of 'too sharp' pinhole images, I've noticed over at f295 that there are many fine images being made with pinhole that are just fine images regardless of the type of camera or lens. And many of these are landscape or industrial/urban documentary type images where you would not normally choose pinhole just for a particular 'look'. I don't think a person should choose a pinhole camera as a means for generating a 'gimmick' look; rather, they are real tools that can produce very nice images. I think the motivation to use pinhole should be more philosophical, in keeping with one's personal vision.

For my personal working methods, I use paper negatives. 4'x4" or 4"x5" I will either contact print or enlarge onto 8"x10" fiber paper (yes, you can enlarge paper negatives); this tends to soften them a bit more, but they can still be surprisingly sharp. Larger formats I will contact print. A contact print of a well-exposed 8"x10" negative, from an optimized pinhole, can look just as good as an 8"x10" enlargement from 35mm.

I think the main thing to keep in mind is that pinhole cameras are real cameras, not just kid's toys, and therefore they can be used to make very nice images, under the control of a skilled photographer. Mike, if there's a certain genre that seems to work well with your pinhole camera, you should keep exploring that area.

As for the idea of going softer, with a bigger sized aperture. I experimented with what I call a "pencil hole camera", which is a 1/4" diameter hole, for a projection ratio of around f/35 on a 7" deep box camera. I used it to take images from TV screens onto paper negatives. With an aperture this large, even paper negative exposures of the light from TV screens is not unbearably long. This, of course, is an extreme example, but it illustrates that point that softness can be an asset, depending on what you're after.

Another point is that if you're interested in shooting extreme closeup shots of, for instance, dioramas and other miniature scenes, it helps to have a pinhole slightly smaller than optimal, because at close ranges the softening effect from direct geometric effects overwhelms any potential loss of sharpness caused by diffraction. Most formulae for optimal pinhole size are optimized to assume the subject is at infinity. So if you find your camera is too sharp for long-distance shots, try shooting close-in stilllifes or dioramas.