Zone plates

[Rolleiflexible]

I'm building an 8x10 pinhole camera from a dilapidated Kodak Metalview camera. I've come across some intriguing images online made with "zone plates." They seem to work well with hign-contrast subjects and bright specular highlights. A quick search of APUG, however, uncovers no discussions about them.

Anybody here using zone plates for pinhole work? I've located posts on other sites via Google, but I was wondering whether anyone on APUG has first-hand experience using them.

Sanders McNew
prenatal pinholer

 

[Jim Chinn]

Stricly speaking a zone plate is not a pinhole, but both zone plates and pinholes fit under the umbrella of lensless photography.

F295 is a site that has a forum and galleries dedicated to lensless photography and adapted cameras and optics:

http://www.f295.org/

If you can get over to a Borders bookstore, there is a book called Adventures with Pinhole and Homemade Cameras. the Borders here has it on the shelf from time to time and it has a nice section on zone plates, slit plates and pinholes.

This is a link to a page at Zero Camera listing Zone plates, adaptors for copal shutters and other pinhole accessories.

http://www.zeroimage.com/web2003/EntryPage/entryFrameset.htm

 

[juan]

I've tried one - put it on a lensboard for an old Speed Graphic so I can use the focal plane shutter. I got a zone plate of 120mm - close enough to the Speed's original 127mm for me to use the focusing scale and not have to try to see the ground glass at f/80.

I've made only a few images with it and don't quite know what to do with it. I'm sure something will come to me. The images are not very sharp, so the choice of lighting and subject matter is important.
juan

 

[erikg]

They have a real glowy kind of effect, like a true soft focus lens, so backlight really helps. Here is another resource for info and places to get stuff: http://www.pinholeresource.com/

 

[Rolleiflexible]

I've tried one - put it on a lensboard for an old Speed Graphic so I can use the focal plane shutter. I got a zone plate of 120mm - close enough to the Speed's original 127mm for me to use the focusing scale and not have to try to see the ground glass at f/80.

I've made only a few images with it and don't quite know what to do with it. I'm sure something will come to me. The images are not very sharp, so the choice of lighting and subject matter is important.
juan

Juan, is f/80 about where these things have to be exposed?

Sanders

 

[smieglitz]

Stricly speaking a zone plate is not a pinhole, but both zone plates and pinholes fit under the umbrella of lensless photography.

However, a pinhole is technically a zone plate with the number of zones reduced to 1.

The effective aperture for any zone plate is f/90 when matched to the proper focal length.

A few images I shot long ago using 2475 Recording Film follow. The first two are blue-toned silverprints, the third hand-colored, and then an unmanipulated zone plate print image:

Using high-speed recording film enabled me to hand-hold a 35mm using f/90 in bright daylight. Plus, I always liked the extended red sensitivity and graininess of that film. Nudes on 2475 printed on Ektalure G were very tactile and my favorite combination. Sigh...

Zone plates always worked best for me in high contrast lighting situations and once in awhile specular highlights added to the effect.

Joe

 

[AgX]

There is a lens-less optic related to the zone-plate called sieve:

http://ca.geocities.com/penate@rogers.com/sieve/photonsieve.html

 

[Rolleiflexible]

Joe, your second image captures what I thought the zone plate would produce with figure work, properly lit against a dark background. Interesting. Sanders

 

[juan]

Juan, is f/80 about where these things have to be exposed?

Sanders

I bought my Zone Plate from Pinhole Resource and they say f/80 is the proper stop. I usually compute exposure at f/90, as that is easier to figure. I use BTZS and the Palm program, and exposures work out as well for the Zone Plate as they do for a lens.

The images are different - I plan to do more experimenting to learn how to best use the features.
juan

 

[Ross Chambers]

Zone plate pic

This is what I found when shooting a subject with hardish, contrasty edges. It seems typical of zone plate results.

Regards - Ross

 

[tpersin]

Chris Ellinger, in my opinion, is a master of the Zone plate. His work may be seen here:

http://www.f295.org/gallery/main.php?g2_itemId=316

 

[AgX]

Are there photos around made in parallel by using a pin-hole and a zone plate?

 

[Jim Chinn]

A zone plate is a series of concentric circles with a single center apeture. The center serves basically as a pinhole IIRC.