Lippman serendipity

[Tom B.]

Just found a couple of gems while searching for practical info on Lippmann photography:

Holography, Art and Design - Selected papers from the 2002 London Conference http://www.holography.co.uk/Conference/confindex.htm

One of the papers, "Super-realistic-looking images based on colour holography and Lippmann photography" by Hans Bjelkhagen has some good practical info on color holography and on the Lippmann process. It seems that the nasty toxic mercury reflecting layer is not really needed and the gelatin-air interface can be made to work fine. Hey Colin, you've got some PFG-03C, why not give it a try? I've only browsed a couple of the more artsy papers so far and was impressed by Jo Fairfax's energy and creativity.

The Kubota Holography Lab http://homepage2.nifty.com/kubotaholo/indexe.htm

A previously unknown site. No Lippmann color, but some very nice images of color holograms. Refreshingly different subjects - Japanese kitsch objects instead of Western kitsch Also some utterly amazing movies of reflection and refraction of light wavefronts made using a holographic technique with a picosecond pulsed laser. You can actually see light in flight!

[Tom B.]

Papers from the 1998 conference:

http://www.holography.co.uk/information/downloads1.htm

Some of the titles looked familiar, but the contents were new to me. I think some of the links were not working last time I checked here. They work now.

[Colin Kaminski]

Thanks for the link, it took me a couple of days to digest it.

[Colin Kaminski]

Ok Tom, you planted the seed. What would be the simplest method for generating a lippman photograph? I noticed they used color film but is it really necessary? Isn't the color made from the layers of silver in the emulsion?

[Tom B.]

The way Lippmann color works is that incoming colored light from a focused image passes through the emulsion, then immediately bounces back into the emusion from a mercury layer, or just an air-emulsion interface as Bjelkhagen describes, forming interference fringes of very limited depth (less than a few micrometers) due to the incoherent source. When developed and properly lit, the fringes produce a interference filter, like a reflection hologram, which, when lit properly, reconstructs the original colors of the image with irridescent colors like a butterfly wing or oil on water.

The neat thing about this processs is that it is black-and-white, with no color filters. But to get good color, the recording film must be panchromatic - responsive to many wavelengths, like for example PFG-03C.

[Colin Kaminski]

I guess that makes sense. If I wanted to see a green or blue object I would need pan-chromatic film even though the color would not be made like a photograph. Now that I think of it it is the same for a true color hologram.

Any ideas on a simple camera? I am not willing to deal with mercury so I guess I would use an air gap.

I think I can make a black box to hold the film but a lens for imaging is another story. If I were to use a piece of film 2x2 I could not use a 35mm lens. I would think I only need a simple lens but it must be large diameter.

Any idea what kind of exposure times would be required? Can I get away with a manual shutter? Or will I need a timer.

Tom, are you going to try any lippman photography?

[Jean Dufrasne]

Colin,

Maybe you can build a simple pinhole camera ?
I don't know if that works ! It is just an idea.

Jean

[Colin Kaminski]

The problem I forsee is the amount of light required for a pinhole camera is very large as the apature is very small. It would make a shutter very easy. I wonder how one goes about figuring out exposure time?

[Tom B.]

For just fooling around, a magnifying glass taped to a hole in the side of a small cardboard box would do. You could maybe focus by moving the "camera" toward or away from the (still) subject, using white paper as a focusing screen. I think a pinhole would let through far too little light for reasonable exposure times on relatively insensitive holographic emulsions. Other than preventing the camera from shaking and blurring the image, I don't think there are should be any extreme stability requirements as in holography.

I think you have a optical power meter - you could stick that in the image plane and use the reading to estimate exposure time to get maximum density on the highlights. I don't know, though, what the optimum is for Lippmann color. You might want to increase or reduce the aperture to produce an exposure time long enough to allow use of a simple cardboard shutter.

I recently tried a series of experiments with a similar setup using red-sensitive film, thinking it might at least record reddish subjects. I was able to make black-and-white images, but I was able to see no color at all. I then realized that I didn't really know what chemistry Bjelkhagen was using, the exposure requirements, whether the film needed to be bleached or not, or how best to view the results. Currently the project is on the back burner until I have more information or think of something different to try.

[Colin Kaminski]

I think bleaching would be required as it is a phase image, i think?

Also I have seen information at Photographers Formulary on Lippman photography. I didn't know what Lippman photography was at the time so I didn't really pay attention.