Film vs. plates and monochromatic/coherent light

This is a forum exploring Lippmann photography.

Film vs. plates and monochromatic/coherent light

Post by Ejs12006 » Thu Apr 30, 2009 6:44 am

Due to an unfortunate accident in which all of my pfg-03m plates were apparenntly exposed, I am now trying to use PFG-01 film (not plates) to make lippmann photos.

I am concerned about using film because I keep reading that it is very important to make sure the gelatin is not disturbed on a microscopic scale. If the flexible film is bending a lot while it is used, which seems unavoidable in my experience, I would think that there would be all kinds of wierd distortions within the gelatin that might disturb the laminae. William Aulschuler, a researcher at the california institue of arts, has apparently made lippmanns with film, but It is unclear whether he keeps the film flat by gluing it to a glass plate or something.

Also, I am trying to first make successful images with a monochromatic source, specifically, a sodium lamp. I understand that using a single-wavelength source increases the coherence length, which results in more layers within the emulsion. What I am wondering is if this also means that a reflecting surface, if used, need not be so close to the gelatin. Apparently, mercury or the gelatin-air interface is necessary as a reflector since the coherence lenght of white light is just 1.5 microns, and these situations are the only ways to get a reflective surface this close to the emulsion. If the coherence length of monochromatic light is substantially longer, would using a regular front surface mirror pressed up against the film work? This is something I am experimenting with literally as I type. I am also experimenting with using a laser as a lightsource, for the same reasons.

One more question: I read that omitting the fixing stage is recommended since fixing can shrink the emulsion and collapse the laminae. But if the film isn't fixed, won't it continue to be photo-sensitive, darkening when exposed to light? or would this only happen if the film is then re-emerged in developer?

Colin Kaminski

Film vs. plates and monochromatic/coherent light

Post by Colin Kaminski » Thu Apr 30, 2009 1:09 pm

Before you give up on your PFG-03 try this:
Jeff Blythe wrote:I have successfully killed bad fogging on Slavich plates (without also killing the photosensitivity) by soaking them for exactly 60 seconds in a solution of;

20g Ferric EDTA and 10 g KBr per litre. (This solution keeps for years.)
(Ferric EDTA is ethylenediaminetetraacetic acid ferric sodium salt)

What amazed me was that the photosensitivity of the plates did not drop noticeably afterwards without my needing to resensitise them in say 2% ascorbic acid (vitamin C) at pH ~6.
Some batches of PFG-03 seem to fog even in the dark.

Colin Kaminski

Film vs. plates and monochromatic/coherent light

Post by Colin Kaminski » Thu Apr 30, 2009 1:20 pm

Even if that does not work the gelatin on the plates can be striped of silver and reloaded with a diffusion method. Search for diffusion method.

Holography does not rely on a mirror for making the fringes. The fringes occupy a volume much larger than the plate.

In holography we often laminate film emulsion side out to a glass plate and use it as if it were a plate. I am pretty sure index matching a mirror onto film is not sufficiently close to form a Lippmann image. However I have not tried it.


Film vs. plates and monochromatic/coherent light

Post by LarryD » Thu Apr 30, 2009 1:37 pm

From the Wikipedia regarding sodium lamps: "These lamps produce a virtually monochromatic light averaging at a 589.3 nm wavelength (actually two dominant spectral lines very close together at 589.0 and 589.6 nm)."

While I have not made lippmans, I do know that PFG-01 has spectral sensitivity centrered at 632.8nm. You may hardly get anything (I have not tried, though.)Since you mention you may try a laser, If you have access to a red HeNe laser, Iwould try that first (on the PFG-01 film).

Ed Wesly

Film vs. plates and monochromatic/coherent light

Post by Ed Wesly » Thu Apr 30, 2009 4:05 pm

Regarding the fogging of PFG-03M, I got from no less than an authorities of Hans Bjelkhagen and Stas from Geola that the insanely tiny 10 nm grains are not fogged but oxidized by air since the surface area to volume ration gets nutty. You an get a factory freh box and they will develop black without ever seeing any light. "Erasing" them in the above formula works!

I have seen Lippmanns done by Nick Phillips using sodium vapor lamp illumination, done on Agfa film. He laminated the film to metallized mylar using an organic solvent which evaporated, leaving the reflector film in intimate contact with the photo-sensitive emulsion. There is a paper in an SPIE Proceedings regarding these images.

Using the monochromatic light source was a big help, especially with film, as there is a micron or so protective scuff coat layer on top of the light-sensitive coating, which might even space the light-sensitive coating further away from any fringe action. The narrow the bandwidth, the greater the coherence! Shoot your images with laser and sodium and see what you get!

And you are correct in predicting the final hologram or Lippmann will still be light-sensitive without the fixing, especially if there is silver halide of some sort or another in it, one of the dirty little secrets of holography. They will print out in time, especially if left in sunlight!


Film vs. plates and monochromatic/coherent light

Post by walschuler » Wed May 06, 2009 7:06 pm


I have used film in plateholders without mounting it on glass. This worked fine. Make sure the holder is flat black inside to avoid stray reflections, and the emulsion faces away from the camera lens.

I have tried Phillips' method, using unprotected aluminized mylar as a mirror mounted on the emulsion with various volatile organic liquids. This works. With a sodium lamp diffused as the subject, I got bright color shifted to the green from this (yellow) source, and an image which showed the bumps in the mirror film. (See my long post on the laywomen thread near this one.) In effect I got a hologram of the mirror film without a laser but of only about a fraction of a mm depth. Using such a lamp as illumination in a dark room I got (false) colored Lippmann images of real objects.

The sodium coherence length is about 3mm (see the laywomen thread). It should make the distance issue for mirror contact go away if the light is a line source like sodium. But for white light the coherence length is about 1 micron, so it remains an issue.

Water can be used as a mounting liquid, but then emulsion swelling is an issue. 100 years ago Herbert Ives made silver film-coated collodion, then floated that onto his Lippmann emulsion, silver side in contact. Collodion is more permeable than mylar, so drying was relatively quicker. He could easily peel the collodion off after exposure. That is said to have worked well, though I have seen no actual images that are demonstrably by that method. Note that collodion, the basis of the old Wet Plate process, is made using ether and other nasty stuff.

Try also making a spectrum. A cheap diffraction grating placed in front of the camera lens will give a nice continuous spectrum of an incandescent, a semi-continuous one for a flourescent (mercury vapor lines poke up through the phosphor continuum), and a line spectrum for a clear mercury vapor lamp. The yellow D lines of sodium are too close together in color to show up as separate lines in this simple arrangement, and sodium otherwise has a rather sparse set of colors, so it is of less interest for recording a spectrum.

Ed Wesly (above) mentioned holo film having a protective coating over the emulsion. I know that is the case for Fuji film, so I would not choose that for broadband Lippmann experiments, but that is not true as far as I can tell for Agfa, Slavich, Color Holographics, Gentet, or Ilford products. I have used Agfa 8E-75, Slavich PFG-01 and -03C.

Please write me if you like.


P.S. That defogging technique is a neat trick!