Modern Lippmann Photography Hans I Bjelkhagen Hansholo Consulting

Modern Lippmann Photography Hans I. Bjelkhagen Hansholo Consulting Ltd www. hansholo. com Lippmann January 2004

Interferential Imaging • Images which are recorded in such a way that the information is stored as an interference structure in a suitable recording material • A very high resolution recording material is needed • The colour is recorded as a b/w interference pattern in the depth of the emulsion. The colour of the image is not caused by dyes or pigments in the emulsion, it is caused by light reflected off the recorded interference structure • Lippmann Photography is unique since it records the entire spectrum of an object or scene. It is a direct recording method of colour in the camera. Lippmann January 2004

Recording Principle Lippmann January 2004

Modern Lippmann Photography • New recording materials, silver halide emulsions and photopolymer materials • No mercury, the emulsion-air interface is use to reflect light back into the emulsion • When using air as the reflector, no limitation to the size of plates to be recorded • A foil of sputtered silver can be laminated to the photopolymer recording film, which acts as the reflecting mirror • Applying new chemical processing techniques when using silver halide emulsions, to obtain images as good as photographs recorded with mercury Lippmann January 2004

Light reflected at the interface between the emulsion and mercury or air a: Light reflected at an optically thicker medium (Mercury) b: Light reflected at an optically thinner medium (Air) Lippmann January 2004

Camera for Modern Lippmann Photography Lippmann January 2004

Auto Graflex 4” by 5” Camera equipped with a Kodak Aero Ektar f: 2. 5, 178 mm lens Lippmann January 2004

Dark slides for 4” by 5” plate camera Lippmann January 2004

Negative (Reflection) Lippmann January 2004 Positive (Transmission) Colour Image (Reflection)

Recording materials • Panchromatic isochromatic materials required • Possible materials: – Silver halide emulsions – Photopolymer materials Lippmann January 2004

Commercial holographic silver halide emulsion suitable for Lippmann Photography Slavich PFG-03 c: Emulsion thickness Grain size Resolution Blue sensitivity Green sensitivity Red sensitivity Colour sensitivity peaked at Lippmann January 2004 7 μm 12 - 20 nm ~ 10000 lp/mm ~ 1. 0 - 1. 5 m. J/cm 2 ~ 1. 2 - 1. 6 m. J/cm 2 ~ 0. 8 - 1. 2 m. J/cm 2 633 nm, and 530 nm

Viewing Lippmann photographs: A 10 -degree glass wedge is cemented on to the plate Lippmann January 2004

Examples of recorded plates by Bjelkhagen The following 4” by 5” Lippmann photographs were recorded with the Auto Graflex camera equipped with the Kodak Aero Ektar f: 2. 5, 178 mm lens Recorded in Slavich PFG-03 c emulsion Recorded with air reflection only The finished plates have a 10 o glass wedge attached to the emulsion side Lippmann January 2004

Lippmann photograph on silver-halide emulsion Elephant This plate of the elephant was recorded on the 12 th of May 1999 at 2 pm in Leicester, UK. The exposure time was 3 min 15 s at F: 5. 6 and recorded in a Slavich emulsion. The golden metallic reflections are very realistic looking in the Lippmann photograph. Lippmann January 2004

Lippmann photograph on silver-halide emulsion Chicago Skyline with Sears Tower This plate was recorded on the 5 th of July 1997 at 3 pm from the top of Rush Hospital Parking Deck. The exposure time was 1 min 15 s at F: 4 and recorded in a Slavich emulsion. Lippmann January 2004

Lippmann photograph on silver-halide emulsion Bjelkhagen Self Portrait The portrait was recorded at Lake Forest College, Illinois, USA, on the 2 nd of July 1997 at 2 pm in direct sunlight. A diffusing screen was held above the subject's face to reduce the amount of glare off the face. The exposure time was 2 min at F: 4 and recorded in a Slavich emulsion. Human skin is very accurately rendered in a Lippmann photograph. Lippmann January 2004

Publications on Lippmann photography by Bjelkhagen 1. H. I. Bjelkhagen: Lippmann photographs recorded in Du. Pont color photopolymer material, in Practical Holography XI and Holographic Materials III. Proc. SPIE 3011, 358 -366 (1997) 2. H. I. Bjelkhagen, T. H. Jeong and R. J. Ro: Old and modern Lippmann photography, in Sixth Int'l Symposium on Display Holography. Proc. SPIE 3358, 72 -83 (1998) 3. H. I. Bjelkhagen: New optical security device based on one-hundred-year-old photographic technique. Optical Engineering 38, 55 -61 (1999) 4. H. I. Bjelkhagen: A new OVD based on interferential photography recorded in holographic materials, in Holographic Materials V. Proc. SPIE 3638, 87 -95 (1999) 5. H. I. Bjelkhagen: Lippmann photography: reviving an early colour process. History of Photography 23, (No. 3), 274 -280, Autumn 1999. 6. H. I. Bjelkhagen: The Lippmann OVD for enhanced document security, in Optical Security and Counterfeit Deterrence Techniques III. Proc. SPIE 3973, 276 -283 (2000) 7. H. I. Bjelkhagen and S. De Souza: Computer simulation of the Lippmann photographic process and recording experiments using holographic materials, in Practical Holography XV and Holographic Materials VII. Proc. SPIE 4296, 300 -311 (2001) 8. H. I. Bjelkhagen: Lippmann photography: its history and recent development. The Photo. Historian, Journal of the Historical Group of the Royal Photographic Society, APIS 2002 Special double edition, PH. 141 -142, pp. 11 -19 (2003) 9. H. I. Bjelkhagen: Lippmann Photography: A highly innovative OVD based on existing photographic techniques. Keesing's Journal of Documents 1, Issue 2 (2003) Lippmann January 2004

Contact Details Dr Hans I. Bjelkhagen Email: hansholo@aol. com www. hansholo. com Lippmann January 2004