Thomas Weber - Photography

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Technical aspects of the Negative:
The negative should be plastic coated photografic paper. This PE-paper offers a better flatness as a baryt paper. The paper should have a fixed gradation.

Concerning speed and gradation, such a paper negative differs by large compared with a modern analogue film negative. To measure these factors I used the Ansel Adams Zone System, developed in the 1940th, and this is teached at american universities up to the very day. I worked out 9 DIN / 6 ASA and N+3 gradation. This extremely low speed results in "normal" exposure times of to seconds, with a N+3 gradation. The gradation of a paper type 1 or soft developed in a soft working developer like Dektol will result in a gradation 0. A modern film of a normal gradation offers a range of 11 f-stops to produce a full gray tone scale from black to white. A negative paper can only cope with a maximum of 8 f-stops. Especially to shoot pictures under bright sunlight conditions is a difficult act. High precision work and the decision from an artistic point of view which parts of the object should be represented in the print and which have to fade out in black or white, is a neceassity. Furthermore, photographic paper with fixed gradation are sensitive only for blue light. Therefore the grey tone scale of the object will never ever be represented in a natural manner. And, such paper negatives loose speed by 2 to 3 f-stops in the last hour of the day.

Scanning the Negative:
Of course it is possible to scan the negative but to print that out like a positive with the help of software. Two things should be mentioned: flatbed scanners will not show the fibre structure of the paper and the haptic feeling of baryt paper can hardly be copied by computer printing.

Calotype versus Kallitype:
The process of the Calotype presented by Talbot 1839 should not be mixed up with the Kallitype patented in 1889. This Kallitype had been popular in Europe until the 1920th. In the last years there was a revival of this process by the integration of IT-technology. The basis is a small frame negative or file (digital photography) which will be printed out as a large format negative for contact printing. Well, the artistic expression of a Kallitype is not comparable with a modern Calotype strictly following the concept of 1839.

© Thomas Weber 2010 - 2021