page_title: Paper texture effects in calotype photography
section_title: Paper vs. negatives on glass
hierarchical_section_title: Paper texture effects in calotype photography / Paper vs. negatives on glass
caption_attribution_description: English: Repeat image of boulders from a silver bromide/gelatin on glass negative. The benefit of eliminating paper texture is evident.
context_page_description: Paper texture effects in calotype photography limit the ability of this early process to record low contrast details and textures. A calotype is a photographic negative produced on uncoated paper. An important feature is that a relatively short exposure in a camera produces a latent image that is subsequently made visible by development. Then positive images for viewing are obtained by contact printing. This technique was in use principally from 1840 into the 1850s, when it was displaced by photography on glass. Skilled photographers were able to achieve dramatic results with the calotype process, and the reason for its eclipse may not be evident from viewing reproductions of early work.
context_section_description: To understand why the calotype process could sometimes produce attractive results but was found to be generally unsatisfactory, it would be useful to compare pictures of the same subject taken with first paper and then with glass (or clear plastic film) as the negative substrate. An easier way to gain insight into the destructive effect of low contrast spurious texture is to view a relatively large format (not 35 mm) photographic negative in contact with a piece of tracing paper by transmitted light. Positives can be made with a digital camera and digital image processing so that the two cases, with and without the tracing paper, can be compared side by side. Viewed from a distance, the image made through the tracing paper may seem satisfactory. But from closer up, the paper texture will appear more intrusive and begin to camouflage low contrast scene details. This comparison will also demonstrate that paper texture is relatively coarse and, unlike pixelation in a typical digital image, does not quickly become inconspicuous as the distance from which it is viewed increases. Here it is significant to note that the scale of mottling in paper correlates to the average fiber length, which is on the order of millimeters, rather than to the much smaller fiber width.
caption: A contact print from a silver bromide/gelatin on glass negative. The same camera and the same contact printing process (cyanotype, reproduced here in gray scale) were used to make both images.
exif: {}