A short text, with photos, analyzes a portrait lens constructed by Derogy-France, based on the famous drawing by Josef Petzval of 1840. It briefly discusses, from this manufacturer, how the Industrial Revolution impacted the optical industry in 19th the century.
Brief article discusses the design, characteristics and ancestry of Wollensak’s Wide Angle Velostigmat lens and shows an image made with it on an 18 x 24 cm negative.
Article addresses the technical and historical aspects of the first lens actually thought, calculated and developed for photography, in 1840 by Joseph Petzval.
Excellent book on evolution of concepts about light throughout history. All back and forth movements about its corpuscular or wave nature are approached within the cultural context of each moment and the philosophical theological preferences of each scientist. At the end it shows how much science really can not have as purpose an investigation into…
Published in 1866 this treatise is a great introduction to the optics of the first decades of photography. There is a theoretical part about light behavior and the basics about lenses, but there is also a lot of practical information organizing families and progresses made in photographic lenses manufacturing. It can be found online at…
Calculator for easy assessment of photographic formula’s cost. You enter quantities, dilution, packaging and price and get right away how much one liter of that working solution costs. Very convenient to compare different formulas, purchased ready to use or homemade, and decide what suits you best in financial terms.
Find a compact set of chemical reagents, 8 in total, that will allow you to develop film and print B&W photographies. With instructions about mixing, using and cost considerations. A nice starting point if you are interested in setting up a photography darkroom and make your own chemicals.
Homemade pinhole cameras using packaging left overs, woodwork, 3D printing and camera parts. Features also pictures taken with them.
Article presents project to build a black and white photo enlarger head, with timer, using LEDs and Arduino platform. The result is high power and excellent contrast control for black and white work.
Article analyzes a practical case in which the use of RAW file, thanks to its greater depth of color, allows the exploration of areas of a photograph that in format .jpg would be lost.
Article explains why and how color-depth concept is necessary to express the array of different colors a digital system can handle. It clarifies why it must be expressed in bits, what that means in terms of color differentiation, when true-color is reached and why sometimes more than true color becomes highly desirable.
Made in the nineteenth century this lens is a simple achromatic doublet and follows the same constructive principle of the lenses used by Daguerre in his first photographs.