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59

The first photographic images printed in newspapers were actually wood engravings meticulously hand-copied from a photograph printed in the normal way. By the 1890s, however, prints were made in essentially the same way they are today: through halftoning — printing different tones as patterns of small dots varied in size and spacing. By the 1929s, this ...


49

Stieglitz and his photo, "The Steerage" are hailed as great not because of its compositional excellence (at least one aspect of the composition is brilliant, and some of the lines in the frame can be seen as a kind of "proto-Cubism"¹) or the technical merits of the photo. "The Steerage" is most significant because it was one of the first times a photograph ...


35

It is related to a heated substance, albeit in a somewhat theoretical way. The substance is an ideal incandescent black body, which would radiate a given color within a given color space at a given temperature. The location within the color space vs. temperature is called the Planckian locus, and I don't claim to understand everything in that article, but ...


35

Before roll film there was sheet film. With sheet film a photographer could select particular films with particular emulsions individually for every shot they took. Applicable characteristics of a film's emulsion would include sensitivity/film speed, fineness of grain, color response/balancing, contrast, as well as the overall 'look' that different films ...


27

Wikipedia's introductory statement on color temperature relates them quite well: The color temperature of a light source is the temperature of an ideal black-body radiator that radiates light of comparable hue to that of the light source. Black body radiators are an idealized concept, that radiate an energy spectrum with a peak intensity at a frequency ...


24

Luna 3 did something as complicated as you thought: It took photos on a film, processed it in a kind of onboard minilab, and then scanned and radioed it back home in analog way not unlike an old fax. Funniest part was that Soviets didn't have the technology of radiation-hardened film, but Americans did. They used it against Soviets in high-altitude spy ...


22

Kodak started making "pocket" cameras in 1895, and each new design used a different film format — different sizes, aspect ratios, cartridge types, and orientations. By 1908, they decided to simplify the confusion with a numbering scheme, calling that first format "101" and continuing the numbering up from there. So, that's the scheme — the numbers correspond ...


21

You are correct that the term "macro" means large scale (e.g. macroeconomics), however its use in photography is relative to microphotography, that is imaging using microscopes. The tradition definition of a macro lens is one that can achieve a 1:1 magnification, which means the image projected onto the recording medium is life size. So for a common APS-C ...


21

My antique wooden Kodak™ day-light loader (ca. 1905) was made with a removable spool of thin (now quite brittle) perforated celluloid with raised rubber edges. The film was sandwiched between the layers of the roll. The celluloid strip was wide enough to accommodate all sizes from miniature to very wide 128 (2½" wide!). The roll of film was wound inside ...


19

Amongst the myriad online pages documenting the Viking series, here's one which states clearly The Viking Lander camera design was very different from vidicon framing or CCD array cameras. The lander camera was a facsimile camera with a single, stationary photosensor array (PSA), and azimuth and elevation scanning mechanisms. A lander image was ...


17

The colour temperature is related to the black-body radiation produced by hot objects. The black-body radiation curve, shown below, shows the approximate intensity* curves at each wavelength for the radiation emitted by bodies at 5000K, 4000K and 3000K. * It actually shows the spectral radiance curve, which is a kind of flux. But you can think of it as an ...


16

The original cameras didn't use film at all, so there was no noise from any film advance mechanism. Instead they used materials that were inserted in the back of what we now refer to as view cameras while being protected from exposure to light. Each image required changing out the entire back of the camera and replacing it with another glass plate that had ...


15

That particular ring, by itself, is the aperture stop. The normal operating mode of the Land Camera (150, at least) was a coordinated exposure system that coupled particular shutter speeds and apertures using the EV system. From the Land Camera 150 user manual, The shutter dial adjusts the camera to the right combination of shutter speed and lens ...


15

I'm guessing you're referring to the Lytro by Lytro, Inc. It's an example of a light-field or plenoptic camera.


15

The first mainstream applications for electronic image sensors (be it Image-Orthicons, Vidicons, Plumbicons, or CCDs, or CMOS active pixel sensors, be it analog-electronic or digital workflows) were in video, not in still images. Video followed form factors similar to movie film. In movie film, 35mm (equivalent to full frame still) or even 70mm were ...


15

What is the purpose ... for the existing convention? Math. It's because in many equations regarding simple optics, the ratio N = ƒ/D (where N is the ƒ-number, and D is the lens (or more often precisely, entrance pupil) diameter) pops up a lot, or the use of the ratio simplifies the expression or understanding of the expression. Example 1: The hyperfocal ...


14

According to this NASA PDF, Apollo 7 and 8 did not take hand-held cameras, instead using vehicle mounted Maurer or custom-built cameras. Apollo 9 had a Hasselblad Superwide, Apollo 10 had no hand held cameras, and Apollos 11 through 13 had custom built Hasselblad Lunar Data Cameras. Apollos 11 and 12 also had a 'Closeup Stereo ALSCC' camera. There is a ...


14

Just my notions, but some people did not take so many pictures. It might take weeks or months before they would expect to accumulate 36 exposures. Rolls of 24 were a little less expensive, and less to process, and served the immediate need better. About the same reason you might buy only a few tomatoes at the grocery store, instead of a bushel. Roll film ...


13

I was the one who prepared the camera for this mission, It was a Zeiss-Ikon Contarex Special; everybody could buy this model. Because the Astronaut was wearing a bulky helmet, he could not get his eyes close enough to the viewfinder so the prism viewfinder was taken off. The lens was a normal Tessar 2,8 50mm ste at f/11 and 15ft. The camera was brought to ...


13

While radiation above the atmosphere is indeed higher than on Earth, it is not so high as to ruin photographic film as quickly as your question would imply. The amounts you reference from NASA are exposures during a mission, not a short space walk. In a NASA study on photographic film sensitivity during the shuttle years, NASA basically found that radiation ...


12

I was apprenticed to a photoengraving company in 1946. We used the Colodion or Wet plate process to make halftone negatives and a glass cross line screen. Newspapers used a coarse screen with 55 to 75 lines per inch. Magazines used from 100 lpi to 150 lpi depending paper and press used by the printer. The glass plates were hand coated with iodised colodion ...


12

You might look at the Wikipedia Photography Technology timeline. A few key points from that reference: 1909 – Kodak produces 35 mm motion picture film on an acetate (less flammable) base 1913 - Kodak introduces panchromatic film (approximating the color sensitivity of the eye - older emulsions were not very sensitive to red light). 1925 - These innovations ...


10

A RAW file is a container format which includes metadata (proprietary and standard), possibly a JPEG-compressed preview, and a digitized record of the value of each sensor photosite, possibly with some low-level noise reduction applied and with dead pixels removed. This is common across the class of file formats we call RAW. Pure, "raw" sensor data alone ...


9

Six-20, also known as 620, is the film size that fits your camera. The film itself was the same as the more standard 120 film. The only difference is the size of the spool upon which it is wound. A 120 spool will not fit in most 620 cameras. Unfortunately, no one currently produces 620 film. If you have two 620 sized spools you can wind 120 film onto 620 ...


9

First, the real money for Kodak, Agfa, Fuji, Konica etc. was the amateur market. Kodak had built its business on the “Brownie”. This profit channel was the camera itself and its film. Camera sales fueled the sale of photographic paper and the chemicals of the process. Additionally their existed a worthwhile market for automated developing and printing ...


9

The crank is for rotating the prisms in front of the lens. Prismatic lenses place prisms in the optical path of the lens. These provide a unique special effect. If you look at the front of the lens in the photo you can see several small prisms have been placed in front of the lens. The hand crank rotates them in much the same way that one would rotate a ...


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