Misplaced Pages

#152847

26-425: Jarvik is a surname. Notable people with the surname include: Erik Jarvik (1907–1998), Swedish paleozoologist Robert Jarvik (b. 1946), American scientist and inventor A series of artificial hearts Lissy Jarvik (1924–2021), American psychiatrist Murray Jarvik (1923–2008), American researcher and scientist and late husband of Lissy Co inventor of

52-631: A lightbox and a loupe , which allowed rapid side by side comparison of similar images. A slide copier is a simple optical device that can be fastened to the lens mount of a camera to enable slide duplicates to be made. Whilst these devices were formerly used to make duplicates on to slide film , they are often now used in conjunction with digital cameras to digitize images from film-based transparencies. This method usually gives better resolution than using attachments for digital A4 flat-bed scanners . The devices are typically about 30 cm long, and screw into an intermediate ' t-mount ' attached to

78-416: A transparent base. Instead of negatives and prints , reversal film is processed to produce transparencies or diapositives (abbreviated as "diafilm" or "dia" in some languages like German , Romanian or Hungarian ). Reversal film is produced in various sizes, from 35 mm to roll film to 8×10 inch sheet film . A slide is a specially mounted individual transparency intended for projection onto

104-605: A controversial proposal regarding the origin of the tetrapods. He proposed, on the basis of detailed analyses of the snout and nasal capsule structures as well as the intermandibular, neuroepiphysial, and occipital regions, that Tetrapoda was biphyletic. In his view, the anatomical details of the Caudata (salamanders) bound them to the primitive " porolepiform " fishes, while all other tetrapods (“eutetrapods”) – apodans possibly excepted – were descended from primitive osteolepiforms. Thus, in his view Amphibia had arisen twice. On

130-432: A number of classical problems in comparative anatomy, including the origin of the vertebrates the origin of the pectoral and pelvic girdles and paired fins, and the homologies of the frontal and parietal bones in fishes and tetrapods Some of Jarvik's views did not accord with general opinion in vertebrate paleontology. However, his anatomical studies of Eusthenopteron foordi laid the foundations for modern studies of

156-518: A screen using a slide projector . This allows the photograph to be viewed by a large audience at once. The most common form is the 35 mm slide, with the image framed in a 2×2 inch cardboard or plastic mount. Some specialized labs produce photographic slides from digital camera images in formats such as JPEG, from computer-generated presentation graphics, and from a wide variety of physical source material such as fingerprints, microscopic sections, paper documents, astronomical images, etc. Reversal film

182-523: Is different from Wikidata All set index articles Erik Jarvik Jarvik was born at a farm in Utby Parish near Mariestad in northern Västergötland . He studied botany , zoology , geology , and paleontology at Uppsala University , where he took his licentiate 's degree in 1937. In 1942, he completed his PhD with the dissertation On the structure of the snout of Crossopterygians and lower Gnathostomes in general . He participated in

208-433: Is now rarely done, except in motion pictures. Even where black-and-white positives are currently used, the process to create them typically uses an internegative with standard processing instead of a chemical reversal process. Black-and-white reversal films are less common than color reversal films. Finished transparencies are most frequently displayed by projection. Some projectors use a sliding mechanism to manually pull

234-458: Is removed by washing and a clearing bath containing sodium metabisulfite or potassium metabisulfite . The remaining silver halide salts are re-exposed to light, developed and fixed, and the film is washed and dried. Black-and-white transparencies were once popular for presentation of lecture materials using 3¼"×4" (3¼" square in the UK) glass-mounted slides. Such positive black-and-white projection

260-402: Is sometimes used as motion picture film , mostly in the 16 mm , Super 8 and 8 mm "cine" formats , to yield a positive image on the camera original. This avoids the expense of using negative film, which requires additional film and processing to create a positive film print for projection. The earliest practical and commercially successful color photography reversal process

286-410: Is still occasionally used in a cladistic sense to denote labyrinthodonts more closely related to modern amphibians than to amniotes . Jarvik also studied the anatomy and relationships of lungfish which he held to be relatively primitive gnathostomes, possibly related to holocephalans, and of acanthodians , which he considered to be elasmobranchs rather than osteichthyans. He made contributions to

SECTION 10

#1732791707153

312-723: The Agfa color screen plates and films and Dufaycolor film, all of which were discontinued by 1961. Leopold Godowsky, Jr. and Leopold Mannes , working with the Eastman Kodak Company , developed Kodachrome , the first commercially successful color film to use the subtractive method. Kodachrome was introduced in 1935 as 16mm motion picture film , and in 1936 as 35mm film for still cameras. Kodachrome films contain no color dye couplers ; these are added during processing. The final development process published by Kodak as K-14 involves multiple re-exposure steps to sensitize

338-574: The Osteolepiformes and the Porolepiformes . He published several solidly descriptive works on Devonian sarcopterygians. After the death of Säve-Söderbergh, Jarvik was tasked with investigating and fully describing the anatomy of Ichthyostega . His work resulted in a 1996 monograph with an extensive photographic documentation of the material collected in 1929–1955. In particular, he conducted detailed anatomical studies of

364-723: The Greenland expedition of Gunnar Säve-Söderbergh in 1932 and was appointed assistant in the Department of Palaeozoology of the Swedish Museum of Natural History in Stockholm in 1937; he eventually succeeded Erik Stensiö as professor and head of the department in 1960, retiring in 1972. Jarvik's research concerned mainly the sarcopterygian fishes. His main interests were in the so-called "rhipidistian" sarcopterygian fishes, which he held to be divided into two groups:

390-618: The Nicotine Patch Jarvik , a 2019 short film by Emilie Mannering [REDACTED] Surname list This page lists people with the surname Jarvik . If an internal link intending to refer to a specific person led you to this page, you may wish to change that link by adding the person's given name (s) to the link. Retrieved from " https://en.wikipedia.org/w/index.php?title=Jarvik&oldid=1184621299 " Category : Surnames Hidden categories: Articles with short description Short description

416-713: The basis of his findings, he argued that Amphibia should be split, with salamanders (and possibly caecilians) in one class (the Urodelomorpha ), and the frogs as a separate class, the Batrachomorpha . The Lepospondyli were considered to be possible urodelomorphans, while the " labyrinthodonts " were thought to be batrachomorphs. Jarvik's ideas was never widely accepted, though Friedrich von Huene did include his system in systematic treatment of tetrapods. Few other supported his ideas, and today it has been abandoned by vertebrate paleontologists. The term "Batrachomorpha"

442-406: The cost of projection equipment and slide film was offset by not having to pay for prints. Eventually, print quality improved and prices decreased, and, by the 1970s, color negative film and color prints had largely displaced slides as the primary method of amateur photography. Until about 1995, color transparency was preferred for publication because of the films' higher contrast and resolution, and

468-426: The cranium of Eusthenopteron foordi using a serial-section technique introduced by William Johnson Sollas and applied to fossil fishes by Erik Stensiö . A fossil of limited external quality was sectioned by grinding off a thin section, photographing the grind-off end and repeat the process until the whole fossil was worked through. The internal structures would then show up on long series of photographs. Working in

494-404: The day before computer simulations, models were made by projecting reversal film on a board, and cut thin wax plates to match. The sticky wax plates could then be assembled to a three-dimensional scaled-up model of the skull, complete with internal structures such as nerve channels and other internal hollows rarely seen in fossils. Further section to the cranium could easily be made by cutting

520-523: The transition from fishes to tetrapods. Jarvik was a member of the Royal Swedish Academy of Sciences and French Academy of Sciences and Knight of the Order of Vasa . The lungfish Jarvikia and the osteolepiform Jarvikina are named after him. Reversal film In photography , reversal film or slide film is a type of photographic film that produces a positive image on

546-428: The transparency out of the side of the machine, where it is replaced by the next image. Modern, advanced projectors typically use a carousel that holds a large number of slides; a mechanism automatically pulls a single slide from the carousel and places it in front of the lamp. Small externally lit or battery-powered magnifying viewers are available. In traditional newsrooms and magazine offices slides were viewed using

SECTION 20

#1732791707153

572-596: The unsensitized grains. In late 1936, Agfacolor Neu was launched, Agfa having overcome earlier difficulties with color sensitivity problems. This film had the dye couplers incorporated into the emulsion, making processing simpler than for Kodachrome. Early color negative film had many shortcomings, including the high cost of the film, processing and printing, the mediocre color quality, rapid fading and discoloration of highlights of some types of print that became noticeable after several years. Amateurs who owned projection equipment used reversal films extensively because

598-405: The wax model at the desired angle. Due to the sticky nature of the wax used, a sectioned skull was put back together by simply pressing the two sections back together. This technique was also applied to the cranium of the porolepiform Glyptolepis groenlandica . Jarvik was deeply involved in the debate over the principal structure and homology of the vertebrate head, and he was responsible for

624-437: Was packaged in cassettes like normal 35mm film. A separate processing unit was used to develop it after exposure. Black-and-white transparencies can be made directly with some modern black-and-white films, which normally yield negatives. The negative image is developed but not fixed. The negative image is removed by bleaching with a solution of potassium permanganate or potassium dichromate in dilute sulfuric acid , which

650-484: Was the Lumière Autochrome , introduced in 1907. It was an additive method, using a panchromatic emulsion coated on a thin glass plate previously coated with a layer of dyed potato starch grains. Autochrome plates were discontinued in the 1930s, after the introduction of Lumière Filmcolor in sheet film and Lumicolor in roll film sizes. Also using the additive principle and reversal processing were

676-530: Was widely used in commercial and advertising photography, reportage, sports, stock and nature photography. Digital media gradually replaced transparency film. All color reversal film sold today is developed with the E-6 process . The non-substantive Kodachrome films, the last of which was discontinued in 2009, were processed with the K-14 process . Polaroid produced an instant slide film called Polachrome . It

#152847