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Schmidt–Cassegrain telescope

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The Schmidt–Cassegrain is a catadioptric telescope that combines a Cassegrain reflector 's optical path with a Schmidt corrector plate to make a compact astronomical instrument that uses simple spherical surfaces .

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59-546: The American astronomer and lens designer James Gilbert Baker first proposed a Cassegrain design for Bernhard Schmidt 's Schmidt camera in 1940. The optical shop at Mount Wilson Observatory manufactured the first one during World War II as part of their research into optical designs for the military. As in the Schmidt camera , this design uses a spherical primary mirror and a Schmidt corrector plate to correct for spherical aberration . In this Cassegrain configuration

118-626: A B.A. in 1935. He met his future wife, Elizabeth Katherine Breitenstein, while at the university. Pursuing his interest in astronomy, he studied at the Harvard College Observatory . He earned his M.A. in 1936, gained an appointment as a Junior Fellow of the Harvard Society from 1937 until 1943. It was in 1940 that he developed the Baker-Schmidt telescope, a modification of the schmidt camera . In 1942 he

177-483: A Blue Ribbon School, the highest honor the department can bestow on a school. The school earned a Blue Ribbon award again in 2020. Many interior shots of the 1999 film The Insider were filmed at Manual. Dr. Jeffrey Wigand , the subject of the film, taught science and Japanese at Manual after he was fired by tobacco company Brown & Williamson in 1993. Manual classrooms and offices are located in three buildings spread over two city blocks. The main building

236-461: A Manual graduate who was on the 1993 and 1994 teams, was the 1994 Teen Champion on Jeopardy! . Three other Manual students have competed on Jeopardy! . Manual's academic teams have also won both National Science Bowl and National Academic League championships, and achieved 7th place at the NAQT 's High School National Championships. Manual has a history of one of the top policy debate programs in

295-432: A costume shop and an 886-seat proscenium -style theater. The YPAS building did not contain extensive classroom space, however, and for many years teachers conducted YPAS classes in hallways and on loading docks if other space wasn't available. Since 1993, YPAS has used an adjacent facility, built in 1899 and formerly home to Cochran Elementary, as an annex. Manual focused on industrial training early in its history, but by

354-427: A decline in discipline and test scores in the 1970s. In 1984, Manual became a magnet school , allowing students from throughout the district to apply to five specialized programs of study, or magnets. Manual and Male High School have the oldest football rivalry in the state, dating back to 1893. Manual's football team has won five state titles and claims two national championships. In the 1980s and 1990s Manual became

413-521: A flatter field than most compact designs, but at the expense of longer tube length. The Schmidt–Cassegrain design is very popular with consumer telescope manufacturers because it combines easy-to-manufacture spherical optical surfaces to create an instrument with the long focal length of a refracting telescope with the lower cost per aperture of a reflecting telescope . The compact design makes it very portable for its given aperture, which adds to its marketability. Their high f-ratio means they are not

472-522: A half-block from Manual's main building, which includes classrooms, production facilities, a costume shop and an 886-seat proscenium -style theater. Since 1993, YPAS has used an adjacent facility, built in 1899 and formerly home to Cochran Elementary, as an annex. YPAS is one of Manual's magnet programs and YPAS students take their academic classes at Manual and must complete the same academic requirements as any public school student in Kentucky. Unlike

531-477: A home for two of the university's women's athletic teams. In the 1980s, the U of L women's basketball team used Manual's gym as a part-time home, playing a total of 40 games in eight seasons there. The U of L volleyball team used the Manual gym as its primary home from 1977 through 1990, after which the team moved into the newly built Cardinal Arena on its own campus. In 1992, Manual began a $ 3.5 million renovation of

590-476: A location at Fifth and Hill Streets. It changed its name to Louisville Girls High School in 1911. In 1934, the school moved into Reuben Post Halleck Hall, which had just been completed. The building was initially home to the Girls High School on the second and third floors, and Louisville Junior High School on the first. Over 12,000 women graduated from the school in its 94 years of operation. By

649-420: A mixed reaction, especially as most freshmen and sophomores were to be transferred to other schools. One critic in the black community called the plan "one-way busing". A few days after the proposal was announced, about 300 students walked out of class at Manual and marched to Central High School , where most of them were being transferred, in protest. The protest succeeded in persuading the school board to modify

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708-462: A plan to merge Manual and its rival Male High School into Louisville Boys High so that the two schools could share a new $ 300,000 facility. The plan took effect in 1915. Industrial training classes continued at the old Manual building. Parents objected to their children having to travel between the two buildings and the consolidation did not save the school board any money, so they voted to end the experiment in 1919. The new building became Male's home for

767-492: A prominent academic school and has been included several times in lists of America's top high schools in Redbook and Newsweek magazines. The high school has been recognized as a Perennial Top Academic School in Kentucky and holds the most national merit semi-finalists among all JCPS High Schools. In 1892, Louisville factory owner Alfred Victor du Pont donated $ 150,000 to the board of Louisville Public Schools to establish

826-465: A running track and various athletic fields. The project doubled Manual's campus to its modern size of 17 acres (69,000 m ). This was a part of a larger city-funded effort which created Noe Middle School north of Manual and increased the size of the University of Louisville campus, which was originally touted as a plan to create a continuous chain of schools over many blocks. Manual even became

885-438: A secondary with a focal ratio also around f/2, the separation of the two mirrors determining a typical system focal ratio around f/10. One very well-corrected type of non-compact design is the concentric (or monocentric) Schmidt–Cassegrain, where all the mirror surfaces and the focal surface are concentric to a single point: the center of curvature of the primary. Optically, non-compact designs give better aberration correction and

944-540: A traditional college preparatory curriculum with electives. The Math/Science/Technology (MST) magnet specifically prepares students for college programs in engineering, science and math. Minimal requirements for MST students include courses in algebra , trigonometry , calculus (including mandatory AP Calculus ), biology , chemistry and computer programming . The Journalism & Communication (J&C) magnet focuses on journalism, publishing, and media production. To earn class credit, J&C students can participate in

1003-530: A training school to teach young men industrial arts ("manual") skills that would fit them for their duties in life. The Victorian building was built on the corner of Brook and Oak Streets by the firm of Clark and Loomis, which also designed the Speed Art Museum and Waverly Hills Sanatorium . After Manual moved out of the building it was used as a Middle School until 1974 when it was converted to apartments. Manual's first principal, Henry Kleinschmid,

1062-404: A wide-field telescope like their Schmidt camera predecessor, but they are good for more narrow-field deep sky and planetary viewing. Consumer version of this design typically achieve focus by adjusting the position of the primary mirror rather than a traditional eye-piece. This means that small changes in the position of the mirror are magnified by the focal length of the telescope. As the mirror

1121-653: Is a public magnet high school located in the Old Louisville neighborhood of Louisville, Kentucky , United States. It serves students in grades 9 – 12 . It is a part of the Jefferson County Public School District . DuPont Manual is recognized by the United States Department of Education as a Blue Ribbon School . Manual, funded by Mr. A.V duPont, opened in 1892 as an all-male manual training school. It

1180-586: Is also considered. The acceptance rate to each magnet varies with the number of applicants in any given year; in the mid-1990s about a third of applicants to these three magnets were selected each year. Admission the other two magnets, Visual Arts and the Youth Performing Arts School, are decided based primarily on auditions. The Visual Arts magnet is located in a wing of art classrooms and features an art show each year for graduating seniors. The Visual Arts magnet provides students with

1239-425: Is located at or near the focus of the primary mirror. In the non-compact, the corrector plate remains at or near the center of curvature (twice the focal length ) of the primary mirror. Compact designs combine a fast primary mirror and a small, strongly curved secondary. This yields a very short tube length, at the expense of field curvature. Compact designs have a primary mirror with a focal ratio of around f/2 and

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1298-447: Is not permanently fixed in place, it is possible for it to move by a small amount and cause the image to shift. This is otherwise known as "mirror flop". Some Schmidt-Cassegrain telescopes are equipped with mirror locks to fix the primary mirror in place once focus has been achieved. James Gilbert Baker James Gilbert Baker (November 11, 1914 – June 29, 2005) was an American astronomer and designer of optics systems. He

1357-554: The James Gregory Telescope is also recognized as the largest Schmidt-Cassegrain. The telescope is noted for its large field of view, up 60 times a full moon. While there are many variations of the Schmidt–Cassegrain telescope design (both mirrors spherical, both mirrors aspherical , or one of each), they can be divided into two principal types: compact and non-compact. In the compact form, the corrector plate

1416-737: The Perkin Elmer Corporation . Following the war he then became an advisor for the Air Force Photographic Laboratory. Living in Cambridge, Massachusetts , from 1946 until 1949 he was an associate professor at Harvard University, as well as continuing his research into optics he had pursued during the war. In 1948 he moved to Orinda, California to join the Lick Observatory as a research associate. He returned to Harvard in 1950. Prior to

1475-587: The University of Louisville , which is located directly south of Manual. In 2000, Manual implemented block scheduling, which allowed students to take eight classes per year, which are scheduled four per day on alternating days. Since 2000, Manual has held Kentucky's state record of 52 National Merit Semifinalists , ranking third in the United States for that year. Manual's academic team won state titles at Governor's Cup, Kentucky's top high school academic competition, in 1993, 1994, 2005, and 2013. Matt Morris,

1534-406: The convex secondary mirror acts as a field flattener and relays the image through the perforated primary mirror to a final focal plane located behind the primary. Some designs include additional optical elements (such as field flatteners) near the focal plane. The first large telescope to use the design was the James Gregory Telescope of 1962 at the University of St Andrews . As of 2021,

1593-496: The 1920s, beating Male two years in a row for the first time in its history. Manual shared athletic facilities with Male for many years, but in the early 1920s alumni raised funds to construct Manual Stadium. The stadium opened in 1924 with 14,021 permanent seats. It was one of the largest high school stadiums in America at the time. The original structure was condemned and closed in 1952 after years of heavy use and minimal upkeep, and

1652-577: The 1940s, budget concerns and national trends made it clear that Louisville Girls High School and duPont Manual would merge into one coeducational school. They finally did so in September 1950 and remained in the old Louisville Girls High School building. This fusion of institutions resulted in the birth of the modern duPont Manual High School – dropping 'Training' from its previous name. The same school building remains in use today, although two major additions have since been made. The middle school located on

1711-399: The 1971–72 school year, necessitating 17 portable classrooms in the front and rear courtyards. Manual still had grades seven through twelve at this time, and overcrowding gradually began to improve after Manual dropped the seventh and eight grades when Noe Middle School opened in 1974. Throughout the decade the administration gradually dropped the last vestiges of its manual training emphasis as

1770-558: The Large Varsity Division, and in 2003 and 2006 they won the Medium Varsity Division title. Varsity boys' soccer was second at states in 2005 and third in 2004. In 2006, the Manual girls' cross country team won the school's first team title after placing second in 2004 and 2005. The 2006 win was the first championship for a Jefferson County, Kentucky Class AAA Public School since 1980. In 2007,

1829-560: The Manual boys' cross country team also won a Class AAA state championship. The swim team maintained state titles from 2003 to 2008. From 2004 through 2008, Manual won the Combined Girls' and Boys' State Championship, and the girls maintained their own state championship from 2005 through 2008. The boys' tennis team achieved their best finish at the KHSAA State Tennis Tournament in 2008 by winning

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1888-425: The United States as economically advantaged families moved towards Louisville's suburbs. Manual was exempt from court-ordered busing in the 1970s because its racial makeup already met federal guidelines. On November 11, 1976, what school board members referred to as a race-related riot occurred on campus, injuring 16 and leading to six arrests and 60 suspensions. Students and school administrators agreed that there

1947-504: The all-male Mitre Club, persisted into the 1950s as unofficial organizations but gradually faded away. Students began publishing a newspaper, The Crimson Record , in 1955. Following the Brown v. Board of Education Supreme Court decision, Manual became racially integrated without controversy in 1956 and graduated its first two black students in 1958. Starting in the 1960s, Manual began to face problems associated with inner city schools in

2006-413: The building's first floor became Manly Junior High and moved to Manual's old building at Brook and Oak. The merged school began developing traditions such as Homecoming in 1951, and Red and White Day in 1953. Red and White Day eventually became a full week of school spirit related activities preceding the annual Male-Manual football game. Two traditions of the sexually segregated past, sororities and

2065-478: The creation of the school's national award-winning publications and productions: yearbook ( The Crimson ), a city-wide youth newsmagazine ( On the Record ), literary magazine ( One Blue Wall ), a school news website ( RedEye ) and a daily morning television show called CSPN-TV, which is streamed online and broadcast to classrooms. The J&C program was formerly known as CMA (Communications and Media Arts), but

2124-1023: The distinction of being the high school that sent the most students to the INTEL International Science and Engineering Fair (ISEF). In 2022, duPont Manual was ranked #47 in the National Rankings, #1 in Kentucky High Schools, #1 in Louisville, KY Metro Area High Schools, and #1 in Jefferson County Public Schools High Schools. The Youth Performing Arts School (YPAS) is one of only two programs in Kentucky allowing high school students to major in performing arts . Between 1995 and 2005, 90% of YPAS students received college scholarships totaling an average of over one million dollars per year. YPAS has its own building

2183-871: The district for their backgrounds in the arts. The YPAS choir was the only chorus to perform at the January 2001 inauguration of President George W. Bush . John Reccius , an early Major League Baseball player, organized Manual's first baseball team in 1900. An early baseball star was Ferdie Schupp , who would go on to pitch in the 1917 World Series , but left Manual two months before graduating. Manual claims seven "mythical" state baseball championships and has won six official ones, most recently in 1962. A total of ten Manual players have played in Major League Baseball, most notably Pee Wee Reese . The varsity cheerleaders have won several NCA National Championship titles. In 1997, 1998, 2004, and 2005, they won

2242-458: The first ever regional tournament in Manual history. The state team won the state title in 2008, making Manual the second public school to ever win the title. The boys' bowling team won the state title in 2010. The school also offers basketball , dance (called the Dazzlers), field hockey , golf , lacrosse , and volleyball , among other sports teams. The varsity field hockey team won

2301-410: The late 1970s it had a standard curriculum. In 1980, Iowa Test of Basic Skills scores ranked Manual 23rd out of the 24 high schools in the county. Under principal Joe Liedtke, academics improved, especially after Manual became a magnet school in 1984 and could attract students from throughout the county. All students enroll in one of five magnet programs. The High School University (HSU) magnet offers

2360-633: The launch of the Sputnik I spacecraft, Baker collaborated with Joseph Nunn to build a series of 12 satellite tracking cameras that would be called the Baker-Nunn camera . Dr. Baker designed the optical system for the cameras, which were fabricated by Perkin-Elmer Corporation. He and Edwin Land were instrumental in persuading President Dwight Eisenhower to have the U-2 spy plane built. Baker also designed

2419-727: The lenses and most of the cameras used on the U-2 spy plane and later the SR-71 Blackbird . In addition, he designed the lenses and cameras used in the Samos satellite program , and a modified version of these optics were later used in the lunar mapping programs. During the 1960s he designed the folding optics for the Polaroid SX-70 Land Camera . He also designed the Baker Super-Schmidt camera, which

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2478-488: The main building which included a new roof and a glass-enclosed cafeteria for juniors and seniors. The Youth Performing Arts School has its own building a half-block from Manual's main building. It was completed in 1978 at a cost of $ 1.5 million as the final stage of the same plan that expanded Manual's campus and built Noe. Noe had been built without an auditorium in anticipation of a theater-oriented school being built on site. The YPAS building includes production facilities,

2537-586: The name was changed so that the Manual program's specific emphasis on journalism would be reflected in the name, distinguishing the magnet from others in the district with similar names. Admission to the HSU, MST and J&C magnets are decided by a committee of Manual teachers based on academic performance as measured by prior school grades and the Commonwealth Accountability Testing System , although extracurricular involvement

2596-497: The next 70 years and Manual returned to its old building at Brook and Oak. In 1923 an expansion added new laboratories, a cafeteria, and the largest gym ever built in Louisville at the time. The addition eventually burned and had to be destroyed in 1991. Manual's enrollment numbers, which had hovered around 400 since the 1890s, soared from 429 in 1919 to 1,039 in 1925. The Manual Crimsons football team, which had also been consolidated with Male's from 1915 to 1918, had great success in

2655-458: The number of shop classes dwindled from 16 in 1971 to three in 1979. The Youth Performing Arts School , actually a magnet school within Manual, opened in 1978 and, along with the changing curriculum, presaged Manual's transition to an academically intensive magnet school in the 1980s. Manual became a magnet school in 1984, creating specialty programs and allowing students from around the district to apply to attend. The change initially met with

2714-472: The opportunity to work with a variety of media, including clay/sculpture, fibers, printmaking, painting, drawing and graphic design. The Math/Science/Technology program and the Youth Performing Arts School have achieved national recognition on multiple occasions. In 1994, Manual began offering Advanced Placement (AP) courses. In 2001 it offered 45 AP courses, more than any other school in the state. Qualifying students may take college courses free of charge at

2773-460: The other magnets, YPAS is semi-autonomous; it has its own assistant principals, counselor, administrative staff, and parents' organization. Many Manual students take classes at YPAS, even if it is not their academic major . Students at YPAS major in vocal music , instrumental music ( band , orchestra , piano , or guitar ), dance , theater , design and production , or musical theatre . YPAS instructors are school teachers recruited from around

2832-423: The proposal to exclude sophomores from being transferred. The magnet programs succeeded in attracting applicants and by the mid-1990s only about a third of students who applied were accepted. In the midst of the transition to magnet school, Manual underwent a $ 1.9 million building improvement plan which added computer and science labs. Also in 1991, the United States Department of Education recognized Manual as

2891-494: The school being viewed as blue-collar and academically inferior to Male High School in its early days, numerous early graduates went on to become medical doctors, and students published a literary magazine called The Crimson from 1899 to 1955. In order to accommodate newly added French and Latin classes, Manual was expanded to a four-year school in 1901. In 1911, Manual became the first school in Kentucky to serve lunches to students. In 1913, Louisville Public Schools announced

2950-681: The state. In the 1990s Manual students won the Jefferson County championships most years and qualified teams for the National Forensic League tournament and the TOC Tournament of Champions . Manual has been mentioned several times in lists of America's top high schools in Redbook and Newsweek magazines. In 2002, Manual was separated from the rest of the schools in its district and made to hold its own regional science fair . In 2015, duPont Manual had

3009-460: The team title. Previously, their best result had come in 2006 when they tied rival St. Xavier High School for second place. The boys' team also won the state doubles title in 2006, which was the first state title in Ram tennis history on the boys' side. The team had five consecutive runner up positions from the 2001—2002 year until the 2005—2006 year. In 2008, the Manual boys' tennis team went on to win

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3068-464: Was a favorite of du Pont but was unpopular with the school board, which conspired to replace him in 1895. Despite a summer of controversy and protest from the du Pont family, Manual's first two graduating classes and the four major local newspapers, the board replaced him with Harry Brownell on July 2. Manual was initially a three-year school with some general academic classes and an emphasis on mechanical and industrial training. Although graduates recall

3127-427: Was an atmosphere of racial tension brewing at Manual in the 1970s that led to the riot. In his 2005 book on the history of Manual, Mike McDaniel wrote that November 11, 1976 was "quite probably the worst day in the history of Manual." The late 1960s and 1970s were a time of major change at Manual. A new wing featuring a gym with a seating capacity of 2,566 opened in 1971. The school had as many as 3,360 students in

3186-455: Was awarded his PhD in astronomy and astrophysics from Harvard University . After the start of World War II , he was recruited to be a civilian optical designer for the Army's newly formed aerial reconnaissance branch under Colonel George William Goddard . He would design wide-angle camera systems and test them in unpressurized compartments during test flights. He also became a consultant for

3245-551: Was born in Louisville, Kentucky to Jesse B. Baker and Hattie M. Stallard, the fourth child of that couple. He attended Louisville duPont Manual High School then majored in mathematics at the University of Louisville . During his time at the university, he became interested in astronomy and grinding his own mirrors. In 1931 he helped to form the Louisville Astronomical Society . He graduated with

3304-509: Was originally called Reuben Post Halleck Hall and was home to the Louisville Girls High School before it merged with Manual. The Gothic-style building was completed in 1934 at a cost of $ 1.1 million. The 9-acre (36,000 m ) tract it was built on had previously been the site of the old Masonic Widows and Orphans Home. In 1967 an urban renewal program demolished a residential block east of the main building to create

3363-485: Was reopened after being rebuilt in 1954. Its modern capacity is 11,463. The Louisville Girls High School opened as Female High School in 1856 at what became the intersection of Armory Place and Muhammad Ali Boulevard. It was the female counterpart to Male High School, also opened in 1856, and they were the first two public high schools in Louisville. Female High School moved to a location on First Street north of Chestnut in 1864 and remained there until 1899 when it moved to

3422-456: Was the second public high school in Louisville. Manual merged with its rival, Male High School , into a consolidated school from 1915 to 1919. Manual permanently merged with the Louisville Girls High School in 1950 and moved into their Gothic -style three-story building, built in 1934. In 2004, after conducting a poll, Louisville's Courier-Journal newspaper listed Manual as one of Louisville residents' ten favorite buildings. Manual experienced

3481-740: Was used to track meteors , and the Paul-Baker telescope . In 1960 he became president of the Optical Society of America . Baker was the author of many technical papers and he held more than 50 U.S. patents. He was the first person to use a computer for the design of optics . He died in Bedford, New Hampshire at the age of 90, and was survived by his wife Elizabeth, and his three sons, a daughter, and five grandchildren. (His children have also pursued technical careers). Louisville duPont Manual High School duPont Manual High School

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