vania-janet/multiturn-rag-retrieval-data huggingface dataset:
Chroma key
Some films make heavy use of chroma key to add backgrounds that are constructed entirely using computer - generated imagery ( CGI ) . Performances from different takes can be composited together , which allows actors to be filmed separately and then placed together in the same scene . Chroma key allows performers to appear to be in any location without leaving the studio . Computer development also made it easier to incorporate motion into composited shots , even when using handheld cameras . Reference - points can be placed onto the colored background ( usually as a painted grid , X 's marked with tape , or equally spaced tennis balls attached to the wall ) . In post-production , a computer can use the references to compute the camera 's position and thus render an image that matches the perspective and movement of the foreground perfectly . Modern advances in software and computational power have eliminated the need to accurately place the markers -- the software figures out their position in space ( a disadvantage of this is that it requires a large camera movement , possibly encouraging modern film techniques where the camera is always in motion ) .
Chroma key
Sometimes a shadow can be used to create a visual effect . Areas of the bluescreen or greenscreen with a shadow on them can be replaced with a darker version of the desired background video image , making it look like the person is casting a shadow on them . Any spill of the chroma key color will make the result look unnatural . A difference in the focal length of the lenses used can affect the success of chroma key .
Raising the Flag on Iwo Jima
Three Marines in the photograph , Sergeant Michael Strank , Corporal Harlon Block ( misidentified as Sergeant Hank Hansen until January 1947 ) , and Private First Class Franklin Sousley were killed in action over the next few days . The other three surviving flag - raisers in the photograph were Corporals ( then Private First Class ) Rene Gagnon , Ira Hayes , and Harold Schultz ( misidentified as PhM2c . John Bradley until June 2016 ) . Both men originally misidentified as flag raisers had helped raise a smaller flag about 90 minutes earlier , and were both still on the mountaintop and witnessed -- but were not part of -- the specific moment of raising the larger flag that was captured in the Pulitzer Prize - winning photo .
Mount Everest
In 2011 two Nepali paraglided from the Everest Summit to Namche in 42 minutes . They had run out of oxygen and supplies , so it was a very fast way off the mountain . The duo won National Geographic Adventurers of the Year for 2012 for their exploits . After the paraglide they kayaked to the Indian Ocean , and they had made it to the Bay of Bengal by the end of June 2011 . One had never climbed , and one had never para-glided , but together they accomplished a ground - breaking feat . By 2013 footage of the flight was shown on the television Nightline . ( see also kayaking for more on this style of activity )
Hot air balloon
Baskets may also be made of aluminium , especially a collapsible aluminium frame with a fabric skin , to reduce weight or increase portability . These may be used by pilots without a ground crew or who are attempting to set altitude , duration , or distance records . Other specialty baskets include the fully enclosed gondolas used for around - the - world attempts , and baskets that consist of little more than a seat for the pilot and perhaps one passenger .
Sundial
The uniformity of their spacing makes this type of sundial easy to construct . If the dial plate material is opaque , both sides of the equatorial dial must be marked , since the shadow will be cast from below in winter and from above in summer . With translucent dial plates ( e.g. glass ) the hour angles need only be marked on the sun - facing side , although the hour numberings ( if used ) need be made on both sides of the dial , owing to the differing hour schema on the sun - facing and sun - backing sides .
Kargil War
There was a surge in patriotism , with many celebrities expressing their support for the Kargil cause . Indians were angered by media reports of the death of pilot Ajay Ahuja , especially after Indian authorities reported that Ahuja had been murdered and his body mutilated by Pakistani troops . The war had produced higher than expected fatalities for the Indian military , with a sizeable percentage of them including newly commissioned officers . One month after conclusion of the Kargil War , the Atlantique Incident , in which a Pakistan Navy plane was shot down by India , briefly reignited fears of a conflict between the two countries .
Color motion picture film
The three color records are stacked as shown at right , with a UV filter on top to keep the non-visible ultraviolet radiation from exposing the silver - halide crystals , which are naturally sensitive to UV light . Next are the fast and slow blue - sensitive layers , which , when developed , form the latent image . When the exposed silver - halide crystal is developed , it is coupled with a dye grain of its complementary color . This forms a dye `` cloud '' ( like a drop of water on a paper towel ) and is limited in its growth by development - inhibitor - releasing ( DIR ) couplers , which also serve to refine the sharpness of the processed image by limiting the size of the dye clouds . The dye clouds formed in the blue layer are actually yellow ( the opposite or complementary color to blue ) . There are two layers to each color ; a `` fast '' and a `` slow . '' The fast layer features larger grains that are more sensitive to light than the slow layer , which has finer grain and is less sensitive to light . Silver - halide crystals are naturally sensitive to blue light , so the blue layers are on the top of the film and they are followed immediately by a yellow filter , which stops any more blue light from passing through to the green and red layers and biasing those crystals with extra blue exposure . Next are the red - sensitive record ( which forms cyan dyes when developed ) ; and , at the bottom , the green - sensitive record , which forms magenta dyes when developed . Each color is separated by a gelatin layer that prevents silver development in one record from causing unwanted dye formation in another . On the back of the film base is an anti-halation layer that absorbs light which would otherwise be weakly reflected back through the film by that surface and create halos of light around bright features in the image . In color film , this backing is `` rem - jet '' , a black - pigmented , non-gelatin layer which is removed in the developing process .
Rotation
Principal rotations have the advantage of modelling a number of physical systems such as gimbals , and joysticks , so are easily visualised , and are a very compact way of storing a rotation . But they are difficult to use in calculations as even simple operations like combining rotations are expensive to do , and suffer from a form of gimbal lock where the angles can not be uniquely calculated for certain rotations .
Red vs. Blue
Episodes that have been made with Halo 3 have used the theater mode camera . Starting in season 8 , action sequences have been made with fully scripted fight scenes that involve stunts not possible with the previous game engine .
Binary star
This method of detecting binaries is also used to locate extrasolar planets orbiting a star . However , the requirements to perform this measurement are very exacting , due to the great difference in the mass ratio , and the typically long period of the planet 's orbit . Detection of position shifts of a star is a very exacting science , and it is difficult to achieve the necessary precision . Space telescopes can avoid the blurring effect of Earth 's atmosphere , resulting in more precise resolution .
Red-tailed hawk
Because they are so common and easily trained as capable hunters , the majority of hawks captured for falconry in the United States are red - tails . Falconers are permitted to take only passage hawks ( which have left the nest , are on their own , but are less than a year old ) so as to not affect the breeding population . Adults , which may be breeding or rearing chicks , may not be taken for falconry purposes and it is illegal to do so . Passage red - tailed hawks are also preferred by falconers because these younger birds have not yet developed the adult behaviors which would make them more difficult to train .
Kargil War
Kargil was targeted partly because the terrain was conducive to the preemptive seizure of several unoccupied military positions . With tactically vital features and well - prepared defensive posts atop the peaks , a defender on the high ground would enjoy advantages akin to a fortress . Any attack to dislodge a defender from high ground in mountain warfare requires a far higher ratio of attackers to defenders , and the difficulties would be exacerbated by the high altitude and freezing temperatures .
Rainbow
In theory , every rainbow is a circle , but from the ground , only its upper half can be seen . Since the rainbow 's centre is diametrically opposed to the sun 's position in the sky , more of the circle comes into view as the sun approaches the horizon , meaning that the largest section of the circle normally seen is about 50 % during sunset or sunrise . Viewing the rainbow 's lower half requires the presence of water droplets below the observer 's horizon , as well as sunlight that is able to reach them . These requirements are not usually met when the viewer is at ground level , either because droplets are absent in the required position , or because the sunlight is obstructed by the landscape behind the observer . From a high viewpoint such as a high building or an aircraft , however , the requirements can be met and the full - circle rainbow can be seen . Like a partial rainbow , the circular rainbow can have a secondary bow or supernumerary bows as well . It is possible to produce the full circle when standing on the ground , for example by spraying a water mist from a garden hose while facing away from the sun .
4K resolution
Though experiencing rapid price drops beginning in 2013 for viewing devices , the home cinema digital video projector market saw little expansion , with only a few manufacturers ( only Sony as of 2015 ) offering limited 4K - capable lineups , with native 4K projectors commanding five - figure price tags well into 2015 before finally breaking the US $10,000 barrier . Critics state that at normal direct - view panel size and viewing distances , the extra pixels of 4K are redundant at the ability of normal human vision . Projection home cinemas , on the other hand , employ much larger screen sizes without necessarily increasing viewing distance to scale . JVC has used a technique known as `` e-shift '' to extrapolate extra pixels from 1080p sources to display 4K on screens through upscaling or from native 4K sources at a much lower price than native 4K projectors . This technology of non-native 4K entered its fourth generation for 2016 . JVC used this same technology to provide 8K flight simulation for Boeing that met the limits of 20 / 25 visual acuity .
Grand Canyon
Aside from casual sightseeing from the South Rim ( averaging 7,000 feet ( 2,100 m ) above sea level ) , skydiving , rafting , hiking , running , and helicopter tours are popular . The Grand Canyon Ultra Marathon is a 78 - mile ( 126 km ) race over 24 hours . The floor of the valley is accessible by foot , muleback , or by boat or raft from upriver . Hiking down to the river and back up to the rim in one day is discouraged by park officials because of the distance , steep and rocky trails , change in elevation , and danger of heat exhaustion from the much higher temperatures at the bottom . Rescues are required annually of unsuccessful rim - to - river - to - rim travelers . Nevertheless , hundreds of fit and experienced hikers complete the trip every year .
Atomic bombings of Hiroshima and Nagasaki
After exceeding the original departure time limit by nearly a half - hour , Bockscar , accompanied by The Great Artiste , proceeded to Kokura , thirty minutes away . The delay at the rendezvous had resulted in clouds and drifting smoke over Kokura from fires started by a major firebombing raid by 224 B - 29s on nearby Yahata the previous day . Additionally , the Yawata Steel Works intentionally burned coal tar , to produce black smoke . The clouds and smoke resulted in 70 % of the area over Kokura being covered , obscuring the aiming point . Three bomb runs were made over the next 50 minutes , burning fuel and exposing the aircraft repeatedly to the heavy defenses around Kokura , but the bombardier was unable to drop visually . By the time of the third bomb run , Japanese antiaircraft fire was getting close , and Second Lieutenant Jacob Beser , who was monitoring Japanese communications , reported activity on the Japanese fighter direction radio bands .
Missile gap
Promotion of the missile gap had several unintended consequences . The R - 7 requires as much as 20 hours to be readied for launch so they could be easily attacked by bombers before they could strike . That demanded them be based in secret locations to prevent a pre-emptive strike on them . As Corona could find the sites no matter where they were located , the Soviets decided not to build large numbers of R - 7s and preferred more - advanced missiles that could be launched more quickly .
Red-tailed hawk
The red - tailed hawk commonly employs one of two hunting techniques . Often , they scan for prey activity from an elevated perch site , swooping down from the perch to seize the prey . They also watch for prey while flying , either capturing a bird in flight or pursuing prey on the ground until they can pin them down in their talons . Red - tailed hawks , like some other raptors , have been observed to hunt in pairs . This may consist of stalking opposites sides of a tree , in order to surround a tree squirrel and almost inevitably drive the rodent to be captured by one after being flushed by the other hawk . They are opportunistically attracted to conspicuous meals , such as displaying male red - winged blackbirds . Juvenile
Red-eye effect
If direct flash must be used , a good rule of thumb is to separate the flash from the lens by 1 / 20 of the distance of the camera to the subject . For example , if the subject is 2 meters ( 6 feet ) away , the flash head should be at least 10 cm ( 4 inches ) away from the lens .
War of the Worlds (2005 film)
The design of the Tripods was described by Spielberg as `` graceful , '' with artist Doug Chiang replicating aquatic life forms . At the same time , the director wanted a design that would be iconic while still providing a tribute to the original Tripods , as well as intimidating so the audience would not be more interested about the aliens inside than on the vehicle itself . The visual effects crew tried to blend organic and mechanical elements in the Tripods depiction , and made extensive studies for the movements of the vehicle to be believable , considering the `` contradiction '' of having a large tank - like head being carried by thin and flexible legs . Animator Randal M. Dutra considered the movements themselves to have a `` terrestrial buoyance '' , in that they were walking on land but had an aquatic flow , and Spielberg described the Tripods as moving like `` scary ballet dancers '' . Most of the alien elements revolved around the number three -- the Tripod had three eyes , and both the vehicle and the aliens had three main limbs with three fingers each . Visual effects supervisor Pablo Helman considered depicting the scale of the Tripod as challenging , considering `` Steven wanted to make sure that these creatures were 150 feet tall '' , as it was the height described by Wells in the novel . The aliens themselves had designs based on jellyfish , with movements inspired by red - eyed tree frogs , and an amphibian quality particularly on the wet skin . A styrofoam alien was used as a stand - in to guide the actors in the basement scene . Spielberg did not want any blood or gore during the Heat - Ray deaths ; in the words of Helman , `` this was going to be a horror movie for kids '' . So the effects crew came up with the vaporization of the bodies , and considering it could not be fully digital due to both the complexity of the effect and the schedule , live - action dust was used alongside the CGI ray assimilation and particles . Digital birds followed the Tripods in most scenes to symbolize the presence of death , which Chiang compared to vultures and added that `` you do n't know if these birds are going to the danger or away from it , if you should follow them or run away . ''
Indiana Jones and the Last Crusade
The tank broke down twice . The distributor 's rotor arm broke and a replacement had to be sourced from Madrid . Then two of the device 's valves used to cool the oil exploded , due to solder melting and mixing with the oil . It was very hot in the tank , despite the installation of ten fans , and the lack of suspension meant the driver was unable to stop shaking during filming breaks . The tank only moved at 10 to 12 miles per hour ( 16 to 19 km / h ) , which Vic Armstrong said made it difficult to film Indiana riding a horse against the tank while making it appear faster . A smaller section of the tank 's top made from aluminum and which used rubber tracks was used for close - ups . It was built from a searchlight trailer , weighed eight tons , and was towed by a four - wheel drive truck . It had safety nets on each end to prevent injury to those falling off . A quarter - scale model by Gibbs was driven over a 50 - foot ( 15 m ) cliff on location ; Industrial Light & Magic created further shots of the tank 's destruction with models and miniatures .
Fuel cell
Fuel cell - powered unmanned aerial vehicles ( UAV ) include a Horizon fuel cell UAV that set the record distance flown for a small UAV in 2007 . The military is interested in this application because of its low noise , low thermal signature and ability to attain high altitude . In 2009 the Naval Research Laboratory 's ( NRL 's ) Ion Tiger utilized a hydrogen - powered fuel cell and flew for 23 hours and 17 minutes . Fuel cells are also in use to provide auxiliary power in aircraft , replacing fossil fuel generators that were previously used to start the engines and power on board electrical needs .
Sundial
Because of the complexity of the above calculations , using them for the practical purpose of designing a dial of this type is difficult and prone to error . It has been suggested that it is better to locate the hour lines empirically , marking the positions of the shadow of a style on a real sundial at hourly intervals as shown by a clock . See Empirical hour - line marking , above .
Final Fantasy VII
The transition from 2D graphics to 3D environments overlaid on pre-rendered backgrounds was accompanied by a focus on a more realistic presentation . In previous entries , the sizes for characters and environments were fixed , and the player saw things from a scrolling perspective . This changed with Final Fantasy VII ; environments shifted with camera angles , and character model sizes shifted depending on both their place in the environment and their distance from the camera , giving a sense of scale . The choice of this highly cinematic style of storytelling , contrasting directly with Square 's previous games , was attributed to Kitase , who was a fan of films and had an interest in the parallels between film and video game narrative . Character movement during in - game events was done by the character designers in the planning group . While designers normally cooperate with a motion specialist for such animations , the designers taught themselves motion work , resulting in each character 's movements differing depending on their creators -- some designers liked exaggerated movements , while others went for subtlety . Much of the time was spent on each character 's day - to - day , routine animations . Motion specialists were brought in for the game 's battle animations . The first characters the team worked with were Cloud and Barret . Some of the real - time effects , such as an explosion near the opening , were hand - drawn rather than computer animated .
Edward O'Hare
Equipped with the highly successful follow - on to the Wildcat , the new Grumman F6F - 3 Hellcat , two - thirds of VF - 6 ( twenty - four F6F - 3s ) under Butch O'Hare's command embarked on August 22 , 1943 on the light carrier USS Independence ( CVL - 22 ) . The arrival of the F6Fs with their powerful Pratt & Whitney R - 2800 radial engines in late 1943 combined with the deployment of the new Essex class carriers and the Independence class carriers immediately gave the U.S. Pacific Fleet air supremacy wherever the Fast Carrier Force operated . The Hellcat 's first combat mission occurred on August 31 , 1943 , in a strike against Marcus Island . The F6F did well against Japanese fighters , and proved that with the right tactics and teamwork the Japanese Zero need not be considered a superior enemy . VF - 6 's combat debut on the Independence also went reasonably well . For his actions in battles near Marcus Island on August 31 , 1943 , O'Hare was awarded the Distinguished Flying Cross . For his actions in subsequent missions near Wake Island on October 5 , 1943 , O'Hare was awarded a Gold Star in lieu of a second Distinguished Flying Cross . A
Sound barrier
The British Air Ministry signed an agreement with the United States to exchange all its high - speed research , data and designs and Bell Aircraft company was given access to the drawings and research on the M. 52 , but the U.S. reneged on the agreement and no data was forthcoming in return . Bell 's supersonic design was still using a conventional tail and they were battling the problem of control . Chuck
Sound barrier
A huge number of advanced features were incorporated into the resulting M. 52 design , many of which hint at a detailed knowledge of supersonic aerodynamics . In particular , the design featured a conical nose and sharp wing leading edges , as it was known that round - nosed projectiles could not be stabilised at supersonic speeds . The design used very thin wings of biconvex section proposed by Jakob Ackeret for low drag . The wing tips were `` clipped '' to keep them clear of the conical shock wave generated by the nose of the aircraft . The fuselage had the minimum cross-section allowable around the centrifugal engine with fuel tanks in a saddle over the top . One
Color motion picture film
Fuji films also integrate tabular grains in their SUFG ( Super Unified Fine Grain ) films . In their case , the SUFG grain is not only tabular , it is hexagonal and consistent in shape throughout the emulsion layers . Like the T - grain , it has a larger surface area in a smaller grain ( about one - third the size of traditional grain ) for the same light sensitivity . In 2005 , Fuji unveiled their Eterna 500T stock , the first in a new line of advanced emulsions , with Super Nano - structure Σ Grain Technology .
Midnight sun
Observers at heights appreciably above sea level can experience extended periods of midnight sun as a result of the `` dip '' of the horizon viewed from altitude .
San Jose International Airport
In 2012 the airport had 134,947 aircraft operations , average 370 per day : 60 % airline , 16 % air taxi , 23 % general aviation and < 1 % military . 123 aircraft were then based at the airport : 49 % single - engine , 12 % multi-engine , 37 % jet and 2 % helicopter .
Chroma key
A newer technique is to use a retroreflective curtain in the background , along with a ring of bright LEDs around the camera lens . This requires no light to shine on the background other than the LEDs , which use an extremely small amount of power and space unlike big stage lights , and require no rigging . This advance was made possible by the invention in the 1990s of practical blue LEDs , which also allow for emerald green LEDs .