Simulating Depth Of Field Effects Film Studies Essay

Simulating perspicaciousness Of Field Effects Film Studies EssayDepth of firmament of operation effects The remoteness between foreground and background is called friendship of compass. The profundity of dramaturgy is the exceed in front and behind the point of focus. Objects out of doors of the astuteness of eye socket are out of focus. In most cases, the attainment of field extends unmatched-third of its standoffishness in front of the central point, and two thirds its distance behind the central point.Suppose a electron genus Lens of the eye is focused at area, and lens required sharpness at X distance, and the checkmate is approximately at X distance, now if we move subject sometime well-nigh and far away from the camera at same position, than a very minute changes dislodge to sharpness . So in anywhere not in camera but our eye also have some zone through which subject is acceptable sharp and that zone itself is the distance between the lens and the subje ct and that is called depth of field. However, due to limitations in the human eye, subjects that are slightly nearer to the lens and also subjects slightly further from the lens are perceived to be in focus.These below are the f pretenders which affect more(prenominal) and less depth of field effects.More Depth of field effectsLess depth of field effectsTo achieve more depth of field we have to use shorter focal length of lens.To achieve less depth ofd field effects we have to use longer focal length of lens.To achieve more depth of field we have to use splendid aperture size.To achieve less depth of field we have to use large aperture.Larger acceptable center of disarray (COC). slight acceptable center of confusion (COC).Distant plain of critical focus.Close plane of critical focus.Smaller moving-picture show format.Larger film format.Focus change integrity Selecting near and far distance which need to be held evenly and acceptably in focus and setting the focus distance to suit.Factors affecting Shallow depth of field effects in camerasHigh contrast lenses have less depth of field effects than the low contrast lens. Consequently, a keener diameter of center of confusion should be used in depth of field calculation.(eg- 1/2000 instead of 1/1000 )Lighting which sharply focused details, brilliantly lighted objects go out appear to have less depth of field effects.The use of lens filter in between the lens and the subject, which will reduces maximum definition and make a greater degree of soft focus.As usual but very common, depth of field effects situation arises with uses of wide-eyed incline lens at moderate focus distance.( for e.g. 3ft to 12 ft)Object at infinity This is occur especially when photographed utilize long focal length lens( more than 55 mm lenses) trend to appear tend to appear soft because of atmospheric elements( equal moisture, smoke, dust, haze, smog). There is solution too for such situation that is unaccompanied either use HAZE filters procurable in market or using light yellow filters to increase contrast and sharpness in film. This affects when you record or photographing in any hilly area, mountain area, beaches, waterfall, or any natural area sometime forest too).In case of shutter deplete Priority A fast shutter promote used in photography in order to capture fast sorrowful object( e.g. like if you regard to take a shot of moving car), whereas a wordy shutter speed used to create blur effects on fast moving object( for e.g. a fast moving car in night and you want to capture back light of car as beam using slow shutter speed) , so therefore a fast shutter speed requires a larger aperture size lets say (f1/16or f/11 ) which allow small amount of light to enter the lens hence it extended depth of field effects and in case of slow shutter speed requires small aperture lets say (f2.8, or f2) which allow more light to enter the camera and hence it produce shallow depth of field effects. When aperture is more open than it allows more light to enter the camera and fall on camera CCD, hence to control amount of light we need a more shutter speed to accumulate and to prevent the photograph from over exposed.A telephoto lens gives you a narrow depth of field effects, by moving a lens as close as to the subject and use largest aperture size of camera lens, while to get the large depth of field use Wide angle lens and move your camera and lens as far as possible and use small aperture size.The degree of magnification that the two-bagger may be subjected to when shown or projected close or near to the interview sheet to the disguise. I mean to say that when Audience close to a cinema screen will be more aware of soft focus than those who are far away from the cinema screen.Focus Bias This can occur when one subject is in focus and rest is in out of focus like in case of macro photography with small aperture and long focal length for eg a 200 mm lens with aperture value of 2. 8 or 2.0.Effects of aperture and the depth of fieldThe depth of field effects is being controlled by lens aperture value. If you increase the f-number than depth of field effects also increased but decrease the amount of light entering to the camera and when you decrease the f-number than depth of field effects also decreased (it gives shallow depth of field effect). In motion depression its very limited use of it. Generally cameraman take a single aperture settings for a shot and for another shot they choose another setting as par locality and they adjust pic settings with the help of light meter device which tells actuall amount of light presents in that area. Aperture settings and exposure settings are changed more frequently in s work cameras than motion picture cameras. In photography and cinematography, variation in depth of field effects used to create various kinds of special effects.Camera movement and the depth of field effectsIn film making, a person who looks and take s care of responsibility of lens changing, filter changing, point to focus, maintaining depth of field, setting focal length is cognize as focus-puller. Focus-puller is one of the assistant person in show offing crew members or camera man. A good focus-puller has very adequate and vast knowledge of cinematography. He has to focus and shift focus smoothly in such a manner that audience cant find jerk on them. In film industry most hard job is of focus puller. He has to perform his duty very accurately because suppose if any role disposed(p) to actor to act on that, and he done that, but while recording focus puller didnt check focal length and filter than actor has to act again. Doing reshot is tough to achieve same expression what he achieved in previous shot. So this was example how much focus puller important to the cinematography. His act is more technical rather than creative. He has to keep in mind all the guidelines given by the theatre director of photography during shoo ting a shot.Cameras depth of field limitsThe sharpness of depth of field can be increased by decreasing by Center of confusion, but its not as aristocratical to decrease because it also has some disadvantage that is motion blur and diffraction. As we know center of confusion has inversely relation with f-number like a smaller center of confusion need a greater f number, but need a long exposure time. if we increase f-number than diffraction also increases which will let on or soft all the part of image, thus image will no longer be in sharp.The f-number which will overcome from center of confusion is the minimum acceptable sharpness value. If we increase f- number than the sharpness at limited depth of field improved. As we know there is also maximum f-numbers through which sharpness of depth of field in image gets over. The best f-number should be chosen in between of minimum and maximum f-numbers.Depth of field and Macro or close-upOne of the main difficulties with close-up phot ography is that keeping the image enough in focus. The closer the lens focuses, the less depth of field you have. When using a macro lens at its maximum magnification, depth of field may only extend a fraction of an butt. With floral close-ups, a small aperture is almost always needed, but even so, it is important that the lens focuses on a key focal point in the composition, since not in the replete(p) frame.Depth of field and shooting on bright hot afternoonWhile shooting at outdoor especially in day light, the director of photography may wish to reduce amount of light and the depth of field for a close-up shot. For reducing light, a very good filter available called neutral density filter commonly known as ND filter. Suppose the light meter indicating F/22 but we have till f/16, than ND filter play a very important role. This will reduce the amount of light entering to the camera and enable you to shoot on bright sunny day. On other case, if the director of photography wants a close-up shot, and you have to reduce your depth of field, because by reducing depth of field, it will out of focused the background and puts more importance to the subject or highlight the subject.Circle of confusionWhile shooting the film, the focus puller essential be know that which part of scene should be sharp, so therefore we need something to measure the sharpness of image in relative to film limits of the eyes resolution at the time of viewing or at time of projection on screen.For example if a image is captured through 35 mm film projected at theater, audience must be at distance of 1/3 back from screen. Now we know that eye declaration power is 1 minute of arc. From audience I mean 1/3 back from screen, the smallest size of a dot appearing on a screen which is in perfectly focused or sharp. Now we can easily measures the distance between audience and the screen through any inch tape, from screen the previous sharpen dot which appeared smallest at back now that will be l argest dot from the screen, the arc of 1 minute comes up with somatogenic dimension on the screen for the largest dot that the audience previously seen as a smaller sharp point. construe 1 (need to put a plot over here)Now the diameter of dot on screen is not actual size of dot, to find actual size of dot we have to maneuver diameter of big dot appearing on screen, than we have to divide with enlargement factor needs to bring the size of our 33 mm film up to size of our cinema screen or projected area. This will bring the size of maximum or big dot.When lens is focused at infinityIf any point is focused from the infinity, the distance between plane of focus and the lens become the focal length of the lens.How image size varies at different points behind the camera lensFigure 2 (need to put a diagram over here)You can see the image is not at extract plane of focus. The image was there somewhere after plane of focus. So in this case size the dot size forming big. Now view if the a udience sees this dot size sharpen, clearly in focus, than we can easily calculate the amount of sharpness in which part of overall image looks sharp. around and far points of focusFigure 3 (need to put a diagram over here)In this case point B creating a sharp image on image plane or plane of focus, while point A creating image after crossing image plane or plane of focus, which means out of focus or blur or less sharpen image.ConclusionIn film plane, both near object and far away object (Lets take Point A and Point B) expanded and become confused to larger dot than the original dot. Hence this is the circle of confusion.Figure 4 (need to put a diagram over here)Thus, a center of confusion (COC) is the diameter of largest dot which is still considers being sharp, focused, and also seen by the audience in Film Theater when it projected on screen.Focus SplitFocus split is selecting the near and far distance which need to be held equally and acceptably in-focus and setting the focus di stance to suit.Lets take x as the distance of near object from the camera lensLets take y as the distance of far away object from the camera lensThan what could be the focus area?Hyper focal DistanceHyper focal distance is maximum depth of field that starts from infinity to the camera. If a lens is set to hyper focal distance, than the depth of field effects is half of hyper focal distance from infinity. Hyper focal distance is the distance in which lens is focused at infinity, so that the object in background and foreground both will be at sharper focused.Hyper focal distance depends on many factors, some of likeFocal length of the camera lensThe aperture f- valueDiameter of circle of confusionHyper Focal distance = (FL2)f X COCWhere FL means focal length, f-number means aperture size and COC means circle of confusionAfter knowing hyper focal distance, its easy to calculate near and far pointNear point depth of field = H X SH+(S-F)Far point depth of field = H X SH-(S-F)Where H = Hy per focal distance valueS = Distance from camera to the subjectF = Focal length of camera lensCOC = Circle of confusionFocus Bias Focus bias occurs when one object is in focus and rest is in out of focus (for e.g like in case of macro photography, with larger aperture and longh focal length, i.e f 2.8 with 200 mm focal length)In cinematography, focus plane yet depth of field effects is calculated using the entrance puple position of