SHUTTER SPEED & F-STOPS

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SHUTTER SPEED & F-STOPS. When you take a photo, the camera must let in just the correct amount of light to expose the film. - PowerPoint PPT Presentation

Text of SHUTTER SPEED & F-STOPS

  • SHUTTER SPEED & F-STOPS

  • When you take a photo, the camera must let in just the correct amount of light to expose the film.

  • A LIGHT METER in your camera reads the amount of light in the scene toward which you are aiming the camera, and decides how much light needs to enter the camera to expose the film just right.

  • Too much light hitting the film makes the negative overexposed. It will be very thick and dark, and hard to print.

  • Too little light hitting the film makes the negative underexposed and it will be very thin and hard to see. The prints will be difficult to print also.

  • So, whether your camera is automatic or not, a light meter will read the scene, decide how much light is needed for your film speed and..

  • either tell you by a meter reading in your camera ( a needle that moves up and down, or a red/green light, or a plus/minus sign) , or adjust itself automatically, for just the right amount of light to get a perfect negative.

  • ONE TYPE OF VIEWFINDER WITH METER READINGS ON RIGHT SIDE

  • You can learn how to control the amount of light yourself, so you can do creative things with your camera!

  • THERE ARE TWO WAYS TO CONTROL THE AMOUNT OF LIGHT THAT ENTERS A CAMERA

  • ONE WAY IS BY CONTROLLING THE LENS APERTURETHE SECOND WAY IS BY CONTROLLING THE SHUTTER SPEED

  • CONTROLLER NUMBER 1: THE APERTURE OR F/STOPS

  • the LENS APERTURE ALLOWS LIGHT TO PASS THROUGH A LENS CARRYING THE IMAGE TO THE FILM IN THE CAMERA

  • AN IRIS DIAPHRAGM IS USED TO REGULATE THE APERTURE OPENINGSIT IS LOCATED WITHIN THE LENS. If you remove a lens on an SLR camera, you remove the aperture with it!

  • AN IRIS TYPE DIAPHRAGM IS MADE OF DELICATE FLAPS THAT OVERLAP EACH OTHER

  • NUMBERS CALLED F- STOPS ARE USED TO MEASURE THE SIZE OF THE APERTURE OPENINGS

  • THE F-STOP NUMBERS ON YOUR CAMERA LENS

  • LOOKING THROUGH THE DIAPHRAGM AT DIFFERENT F/STOPS

  • THE APERTURE, OR F/STOPS, CONTROLS THE AMOUNT OF LIGHT GOING INTO THE CAMERA LIKE A FAUCET OPENING

  • THE WIDER THE APERTURE OPENING, THE MORE LIGHT WILL BE LET INTO THE CAMERA

  • THE F-STOP SYSTEM HAS BEEN DESIGNED SO EITHER TWICE AS MUCH LIGHT, OR HALF AS MUCH LIGHT PASSES THROUGH THE APERTURE AT EACH ADJACENT F-STOP.IMPORTANT:

  • FOR INSTANCE, F/2.8 LETS IN TWICE AS MUCH LIGHT AS F/4AND F/4 LETS IN HALF AS MUCH LIGHT AS F/2.8

  • CONTROLLER NUMBER 2:THE SHUTTER

  • A CAMERA SHUTTER IS LIKE A DOOR THAT OPENS AND CLOSES EITHER FAST OR SLOWLY

  • THE SPEED AT WHICH THE SHUTTER OPENS AND CLOSES CONTROLS HOW MUCH LIGHT ENTERS THE CAMERA ALSO. THERE ARE SEVERAL TYPES OF SHUTTERS

  • A LEAF SHUTTER IS MADE OF THIN BLADES THAT FIT TOGETHER TO MAKE A ROUND OPENINGYOU FIND THEM ON VIEWFINDER CAMERAS MORE OFTEN AS THEY ARE LESS COSTLY TO MAKE

  • CLOSEDOPENPARTLY OPENPARTLYCLOSEDCLOSEDA LEAF SHUTTER HAS PRECISION THIN METAL OR PLASTIC BLADES THAT OPEN AND CLOSE RAPIDLY

  • A FOCAL PLANE SHUTTER IS USED MOST IN 35MM SLR CAMERASTHEY ARE MADE OF FABRIC OR METAL CURTAINS MOUNTED VERY CLOSE TO THE FILM PLANE

  • THE CURTAINS MOVE ACROSS THE FILM FRAME, ONE AHEAD OF THE OTHER. WHEN THE SHUTTER RELEASE IS SQUEEZED, THE LEAD CURTAIN TRAVELS ACROSS THE FILM, FOLLOWED SHORTLY BY THE TRAILING CURTAIN. THIS ALLOWS LIGHT TO HIT THE FILM

  • THE SHUTTER SPEED DETERMINES HOW FAST THE CURTAINS MOVE IN RELATION TO EACH OTHER. THE FASTER THEY MOVE, THE LESS TIME THE FILM IS EXPOSED, AND SO THE LESS LIGHT REACHES THE FILM.

  • SLOW SHUTTER SPEEDFAST SHUTTER SPEED

  • SHUTTER SPEEDS ARE MEASURED IN FRACTIONS OF A SECONDONE SECOND IS VERY SLOW...WHERE 1/2000TH OF A SECOND IS VERY FAST.

  • SHUTTER SPEEDS ARE MARKED ON OR IN THE CAMERA ONLY BY THE DENOMINATION OF THE FRACTIONA SHUTTER SPEED SETTING OF 250 REALLY MEANS THE SHUTTER OPENS AND CLOSES IN 1/250TH OF A SECOND.

  • THE SHUTTER SPEEDS ARE USUALLY SET BY A DIAL ON TOP OF THE CAMERA

  • THE SHUTTER SPEED DIAL ON TOP OF A CAMERA LOOKS LIKE THISSOME CAMERAS JUST HAVE AN LED DISPLAY FOR THE SHUTTER SPEED

  • THE SHUTTER SPEED WITH A DIFFERENT COLOR IS THE ONE YOU USE WITH A SEPARATE FLASH ATTACHMENT!!

  • SHUTTER SPEEDS

  • SHUTTER SPEEDS

  • JUST LIKE F-STOPS, ADJACENT SHUTTER SPEEDS EITHER HALVE OR DOUBLE THE AMOUNT OF LIGHT ALLOWED TO ENTER THE CAMERA

  • SO, a 1/125 SHUTTER SPEED PERMITS HALF THE AMOUNT OF LIGHT AS 1/60AND 1/60 LETS IN TWICE THE AMOUNT OF LIGHT AS 1/125 OF A SECOND

  • SO YOU SEE, YOU CAN CHANGE THE AMOUNT OF LIGHT THAT ENTERS THE CAMERA IN TWO WAYS: BY CHANGING THE F-STOP AND BY CHANGING THE SHUTTER SPEED

  • USING EITHER WAY, YOU CAN EITHER DOUBLE OR HALVE THE AMOUNT OF LIGHT THAT ENTERS FROM THE PREVIOUS SETTING.

  • SHUTTER SPEEDS AND F-STOPS HAVE A DIRECT RELATIONSHIP IN REGULATING LIGHT

  • YOU CAN HAVE MANY DIFFERENT COMBINATIONS OF SHUTTER SPEEDS AND F-STOPS THAT ALL LET IN THE SAME AMOUNT OF LIGHT!!!

  • F-STOPSSHUTTER SPEEDSTHESE COMBINATIONS LET IN THE SAME AMOUNT OF LIGHT

  • THE COMBINATION OF THE F/STOP AND THE SHUTTER SPEED YOU USE TO TAKE A PICTURE IS CALLED THE EXPOSURE FOR THAT PHOTO.

  • SO, YOU MIGHT SAY, MY EXPOSURE FOR THAT TRAIN PHOTO WAS F/4 AT 1/500 SEC.

  • WHATS THE POINT!????

  • BY CHOOSING CERTAIN SHUTTER SPEEDS YOU CONTROL HOW MOVING OBJECTS APPEAR IN YOUR PHOTO (FREEZING MOTION, BLURRING MOTION, ETC.)1/1000 sec1/15 sec

  • BY CHOOSING CERTAIN F/STOPS, YOU CONTROL THE DEPTH OF FIELD IN YOUR PHOTO, OR HOW MUCH OF THE SCENE APPEARS IN FOCUS (LOTS OF DEPTH OF FIELD, NARROW DEPTH OF FIELD)f/16f/2

  • IF YOUR METER TELLS YOU AN EXPOSURE IS CORRECT FOR A SCENE, YOU CAN CHANGE THE RESULTS WITHOUT CHANGING THE AMOUNT OF LIGHT ENTERING YOUR CAMERA.

  • IF YOU CHANGE TO A SLOWER SHUTTER SPEED, JUST CHANGE TO A SMALLER APERTURE TO COMPENSATE. SAME AMOUNT OF LIGHT.DIFFERENT EFFECT!!! GET IT?

  • AUTOMATIC CAMERAS WITH MANUAL OVERRIDE CONTROLSWHAT YOU CAN DO

  • SOME CAMERAS ALLOW YOU TO CONTROL ONE OR THE OTHER AND IT AUTOMATICALLY CHOOSES THE COMPANION SETTING FOR THE CORRECT EXPOSURE.

  • IF YOUR CAMERA HAS THE SETTING:P = PROGRAMMED EXPOSURE, THEN THE CAMERA DECIDES AUTOMATICALLY WHICH F/STOP AND SHUTTER SPEED TO USE. YOU HAVE NO CONTROL, BUT THE FILM WILL BE EXPOSED CORRECTLY.

  • IF YOUR CAMERA HAS THE SETTING:A = APERTURE PRIORITY. YOU CHOOSE AN APERTURE OR F/STOP, THE CAMERA READS THE SCENE AND AUTOMATICALLY SETS THE CORRECT SHUTTER SPEED FOR THE FILM.

  • YOU CAN CONTROL DEPTH OF FIELD (HOW MUCH LOOKS IN FOCUS) WHILE STILL DEPENDING ON THE CAMERA FOR CORRECT EXPOSURE. IN FOCUSBLURRYBLURRYDEPTH OF FIELDMOO

  • IF YOUR CAMERA HAS THE SETTING:S = SHUTTER SPEED PRIORITY. YOU CHOOSE THE SHUTTER SPEED, THE LIGHT METER READS THE SCENE AND AUTOMATICALLY SETS THE CORRECT F/STOP FOR THE FILM.

  • YOU CAN CONTROL MOTION BLUR OR MOTION FREEZING, WHILE STILL DEPENDING ON THE CAMERA FOR AUTO EXPOSURE.

    HMM, SLOW SHUTTER OR FAST SHUTTER??

  • IF YOUR CAMERA HAS THE SETTING:M = MANUAL SETTING. YOU CHOOSE BOTH F/STOP NUMBER AND SHUTTER SPEED.

  • THE LIGHT METER READS THE SCENE AND TELLS YOU IF YOUR SETTINGS ARE TOO LITTLE, TOO MUCH, OR JUST THE RIGHT AMOUNT OF LIGHT FOR THE FILM. TOTAL CONTROL, BUT MORE ERRORS POSSIBLE.

    TOO MUCH LIGHT HITS THE FILMNOT ENOUGH LIGHT HITS THE FILMCORRECT EXPOSUREDARK NEGATIVELIGHT NEGATIVEJUST RIGHT

  • FILM SPEED IS THE SAME, F/STOP IS THE SAMEBUTSHUTTER SPEED IS 1/125 SECSHUTTER SPEED IS 1/60SECSHUTTER SPEED IS 1/30 SEC

  • FILM SPEED IS THE SAME, SHUTTER SPEED IS THE SAMEBUT APERTURE IS F/4APERTURE IS F/8APERTURE IS F/5.6

  • F/STOP IS THE SAME, SHUTTER SPEED IS THE SAMEBUTISO 400ISO 1600ISO 800

  • VERY WIDE DEPTH OF FIELD FROM A VERY SMALL APERTURE, SUCH AS F/22 OR F/16