GSFC Photography Club Beginners Class Session 2 – Camera Mechanics

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Scott Hull 12/3/2013. GSFC Photography Club Beginners Class Session 2 – Camera Mechanics. Agenda. Terms Camera Types Camera Parts Camera Settings Shooting Modes and Scene Modes Lenses Filters Flash Gadgets. Terms. ISO (ISO = ASA) (adjustable ) - PowerPoint PPT Presentation

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GSFC Photography ClubBeginners ClassSession 2 Camera MechanicsScott Hull12/3/2013AgendaTermsCamera TypesCamera PartsCamera SettingsShooting Modes and Scene ModesLensesFiltersFlashGadgetsTermsISO (ISO = ASA) (adjustable)The sensitivity of the CCD sensor chipAperture (adjustable)The amount of the lens diameter that you useWhite Balance (adjustable)The color correction for the light you are collectingOptical vs. Digital ZoomOptical zoom is where the lens moves to expand or contract the imageDigital zoom is a marketing tool basically just croppingLive ViewThe ability to view the image on the display while you compose the shotStopsA whole stop is a change in the amount of light by half or double1/250 sec 1/125 sec 1/60 sec400 ISO 200 ISO 100 ISO f/4 f/2.8 f/2Aperture numbers change by a factor of 1.4Square root of 2, since double the light is 2x areaArea of a circle is r2 : 2=1.414 is the change in diameterMost cameras now also use partial stopsCamera Types

Pocket CameraPoint and Shoot CompactDSLRDigital SingleLens ReflexDifferences Between Camera Types(in a very general sense)Pocket Cameras + phonesPoint and ShootsDSLRsSmall shirt pocketMedium purse Large carry or camera bagSnapshotsGood snapshotsDocumentation to artistryVery weak flash (~10)Stronger flash (~20)Internal (~20) + externalView the monitor onlyElectronic viewfinderLook through the lensShort range zoomShort to very long zoomInterchangeable lensesVery small sensor chipSmall sensor chipMedium to 35mm frameAuto focus onlyManual focus, but difficultEasy manual or autofocusVery lightweightNoticeable weightNoticeable to heavy weightImages OK for 5x7 printsImages OK for 8x10 printsImages OK for BIG printsVery inexpensiveReasonably pricedCan get very expensiveOften keep it with youGrab and goRequires preparationCamera PartsAll digital cameras have:LensShutterShutter releaseSensorComputerDisplay screenBattery

Most also have:ViewfinderBuilt-in flash - 20 tripod mountSome Have:Hot shoeMirror / prismBeam splitterGripSelection dial(s)Sensors(size does matter)

Blue box is 35 mm film frameThe difference (white area) is the crop factorCrop FactorReported relative to 35 mm filmSame focal length lens that was used on film camera now focuses onto a smaller sensorThe sensor image area becomes expanded when viewing, so it is effectively magnifiedBecause of this, a 100 mm lens on a Canon APS-C camera gives the same magnification image as a 160 mm lens would on 35 mm filmCamera SettingsShooting ModesScene ModesFocus ModesMetering/ Exposure CompensationFile Type/ Image QualityWhite BalancePlaybackA whole book full of others read that book! (the Users Manual)Shooting ModesAutoCamera selects everything: aperture, shutter speed, focus, flash - all of it, with no overridesUsually works, often doesntProgramCamera picks aperture & shutter speed; focus can be overriddenAperture PriorityUser picks the aperture, camera picks the shutter speed to matchOften the preferred go-to mode for experienced photographersShutter PriorityUser picks the shutter speed, camera picks the aperture to matchManualUser gets to/ has to pick all settings

Scene ModesPortraitLandscapeNight SceneNight PortraitSportsIndoorMacroSelf PortraitSunsetFireworksFood DocumentsBeach/SnowUnderwater (4 options)SnowClose-upMuseumBacklightPanoramaCandleProbably many moreA Few Common Scene ModesSportsIncreases ISO, for faster shutter speedLandscapeChooses narrower aperture, for longer depth of fieldPortraitChooses wider aperture, for short depth of fieldNight PortraitLong exposure for background, plus flash for facesFireworksVERY long exposure (seconds) should use a tripodBeach/SnowCompensates for bright reflections by increasing exposureNight SceneIncreases ISO, for greater light collection, no flashFocus ModesAutofocus on most new cameras is pretty darned goodEven experienced pros are starting to use it instead of always manually focusingStill not always perfectly crispDoesnt work for all situationsVery dependent on high contrast areasFocus point can usually be defined on DSLRsMight still need to tweak the sweet spotManual focus on pocket cameras and point and shoots is difficult, if possibleMeteringAverageOriginal film approach, not used much anymoreMulti-zone metering (aka Matrix, ESP, other names)Most commonly used default modeMysterious algorithms consider many factors including focus point, light distribution, etc.Center-weighted averageCentral portion represents most of the inputSpot~1-5% of the fieldLocation is usually definable, often in the centerUse exposure compensation (+/-) to make small adjustmentsFiles/ Image QualityRAW vs. JPEGRAW is all of the data, straight from the sensorLargest files, most flexibility later, and highest resolutionJPEG is processed and compressed before savingLosses occur each time it is savedUsually several levels of compression availableWhy not just maximize everything with RAW?E-5 Example (12.3 MP camera)RAW file: 12.4 MB, High quality JPEG: 5.3 MBLittle discernible loss in image quality until you zoom inIn fact, RAW initially looks much noisier at high magnificationMemory cards are big, but not infinite capacityRAW is also not as portable between viewersWhite BalanceColors change based on the type of lightLight brown shirt in incandescent light can look green in fluorescent lightEven sunlight vs. shade makes a differenceImage is interpreted differently based on settingsAuto white balance is pretty good ~98% of the timeCheck your display frequently, and change the WB if necessaryRAW images are not corrected, so you can change it later if it was incorrectMost DSLRs can also set WB manually for unusual situationsLensesBuilt-in vs. interchangeableDepends on the camera typeFixed vs. zoomFixed is typically lighter and has higher image qualityZoom is more flexibleCheap vs. expensiveMore expensive lenses have more elements, better coatings, wider apertures, heavier weightMacro capabilityHighly detailed close-up imagesTeleconvertersGoes between camera and lens to produce 1.4, 1.6, or even 2.0 x the focal lengthZoom Lens CautionsA wobble of only 0.03 will cause the image to move by 1/8 at 20 feetWith a 50 mm lens, you may not see thatWith a 400 mm lens, it is 8 times bigger, and very noticeableZoom lenses are also usually unbalanced when hand heldMore likely to get that 0.03 - or moreThey also tend to have smaller maximum apertures, so longer exposure timesTripods help, but faster shutter speeds are more practicalTripod pointing is awkward and slowFaster shutter usually means higher ISO, though more noiseThus, the driver for more expensive, faster zoom lensesImage StabilizationUses tiny gyroscopes to detect movementOptical Image StabilizationLens shifts the optical path, to stabilize the imageUnique to the lens; extra $ for each lensCanon, Nikon, some Sony, PanasonicSensor shiftSensor is moved to stabilize imageWorks with all lenses, even old film lensesOlympus, Pentax, some Sony, Konica-MinoltaDigital Image StabilizationUsed in some video camerasComputer changes the pixel region from frame to framePerformance is rated in equivalent stops improvementTurn image stabilization OFF when using a tripodFiltersUltravioletMostly to protect the lensCheap, and nearly invisible in the imagePolarizerReduces glareRotate for best effectivenessInfraredSees heat, for an other-worldly effectNeutral DensityReduces light, without shifting colorsColorHighlights individual colorsGradientNeutral density on one end to clear on the otherGreat for darkening skiesFlashObviously used to brighten a sceneFlash power is determined by the Guide NumberGN = distance x aperture, at a specific ISOExample: 18m at ISO 200 (Olympus E-5 internal)Means that at f/5.6 and 200 ISO, anything beyond 3.2 m (~11 ft) will not be fully illuminatedExternal flash GN is typically about 30 to 50Can be moved off-axis, to control shadowsMany are remote triggered; can use multiple units

GadgetsTripodShutter releaseRemote controlMonopodCamera BagLens capsSpare batteriesSpare memory cardsReflectors/ diffusersGPS data taggerThe list goes on and onWhat next?Now that I figured out my camera and Im taking great pictures, I have a bunch of pretty files. What can I do with them?Photoshop ElementsIf you think they look great now, just waitElements has the same basic tools at ~1/10 the pricePrintsCostco, Target, Wal-Mart, etc.Probably not worth getting your own printerUsually clog up if you dont print a lot of picturesCreate a photo book about a subject (cheaper than you think)Online software and Elements both make it pretty easyPost them onlineRecommend a Flickr free accountPhoto Club Flickr site we want to see what youve done!Facebook, other social mediaBackup SlidesExposure ReviewSunny 16 RuleOn a sunny day, at f/16, the shutter speed is 1/ISOStop ActionTripod Zone Exposure ReviewSunny 16 RuleOn a sunny day, at f/16, the shutter speed is 1/ISOThese ISOs are one stop apart.Stop ActionTripod Zone Exposure ReviewSunny 16 Rule in the shade (-2 stops)At f/16, the shutter speed is 1/ISO + 2 stops1/100 sec + 2 stops more light is 1/25 secStop ActionTripod Zone Exposure ReviewSunny 16 Rule indoors (-4 stops)At f/16, the shutter speed is 1/ISO + 4 stops1/100 sec + 4 stops more light is 1/6 secStop ActionTripod Zone Pixel Size determines light gathering abilityCameraPixels (MP)Sensor Size (mm)Sensor Size (pixels)Pixel Size (m)Crop FactorNikon D406.023.7 x 15.53008 x 20007.91.5XNikon D20010.0 23.6 x 15.83872 x 25926.11.5XNikon D9012.323.6 x 15.84288 x 28485.51.5XCanon 450D12.2 22.2 x 14.84272 x 28485.21.6XCanon Rebel T2i18.0 22.3 x 14.95184 x 34564.31.6XCanon 60D18.022.3 x 14.95184 x 34564.31.6XOlympus E-512.317.3 x 13.04032 x 30244.32XCanon A955.07.14 x 5.362592 x 19442.8-----Canon PowerShot SX150 IS14.16.17 x 4.554320 x 32401.4-----

Smaller pixels mean less li