Photography Basic By Henry C. Ng, APSA, EPSA. Topics Basic Photography theory Image sharpness Basic camera functions Digital Photography Basic composition.

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  • Photography BasicByHenry C. Ng, APSA, EPSA

  • TopicsBasic Photography theoryImage sharpnessBasic camera functionsDigital PhotographyBasic composition

  • Basic photography theoryRight amount of lightISOShutter speedf-stop

  • ISO speedHow fast it can absorb lightISO 100ISO 1600Higher resolution/quality

    Absorb light fasterLower resolution/quality

    Absorb light faster

  • f-stopThe circular area that open from the lensf1.4 f2.8 f3.5 f4.0 f5.6 f8 f11 ::::: f22 f32Shorter depth of field

    Let more light in (can take picture in lower light) Longer depth of field

    Let less light in (need more light to take a picture)

    Fast LensSlow Lens

  • Depth of FieldThe distance from the front to the back of the focused subject that remaining sharp

    Depends on :f-stop and the lens focus length

  • Depth of field (f-Stop)The distance from the front to the back of the focused subject that remaining sharp.f1.4f11f22f5.6Depth of field distance

  • Depth of field (Lens Focus Length)Wide angle Lens12mm 20mmNormal Lens50mm 55mmTelephoto Lens135mm aboveLonger depth of fieldShorter depth of field

  • Depth of Field Distance50 mm/ 2.8Example 1: f2.8Example 2: f5.6D= 2.8 / 50 = 0.56 mm50 mm/ 5.6D= 5.6 / 50 = 0.112 mm

  • Image sharpnessDepth of field

    Lens sharpnessf1.4 f2.8 f4.0 f5.6 f8 f11 ::::: f22 f32LongerShorterSharperf1.4 f2.8 f4.0 f5.6 f8 f11 ::::: f22 f32Total Image Sharpness =f1.4 f2.8 f4.0 f5.6 f8 f11 ::::: f22 f32HiLowLess Sharp

  • Camera Basic functionsShooting modesAperture priority (Av)Shutter Speed priority (Tv)Program mode (P)Manual mode (M)Others SportPortraitSunny dayCloudy day, etc.

  • Picture-taking work flowSet ISO to the lowest (why highest image quality)Select the lens focus lengthSet Tv or AvUsing Av if camera is on a tripodthe biggest depth of field f-stop if want very sharpThe largest f-stop if want short depth of fieldUsing Tv mode if hand heldStop motion the fast enough shutter speed (just a little higher than the 1/ longest focus length of the lens used)Blurring using slow speed.Test if not enough light set the ISO higher

  • Exposure BracketingWhy ?Sometimes, the light meter may not be able to measure the light exactly in the scene. Therefore, to make sure that we can have a good exposure picture, we bracket the exposures.Can be done in f-stop or shutter speed.

  • Digital photographyWhat are the major differences ?Not much, instead of capturing the image light on film, it capture the light from the image and record it in digital numbers.The differences are so little, but using it is a lot different.

  • Digital photographyLens factoring35 mm film/ full frame CCDAPC CCD 35 mm filmDigital CCD effective focus length = focus length x factor

  • Digital image file formatJEPGTIF or TIFFRawEtc.

  • HistogramWhat it means: the number of pixels in the picture that has the same tone valueWhite (254, 254, 254)Black (0, 0, 0)

  • (histogram) What it means: the number of pixels in the picture that has the same tone valueWhite 254Black 02152152151351351351352153535215

  • (histogram) What it means: the number of pixels in the picture that has the same tone valueWhite 254Black 02152152151351351351352153535215

  • (histogram) What it means: the number of pixels in the picture that has the same tone valueWhite 254Black 0

  • (histogram) What it means: the number of pixels in the picture that has the same tone valueWhite (254, 254, 254)Black (0, 0, 0)Red ChannelGreen ChannelBlue ChannelCombine Channel

  • (histogram) By looking the histogram, we can find out whether the image information is fully captured.If there is clipping, that means some of the image information was not captured.

  • The use of histogram infoBy looking the histogram, we can find out whether the image information is fully captured.If there is clipping, that means some of the image information was not captured.

  • Basic Composition RuleRule of third

  • Basic Composition RuleRule of third

  • Basic Composition RuleRule of third

  • Basic Composition RuleRule of thirdLocations that most attracting human attention

  • Beautiful sceneNice subjects placementsBut still lacking somethingMany times we may not able to make that perfect composition

  • Fill the empty areaMuch tighter compositionand making the picture standout

  • Back lightedSubjects stood outNo empty space perfect composition

  • Image LightingFront light (image appears flat)Side light Back light

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