Digital Basic Class 3

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Traditional Film Speed: 

Traditional Film Speed Traditional film has a grain structure The size of the grain dictates image characteristics

Digital images have pixels: 

Digital images have pixels

Image resolution: 

Image resolution The greater the number of pixels in the image the greater the resolution Finer image detail Sharper edges More is better

Image size can be reduced: 

Image size can be reduced Image size can always be reduced or cropped Increasing size necessitates interpolation by the software Least desirable

Grain Structure Dictates Image Characteristics: 

Grain Structure Dictates Image Characteristics

ISO : 

ISO Higher the ISO the more sensitive to light

Slow Speed Film 25 to 100 ISO: 

Slow Speed Film 25 to 100 ISO Fine grain structure Thin emulsion Large degree of enlargement Wide tonal range Little exposure latitude High inherent contrast Landscapes / documentation

‘Fast’ Film 400 and Higher ISO: 

‘Fast’ Film 400 and Higher ISO Large grain structure Photography under diminished light level ‘Grainier’ appearance Greatest exposure latitude Action photography, low light Photojournalism

Medium Speed 125 to 360 ISO: 

Medium Speed 125 to 360 ISO Intermediate characteristics General all round film Portraiture / architecture

Digital Speed: 

Digital Speed Vary ‘speed’ at the touch of a button to suit lighting conditions It’s not free - noise

Credo: 

Credo For the finest image - shoot at the lowest film speed setting possible under the circumstances Assume the characteristics as for film

Shoot at highest resolution: 

Shoot at highest resolution Hindsight is 20/20 Better to reduce than increase Demands more memory Lower resolution allows more images to be stored

Increasing size leads to Pixelization: 

Increasing size leads to Pixelization

By the same token: 

By the same token Always save full resolution image in colour Camera may have settings for black and white or sepia etc. but best to convert copy later in other software

File Formats: 

File Formats Jpeg .jpg, jpeg Tiff .tif, tiff Gif .gif Photoshop .psd Raw .crw

JPEG: 

JPEG Joint Photographic Expert Group Greatest degree of compression Lossy Browser friendly Sacrifices colour for tonality

JPEG settings: 

JPEG settings

JPEG levels: 

JPEG levels

JPEG levels: 

JPEG levels 12 6 1

Tagged image format .tif: 

Tagged image format .tif Lossless – no compression Greater memory demand LZW compression Not web friendly

Graphic Interchange Format .gif: 

Graphic Interchange Format .gif Graphics, cartoons, solid colours Available only to indexed colour Banding in smooth transitional areas

Gif: 

Gif Reduces image to the 256 colours available to the indexed palette for web

RAW: 

RAW All information captured prior to camera manipulation, for information available for colour balance Lossless 8 or 16 bit colour Larger file size

Photoshop .psd: 

Photoshop .psd Adobe Photoshop’s native format Lossless Saves layers and alpha channels Working file

Resolution for purpose: 

Resolution for purpose Web and e-mail 72 dpi Newsletter 150 dpi Print / Photo 300 dpi

BTW: 

BTW Lithium batteries will die between shots Never remove card while camera is writing Is it really necessary to have the date and time on the image?

Film Speed: 

Film Speed ISO Higher the ISO the greater the sensitivity to light 100, 200, 400, 800, 1600

Film speed: 

Film speed Lowest ISO under the circumstances Outdoors – 100 Indoors – 400 Not free - noise

Depth of Field: 

Depth of Field

Depth of Field: 

Depth of Field

Depth of Field: 

Depth of Field

Depth of Field: 

Depth of Field

Depth of Field: 

Depth of Field

Depth of Field: 

Depth of Field

Depth of Field: 

Depth of Field Shallow

Depth of Field: 

Depth of Field Deep

Depth of Field: 

Depth of Field f 2.8 f 22

Depth of Field - Subject distance: 

Depth of Field - Subject distance

Depth of Field - Focal length: 

Depth of Field - Focal length

Depth of field: 

Depth of field Subject separated from background ‘Selective focus’ Hence - aperture priority

Depth of Field: 

Depth of Field Picasso Photographic wannabe

Depth of Field - Shallow: 

Depth of Field - Shallow Wide aperture – lowest number eg. f 2 Go close Long focal length

Depth of field Shallow: 

Depth of field Shallow

Depth of Field - Deep: 

Depth of Field - Deep Small aperture – high number eg. f 22 Far Wide angle DEP

S’plains why …: 

S’plains why … 1.4 2 2.8 4 5.6 8 11 16 - f# I I I I I I I I 250 125 60 30 15 8 4 2 -speed Equal exposures

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