20-03-2012

Workshop One - Location       20-03-12

Belinda Pratten                          Week Six                            Semester One

·         Blogs – you need LOTS of pictures

·         Look for the centred template

·         Check that all links work

·         The ideal shutter should 

·         expose each part of the film/sensor equally and simultaneously

·         be silent in operation

·         be vibration free

·         little effort to set in motion

·         effective exposure should be repeatable

·         …it does not exist

·         Faster speeds require the second curtain to closely follow the first creating an increasingly narrower ‘slit’ traveling across the sensor.

·         Focal Plane (FP) shutter - limitations

·         flash should only operate when shutter is fully open

·         ‘flash’ synchronization is therefore limited 

Information is recorded bottom to top

·         Between The Lens (BTL) or Leaf shutter

·         operates between lens elements

·         must be ‘cocked’ during lens attachment/removal

·         max speed of 500th sec

·         synchronises with electronic flash at ALL speeds

·         most medium format cameras

·         perfect shutter open instantly, closes instantly

·         efficiency is affected at high speeds

·         at 500th a greater proportion of the time is used to open and close the shutter so exposure is actually less than expected

·         often 400th is used, inefficiency reduces exposure closer to that of ideal 500th sec

·         shutter opens and closes at the same rate regardless of shutter speed chosen

·         shorter time to uncover a small aperture

·         longer time to uncover a large aperture

·         Panning is a continuous semi circle movement

·         The Diaphragm

·          In optics, a diaphragm is a thin opaque structure with an opening (aperture) at its centre.

·          The role of the diaphragm is to stop the passage of light, except for the light passing through the aperture.

·        

Intensity y

Time 250

DOF definition

·         The region of acceptably sharp focus around a subject
position, extending toward the camera and away from it,
from the plane of sharpest focus. 

The boundaries of depth-of-field are referred to as the
near limit (d1) and the far limit (d2).

                                                        Davis - Photography, 5th Ed.

·         Depth of field is increased by:

·           using smaller apertures

·           using larger subject distances

·           using wider angle lenses

·         Large aperture- smaller DOF

·         Small aperture – larger DOF

·         Lens focal length 70mm longer less DOF

·         Lens focal length 20mm wider more DOF

·         Copy work you should use around f.11

·         Architectural work around f.32

·         Automatic diaphragm

·         stays fully open until shutter release is pressed, then…

·           diaphragm closes down to preset aperture.

·           shutter opens and closes.

·           diaphragm opens up fully again.

·           why?

·           too dark if stopped down during focusing

·         Depth of field preview

·         If diaphragm is at max-aperture during viewing then
extent of depth of field cannot be seen.

·         All cameras have a depth of field preview function.

·         Actuate this and the diaphragm stops down to the preset
aperture so that you can see the depth of field present
for that aperture.

·         Automatic Diaphragm

·         Maximum aperture until shutter is released

·           Diaphragm closes down to chosen aperture.

·           Shutter opens then closes.

·           Diaphragm opens to maximum again.

·           Why is this function necessary?

·           At small apertures not enough
light passed for the eye to view/focus

·         Blog – Hyper focal distance

·         Visit Elearn to find 10 questions

·         Digital Capture

·         Sensor array type

·         CCD (charge-coupled device)

·           CMOS (complementary metal oxide semiconductor

·          Sensor Array’s – pixels

·         millions of sensors (photosites)

·           each sensor = one pixel (picture element)

·           Nikon D200 10.2 million pixels

·         From highest number to lowest

·           total pixels:                               total on sensor including inactive ones

·           effective pixels:      active pixels and any ignored pixels
                                        used eg. to establish blacks

·           active pixels:                            effective pixels less ignored pixels

·           recording pixels:     the pixels in your image.

·         Nikon D200

·           total pixels:                               10.92 million pixels

·           effective pixels:      10.2 million pixels

·           active pixels:                            no data

·           recording pixels:     10.04 million pixels

·           each sensor/photosite records a level of light but NOT its colour

·           known as a RAW greyscale capture

Intensity y

 

                                                                                                                                                   

·         Where does the colour come from?

·         RGB filter array above sensors (Bayer pattern- Bruce E Bayer, Kodak, 1976)

·        
RED filter:                                                                                                                passes only red light

·         GREEN filter:                                                                                                          passes only green light  (extra green sensors = human vision)

·         BLUE filter:                                                                                                              passes only blue light

·         RGB of subject is recorded as 3 separate parcels of data

·         camera ‘decoder ring’ stores data as a number representing each colour

·         Interpolation?

·         camera RAW CONVERTER interpolates data to build greater number of pixels in final image (known as de-mosaicing)

·           the three packets of data representing the RGB components are  compiled to form a full colour image.

·         RAW file capture

·         camera captures a RAW GREYSCALE image

·           ‘decoder ring’ records colour information.

·           RAW converter interpolates ‘missing’ pixels

·           RAW converter creates a RAW RGB file

·           so what’s the big deal about a RAW file?

·           all cameras capture RAW greyscale and convert to RGB

·           simple cameras automatically produce JPEG

·           pro camera gives options, RAW and/or JPEG

·         JPEG

·           calculates minimum data for adequate image

·           dumps unnecessary data

·           manipulation of file is limited

·           saving = data compression = further data lost

·           reopening = interpolates to re-establish file

·         RAW

·           all data is retained

·           infinite adjustments possible - no loss of data

·           adjustments in RAW are not permanent

·           save copies in other formats

·           original RAW retained

·         general term for a range of proprietary file formats, eg.

Canon:                                                                                                                                  CRW and .CR2
Minolta:                                                                                                                               MRW
Olympus:                                                                                                                             ORF
Nikon:                                                                                                                                   NEF
                                                                                                                                   

·           each manufacturer has slightly different RAW converters but all
   produce similar files with similar possibilities.

·           your processing or editing/manipulation software must be able to
   read your camera’s RAW file format.

·           Digital Negative (DNG)
   universal raw format to future-proof your files.

·         What else does a raw converter do?

·         applies a pre-set white balance (stored in METADATA) not permanent

·           applies a colour value to each pixel - ideally based on human vision

·           applies adjustments so that tonal range distribution more closely
   corresponds to human vision.

·           applies pre-set noise reduction, shadow areas, particular high ISO

·           applies pre-set image sharpening - no camera sensor array is perfect

·           applies pre-set anti-aliasing to adjust edge effects in image

·           These can also be adjusted within the processing/editing software.

·         What is RAW processing

·         Making adjustments (yours or clients) and saving to a particular
   file format in known as processing.

·           eg. white balance, colour space, sharpening etc. and then saving
   preferred file format, TIFF, JPEG etc.

·           Processing software can be proprietary such as;

Canon Digital Photo Professional
Nikon Capture NX
Phase One’s Capture One
Hasselblad’s Phocus

·           or general such as;

·         Photoshop, Lightroom, Apple’s Aperture

·         Silver FX pro – black and white

·         Presethaven.com – free presets for lightroom

·         Presets – User presets

·         Don’t use the following on your images

·         Heavy vignetting

·         Colour cast

·         Over sharpening

·         Saturation

·         Documentary Photographers

·         Chronicle, significant and historical events

·         Truthful objective and usually candid photography

·         Social (comment on society)

·         Photojournalism

·         Street

·         Celebrity

·         Sally Mann

·         Henri Cartier Bresson

·         Robert Capa

·         Robert Frank

·         Kevin Carter

·         Robert Doisneau

·         Dorothea Lange

·         Subscribe to Magnum Photography

·         Harold Cazneau

·         Max Dupain – the sunbaker

·         David Moore

·         Diane Arbus

·         Modern documentary photographers

·         Assignment 1 inspiration handed out

·         Assignment 2 Proposal for folio handed out

·         Location folio Documentary handed out

·         Wild light

·         Occuli

·         Magnum