ACM202 Week 10 Lecture Notes

About Digital Images

These are not really new.  E.g. mosaics were tessellations of tiles (often square like today’s pixels)

  • 150 years ago there were people who were looking at this sort of thing

Digital imaging is one step in the journey of communication –

The signal – is broken down into discrete parts in a digital image – whereas in the analogue image – the continuity (e.g. light waves, photons, sound waves,) are retained.  E.g. the Bayer array in the camera’s sensor is discreet squares, but film takes a perfect image of what impinges on it, limited only by the acuity of the light sensitive chemicals.

With an 8 bit RGB jpeg – 256 levels, within each primary channel.  (See cloud for the explanation – the rgb numbers will describe close to 17 million colours.  The eye can detect even more.)

Digital information can be made into many ‘products’ – e.g. A print, a sound, a set of text

Charles Babbage (1791-1871)

Made a proposal for a difference engine – a machine of gears, cogs and moving parts – essentially a computer.  (nb. till recently, a computer was ‘one who computes’ – i.e. a mathematician who e.g. made predictions based on numbers – e.g. meteorology, actuarial calculations)

Photography – 1830s (invention announced 1839 – e.g. William Henry Fox Talbot (whose negative photography allowed multiple images compared with Daguerre’s single image)

Film clip – on Cloud – History of Imaging

Camera obscura (around 5th century or before) – e.g. Aristotle (viewing of solar eclipse), camera obscura (Da Vinci), addition of lenses to focus the beam.

How to create a permanent image from this concept?Nieppes (8 hour exposure) – he knew Daguerre – who saw it as a money making project – silver plate in a box with silver iodide, after exposure, expose the images to mercury vapour – which gives an oxidization (lighter areas) – producing a positive image – not reproducible (unlike Talbotype’s negative process) – Daguerre donated the process to the French government (who gave them a pension) who gave it to the world.

Talbot’s ‘photogenic drawing’ – creating a negative – also developed the Calotype (image on paper)  – not as sharp as the daguerreotype – (Daguerrotype is a mirror image,

Later photography experiment by Daguerre –

Later – development of collodium (binding agent) to attach the chemicals to the glass (but only worked while the medium was wet) – wet process (must be developed on site)

No enlargement available – hence larger format style cameras.  (the photographer therefore had a field lab – with all the glass plates,

Amberotype – a glass negative – bleach – put on black background.  (backwards, non-reproducible)

Tintype – an easier process – much cheaper – led to shop-front photographers.

Note: Some modern photographers still use some of these methods (e.g. Daguerreotypes) Also Morell – works with camera obscura (also James McArdle – DU)

Video – Calculating by Steam – about the creation of the computer

Background – the industrial revolution – need for huge amounts of data – need for ‘computers’ – need for accurate figures – led to Charles Babbage’s concept of a mechanical computer which would never make mistakes.  = The difference engine (1822) – part funded by British government – The precision of parts was not initially available – Babbage worked on making tooling machines to increase precision.  Babbage’s work was intricate and not well understood – finally in 1832 – a part of the machine was produced which produced absolutely correct calculations – but the government pulled its funds (Babbage, by this stage wanted to produce a new machine – the analytical engine _ to be a very similar in structure to modern day computers e.g.

  • Mill= processor
  • Store= memory
  • Punch card =data entry

‘World’s first programmer’ – a woman (Ada Lovelace) who understood Babbage’s work and documented it.

Babbage’s machines were actually mechanical computers.

100 years later a programmable computation device was again conceived.

(There is a second part to the video – moving into 20th Century)

Pertinence to our work – the information was on punch cards – reducing of information into ‘bits’ – actually a ‘digital’ process – a switch – on/off (0,1 in binary code)

1839 – the first ‘digital’ image – could be expressed as 1 & 0.  J.M Jacquard portrait encoded in punch cards ( A silk image in black and white)

The industrial revolution – textiles – carpet design – Joseph Marie Jacquard – a machine, when attached to a loom, made much more intricate designs available – slats with holes which were then – holes/not holes – a matrix of digital information (also Geelong Wool Museum loom)

(Early computers also used punch cards) –

Note – at the same time as photography was being developed, so also a digital style system of punch cards to produce (and reproduce) e.g. carpets, textiles

Willard Boyle & George Smith – Charged couple device (CCD) – led to later award of the Nobel prize for physics.

Babbage’s work also included contact prints of machine woven lace (made by Henry Fox Talbot) – another link between the invention of photography and digitization.  (a ‘photogram’ process)

Samuel Morse (1821)– dots and dashes – standardized code – and spaces between which allowed the telegraph to send the code over long distances – this could then be decoded at the other end.  (Developed by his concerns about the slowness of messages – following his failure to hear of the death of his wife before her funeral.)  Morse visited Daguerre soon after Daguerre invented the Daguerreotype – and took the process back to the USA where he disseminated it.

Note – many of these innovator/inventors – knew each other and of each other’s work.

Alexander Graeme Bell – experimented with the concept of transferring images down the telegraph line – (transmission of light and sound) –

Fax – sending binary information through wires which is then decoded into an image

See Cloud for more detail.

Developments in digital imaging – current

e.g. Hasselblad 200 mb camera – video on cloud – a multi-shot camera (can shoot 4 shot or 16 shots)

The movement of the camera actually gives the actual value of the real colour (by moving the sensor one pixel four times) similarly the 16 shot mode (moves the camera by ½ a pixel) – this actually quadruples the resolution of the camera- This gives a more refined resolution without sacrificing noise, bit-depth etc.  – exposures are actually in layers (huge files) – incredibly sharp and deep colour – no noise –

Leica – monochrome camera – DSLR – (e.g. Henri Cartier- Bresson used a Leica) – The Bayer array has no coloured filters over the pixel array – hence there is no loss of light on the sensor – the actual light impacts exactly upon the array –

The B&W Leica produces excellent images with low noise in very low light conditions.  (Sean suggests that there may at some time be a camera where the Bayer filters may move away to give superb B&W images)

Compare with e.g. phone cameras – Lytro Camera – infinite focus (after the event – touch screen)

Pentax Sei camera –

Instagram (Socialmatic) camera – social matic camera – 3D filters – can also produce a polaroid style hard copy.  (See links on Cloud presentation –

Memoto – a mini-portable-life-bloggable camera – set to a timer – takes 2 geo-tagged shots/minute.  – a ‘virtual diary of your photographic memory’ – cloud enabled – i.e. the information goes to the cloud –

Juxtaposing of real and virtual images to create a picture

Development of architects drawings into 3D images – e.g. of buildings – (a cad style photograph – a virtual image)

Replacement of printing with e.g. projections – e.g. the digital whiteboard – or image projection with interaction – using a pen or ring to interact with the image – could be used e.g. for theatre

This technology – can be used for activism – e.g. projection on a London building against the re-election of Boris Johnston – the projector was in a bike which was moved around London – so couple projected anywhere.

Augmented Reality

Google Glass

Virtual Reality contact lenses (e/g/ contact lenses which may enhance vision)

Bionic contact lenses.

New Internet Art developments

The Creators Project – Rafael Rozendaal

e.g. a gif of Duchamp’s bike wheel – Discusses the concept of ownership within the digital art framework – interactive works – e.g. paper –

‘finding the perfect form for my idea’ – first drawings, then the sound, e.g. the popcorn popping art work.

The BYOP project (bring your own projector) –

The internet art can be both public (and free) and then sold to a collector – the sale is actually the artists’ name – the collector is actually a patron for the art –

New business models for digital art.

The economy for art works is scarcity – but on the internet – there are a limitless number – so how is value derived?  One can sell a photograph – in e.g. an edition (but negative is still available).

What is the market for video art.

Bill Viola – video artist – Continuously looped works – (Viola employs models/actors – are slow motion – reflections, water) – Viola sells the rights to show his works within a gallery (e.g. more than $1 million for one work) –

The business model that may work in the future – may not be invented yet – e.g.

Research – WordPress – checked out how to open links in a new tab – using menu page.


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