Good Picture 2007: The Imaging Chain

An RPS Symposium - Papers Presented

Following the success of the previous four Good Picture Symposia, the Imaging Science Group of the Royal Photographic Society held another in its series of tutorial seminars (on 18 December 2007) on selected technical aspects of Digital Imaging. The aim of these lectures and discussions is to provide imaging practitioners, keen amateurs and students with insights into Digital Imaging and provide some tools and guidelines for assessing cameras and output. Some of the papers presented may be downloaded (see links below) by kind permission of the authors, as and when the files become available to us.

Programme

Dr. Graeme Awcock - Phurther Phantastic Photosites
University of Brighton
The "Phantastic Photosites" presentation at "Good Picture - 2006" looked at the principles of CCD image sensors with their capabilities and limitations in the context of Digital SLR applications. This presentation will investigate some of the developments that are being offered by manufacturers that complicate the issue of answering the questions "how many pixels have I really got?" and "how many pixels do I really need?"

Dr. Hani Muammar - Lenses for Digital Cameras
Kodak European Research, Cambridge
The quality from DSCs has improved significantly in recent years. This has been partly due to the advances in sensor technology which has resulted in increases in image resolution. However these improvements would not have been possible without advances in the imaging optics. An overview of camera lenses will be given with emphasis being placed on application to digital cameras. The pros and cons of using current (legacy) lenses designed for 35mm film SLR cameras with digital SLR cameras will be discussed. Recent developments in lenses for small digital cameras will be reviewed.

Dr. Alan Hodgson - Astronomical Telescopes as Camera Lenses (1.4Mb PDF file)
Independent Consultant
Probably the best known set of camera optics in Earth orbit is the Hubble Space Telescope. However, there are many other satellites using smaller optics that instead of looking outward are involved in Earth surveillance activities. This presentation will look at some of the attributes of these and using these lessons will show the sort of results that you can achieve using a consumer astronomical telescope as a lens for a digital camera.

Dr. Tony Kaye and Dr. Harry Adam - Photography in the RAW (2.6Mb PDF file)
Imaging Consultants
Professional DSCs and those for advanced amateurs allow the capture of "RAW" images. This talk will address what "RAW" files are, and what advantages/disadvantages they offer compared to fully rendered JPEG or TIFF images created "in camera". Photographers regard a "RAW" image file as a digital negative that must be "developed" using a "RAW" converter. In the same way that no two film developers are the same, we will show that "RAW" converters differ in characteristics, and will compare and contrast the results obtained with different "RAW" converters with fully rendered in-camera images.

Richard Sharman - Image Optimisation (2.7Mb PDF file)
Imaging Consultant
You may have a camera with multiple exposure modes, your workflow may be fully colour managed, but still some images may be disappointing. In this session various techniques for image optimisation will be explained, including when and where "auto colour/contrast/optimise" may be helpful. Also covered will be "big prints" - how to make optimum use of your pixels! In addition to the slides presentation (above) the author has also kindly supplied the notes that go with it.

Mike Tooms - Proving Colour Management is Working Well in Your System (4.2Mb PDF file)
Imaging Consultant
A project to identify the relationship between theory and practice at each step of the workflow from scene to print. The primary aim is to photograph a GretagMacbeth Color Rendition chart and produce a close visual match between it and the system monitor display and the resulting print. Equally important at each step in the workflow is to understand the theoretical basis of the setup menu options offered and to define the option required from amongst the often confusing array available in each element of the reproduction system, i.e. the digital camera, Adobe Gamma, Adobe Photoshop and the inkjet printer driver.

Ray Knight - The Final Link in the Imaging Chain (2Mb PDF file)
Photographer
The final step in the imaging chain is not the printer/display screen but the eye/brain complex. Fitting the reproduction of a real world scene into the "limits of a print" requires understanding of the dynamic range of the camera, and then the scene and lighting contrast ranges. The adaptation of the eye brings some formality to viewing conditions, and the white balance settings adopted especially when shooting outdoors. The various defects of a digital print such as pixels, tonal layering, compression artefacts and over-enhanced sharpness are looked at: it is hoped they remain subliminal.