HET609 Astrophotography & CCD Imaging
Credit Points:12.5 Duration & Workload:
One semester, equivalent to a 5 contact hour per week lecture course Prerequisites:
HET603 Exploring Stars & the Milky Way, introductory tertiary-level mathematics & physics (or equivalent) Aims:
This unit will discuss the principles behind the imaging of astronomical objects with telescopes, conventional cameras and CCD cameras, plus the use of computer techniques for image processing. It will focus particularly on techniques and equipment within reach of the (existing or intending) serious amateur astronomer. Content:
- Properties of astronomical targets: point and extended objects, point and surface brightness, spectrum distribution, sky brightness, atmospheric emission and scattering, motion of object (real or due to Earth), variable stars, supernovae and novae
- Principles of telescopic imaging: optics, aperture size, focal length, F ratio, field of view, magnification, resolution, aberrations, distortion of field, contrast, spectroscopy, tracking and control
- Principles of photographic imaging: SLR operation, lenses, specialised camera bodies, wide field (no telescope) use, 50mm, telephoto & wide angle lenses, filters (eg broad, H alpha etc), focal plane & eyepiece projection, vignetting
- Film properties: sensitivity, contrast, grain, colour sensitivity, print or slide, exposure time, film data sheets, gamma curves, use of b/w exposures with tricolour filters, special effects
- Film processing: development, printing, superposition of images, photographing photographs to enhance contrast, practical procedures for unsharp masking, 'pushing', hypering, noise reduction techniques
- Photometry and colours: spectral distributions; atmospheric extinction, dispersion & seeing; filters, standard photometric systems
- Principles of CCD imaging: principles, spectral range and sensitivity; digital, integrating & video cameras; DIY construction, computer requirements, pixel size and binning, exposure time, dark frames & flat fielding, remote telescope use, reduction of photometric data, reduction of spectroscopic data, images from the Internet
- Principles of CCD data reduction: software, dark frame subtraction, cosmic ray removal, flat fielding; brightness, contrast, greyscale, colour contouring, negatives, resizing, pixel editing, filters, unsharp masking; scaling, histogram, equalization & noise reduction techniques
This unit will be presented in on-line delivery mode, with contact via newsgroup and e-mail. Assessment Method:
Assessable newsgroup contributions, assignments and project. Textbook:
For information about the textbook, follow this link