Notes from IEEE IPCC99 Conference
New Orleans, Louisiana, September 7-10, 1999

Images and Audiences

Presenting Complex Technical Material to the Generalist Audience via Multimedia: A Case Study of Best Practices from James Burke's Connections Series

Candace Soderston
IBM Corporation

Session Description: This session featured several excellent video clips from BBC broadcaster James Burke's highly acclaimed Connections series. A major message is that less is more when it comes to multimedia techniques. We are armed with enough special FX at this point to destroy our communication altogether...clearly, we should not do that! Judicious use of technology is much more effective than electronic exhibitionism.

• 6 studies, 1990-1992: comparison of generalist adult audience learning patterns in traditional classrooms versus via interactive multimedia (Adams, Greg L.)
   
• 55% learning gain with interactive multimedia
• 25-30% higher retention rate (after 30 days)
• There is a tendency to overuse a new medium when it first hits the scene; this has been the case with multimedia. Practice in interactive multimedia is still in its infancy; we need to learn to apply our technological capabilities more judiciously.
• Effective practice in video/film is more mature and principled today than it is for interactive multimedia. Both media draw upon the same basic skill set: scriptwriting, graphic design, animation, music, etc.
• James Burke: M.A. English, began in teaching, worked into broadcasting (BBC); Honorary Fellow in STC, 1998.
• Connections 2 was a 20-episode series on the progression of human knowledge, the history of scientific invention. Thesis is the unpredictable effect of one idea upon another, the causal links.
• 3 arts of language: grammar, logic, rhetoric. Rhetoric includes invention, arrangement, style, and delivery.
• Arguments: purpose (deliberate = to persuade, forensic = to defend, epideictic = to entertain or inspire); appeal (rational, emotional, ethical); rational (inductive, deductive)
• Arrangement: attention demands a "hook" to get attention. Burke was a master of effective openers.
• Video clip: labyrinth of hedges, a 200-year-old dream that failed, or did it?...cut to sign of New Harmony.
• Video "white space"...seconds of just looking or listening to background noise/environment or action, intended to slow the pace.
• Straight cuts are cleaner than special FX such as wipes, fades, etc.
• Video clip: Dutch East India Company went north to try to find an alternate route to the Far East, avoiding the Portuguese (South American route) and Spaniards (African route) to the south...they failed, of course, hitting the polar ice cap. This opener uses successive disclosure, heavy use of schemes, tropes, and emotional appeal.
• Video clip: Singapore opener uses cross-cutting, parallel cutting, and elliptical cutting to collapse a 4-decade historical sequence.
• Video clip: The California Gold Rush cuts sharply to the Yankee Clipper, the fastest ship in the world, and then back to the Gold Rush.
• Uses both high tech (animation) and low tech (physically drawing on an old map with a magic marker).
• Endings: Burke often completed a full circle back to the beginning; same context, with a variation on the thesis statement (no formal good-bye)...outstanding example in New Harmony clip...transistors made of germanium from rocks near New Harmony made possible the Internet, which may one day make possible the intercultural tolerance which Robert Owen's 1820's socialist utopian experiment there failed to achieve.

Digital Image Resolution: What it Means and How it Can Work for You

Anne Anderson-Lemieux and Eva Knoll
Speedware Corporation

Anne Anderson-Lemieux is a graphic artist and electronic publications specialist with Speedware Corporation. Eva Knoll was educated in architecture but switched to graphic arts. She is "Webmistress" of the Speedware corporate Web site.

Session Description: Speedware is a software development house with business intelligent software. The presenters are graphic artists who help them with their images. The session was a good tutorial for an editor (or a graphic specialist with limited Web design experience) concerning proper handling of Web graphics. It stresses the importance of and summarizes the procedures for achieving proper resolution on graphics for different end products (printed, online, Web).

• Two types of image files are pixel-based (tiny squares) and vector-based (geometric formulas). This presentation focuses on pixel-based images.
• Pixels in a graphic image can change their size.
• Resolution = pixels per inch (ppi)in an image.
• "Jaggies" = pixels showing on an image when printed; they result from having insufficient resolution to print...not enough pixels per inch for the eye to create a smooth line.
• Web images are only 75 ppi; printed images need 300 ppi: WYSINWYG.
• Why can't you differentiate high-res vs. low-res on screen the way you can in print? Light blends a lot easier than ink. Also, colors of light are airy and clean--they will make an image appear brighter on screen. Ink is dirty and grimy and will make a printed image appear more dull.
• An 8.5 x 11 image at 300 ppi in .bmp format is ~24 MB. That same image at 75 ppi is only 1.5 MB.
• Decreasing image size increases ppi, thereby increasing resolution; vice versa for enlarging.
• 3 steps to proper resolution:
   
• Scanning
• Resampling for proper output and to decrease file size
• Printing
• Scanners take samples of color from an image and compose it into an image file. It is best to scan at 400%, larger than you need, and then scale down.
• Resampling: If you change the image size while holding ppi constant, you are resampling; when you do that, information thrown out (bicubic, bilinear, or "nearest neighbor," or color-based) of the file is permanently lost. The moral: always make a copy of the original before resampling. Try to use resampling only when going from high-res to low-res; it generally won't work for the reverse. Computer will try to do that, filling gaps with information that doesn't exist; therefore, the GIGO principle kicks in.
• Printing: a professional printer is 2400 dots per inch (dpi); standard office printer 300-720 dpi, laser printer 85-200 lines per inch (lpi).
• Color models: know when to use which, and how to minimize file size while still maintaining acceptable image quality.
• HSB model = hue, saturation, brightness.
• RGB = additive model (red, green, blue light)... for screen.
• CMYK = subtractive model (cyan, magenta, yellow, and black)... for print.
• 16 million colors: 8-bit color model (RGB each has a range of 256 intensities. 256 cubed = 2 to the 8th power = 16,777,216 colors).
• File sizes with 16 million colors can be excessive.
• Solution is indexed, predefined palette: 256 colors. Unfortunately, PC and Mac palettes are not identical.
• For cross-platform color compatibility, a reduced palette of 216 colors is used... eliminating the incompatible 40 hues that don't match from the PC to Mac palettes.
• Line drawings can use an indexed exact file, for system or Web.
• Photos need to be indexed adaptive or be unindexed if possible.
• Indexing color is analogous to resampling to reduce ppi. Objective is to reduce file size.
• Use vector-based graphics rather than pixel-based for making .pdf files. CMYK images for print cannot be .pdf'd without first being indexed (TIFFs).
• Summary
   
• Don't use Web graphics for print... resample to 75 ppi for online or Web: use RGB color model.
• Always scan bigger than you need. You can always go down in resolution, but you can never go up.
• Resample file for print quality (300 ppi - CYMK or indexed color model)...be sure to save original print files, and maintain separate images archived for print and online (high- and low-res, unindexed or indexed adaptive vs. indexed exact).