Coherence Principle 2: Avoid e-Lessons with Extraneous Graphics

Clark and Mayer (2011) recommend against the inclusion of pictures in instructional multimedia that do not directly relate to instructional content. They report that extraneous pictures can interfere with the learner's attempts to make sense of the material presented (p 159). They report that extraneous pictures (an their text captions) interfere with earning because they become sources of distraction, disruption and seduction (p 161). By seduction they mean that the pictures can trigger existing knowledge tending to create incorrect neural associations between the new material and existing knowledge. Clark and Mayer recommend that when graphics are used that the graphics be simple so as to not overload working memory.

Source: Understanding Exposure, 3rd edition by Bryan Peterson

I would argue that while instructional multimedia about learning to produce photographs for instructional purposes is likely to be full of photographs, the inclusion of many photographs are not likely to be a violation of Coherence Principle 2. So long as a photograph in such a book or online medium is included for the purpose of illustration rather than decoration, it is a needed design element. Brian Peterson's books available at Amazon.com and other book sellers.

References

Clark, R. C. & Mayer, R.E. (2011). E-learning and the science of instruction: Proven Guidelines for consumers and designers of multimedia learning. San Francisco: Pfeiffer.

Peterson, B. (2010). Understanding Exposure, 3rd ed: How to shoot great photographs with any camera. New York: Amphoto Books.