ISSN: 1546-962X
CODEN: JAIOAD
Published Online: 10 May 2004
Page Count: 11

Seeing and Photographing Your Visual Observations

Petermann, MA
Consultant, Wiss, Janney, Elstner Associates, Inc., New York, NY

(Received 21 August 2002; accepted 17 September 2003)

Abstract

Light can play tricks on your eyes. Deficiencies that are observable at 1:00 PM are not necessarily observable at 3:00 PM. Depending on the nature of the light, sunlight vs. daylight, an inspector may or may not observe a bowing stone panel. Depending on the building facade material, configuration, or texture, light may or may not illuminate a facade deficiency. Ornate facades cast shadows in sunlight. A crack or spall can be lurking in those shadows. The inspector's choice of binoculars, experience, and possibly his psychological disposition may influence whether or not he observes an existing facade deficiency. Recognizing the deficiency may truly be a challenge, but photographing the deficiency may be a greater challenge. The crack or spall that lurks in the shadow on a sunny day may be nearly impossible to photograph. Excessive sunlight that reflects off the facade may wash out a photograph. Automatic cameras typically grab all surrounding light for a photograph, but this may be too much or too little depending upon the item to be photographed within the frame. The ability to set your camera manually may be necessary. This paper discusses the nature of light and suggestions for observing building facades and for recording deficiencies.

Keywords:
light, sunlight, daylight, tangential light, borescope, single reflex lens cameras, shade, shadow, facade ordinance

Paper ID: JAI11161
DOI: 10.1520/JAI11161
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