Effect of settings of digital fisheye photography to estimate relative illuminance within forest under low light conditions

Kazukiyo Yamamoto, Kenji Kobayashi, Toshiro Nonoda, Akio Inoue, Nobuya Mizoue

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

In order to evaluate the effects of settings of digital fisheye photography on estimates of relative illuminance (RI) within a forest under low light conditions, we assessed the effectiveness of some estimators, i. e., canopy openness (CO), sky factor (SF), and diffuse transmittance (DIF). The estimates were calculated from digital hemispherical photographs taken with two different exposure settings, i. e., the reference exposure setting and the auto-exposure setting. We also presented a new estimator (%Exposure), which does not require image analysis, and compared it with other estimators calculated from a digital hemispherical photograph using image analysis. The CO, SF, and DIF calculated from digital hemispherical photographs taken with auto-exposure setting were not significantly correlated with RI. However, those calculated from digital hemispherical photographs taken with reference exposure settings were significantly correlated with RI. On the other hand, %Exposure showed a slightly higher correlation with RI compared with the other estimators.

Original languageEnglish
Pages (from-to)283-288
Number of pages6
JournalJournal of Forest Research
Volume15
Issue number5
DOIs
Publication statusPublished - Mar 10 2010

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digital images
photography
photographs
transmittance
photograph
automobiles
image analysis
canopy
exposure
effect

All Science Journal Classification (ASJC) codes

  • Forestry

Cite this

Effect of settings of digital fisheye photography to estimate relative illuminance within forest under low light conditions. / Yamamoto, Kazukiyo; Kobayashi, Kenji; Nonoda, Toshiro; Inoue, Akio; Mizoue, Nobuya.

In: Journal of Forest Research, Vol. 15, No. 5, 10.03.2010, p. 283-288.

Research output: Contribution to journalArticle

Yamamoto, Kazukiyo ; Kobayashi, Kenji ; Nonoda, Toshiro ; Inoue, Akio ; Mizoue, Nobuya. / Effect of settings of digital fisheye photography to estimate relative illuminance within forest under low light conditions. In: Journal of Forest Research. 2010 ; Vol. 15, No. 5. pp. 283-288.
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