Monitoring light

We are a private gallery, and would like to learn few preventive
conservation skills. Could anyone help me for the following problem?

    1.  How many times should we take light reading each day? When
        is the best time?
    2.  What is the difference between vertical light reading, and
        horizontal light reading?
    3.  How can we calculate the LUX/Hour for yearly display time?
    4.  How can we prevent an incorrect light reading problem by
        human mistake?
    5.  What are the important components of a light reading record
        form?


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                  Conservation DistList Instance 16:34
                 Distributed: Friday, November 22, 2002
                       Message Id: cdl-16-34-028
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