Start Date | Start Time | End Date | End Time |
---|---|---|---|
03/20/2006 | 1820 | 09/29/2006 | 0945 |
Subject: | NIM/TSI/M1 - Shadowband Misalignment |
DataStreams: | nimtsiskyimageM1.a1, nimtsimovieM1.a1, nimtsicldmaskM1.a1 |
Description: | From installation, the shadowband was positioned south at solar noon until the vernal equinox when it began to migrate counter-clockwise until reaching east 37 days later on 4/26 (about 9 days before mid-spring). The shadowband at solar noon continued to migrate until reaching its most northerly position (~15 deg) on the summer solstice (if everything was perfectly aligned, it probably would have been pointed north on this day). It then began to migrate clockwise and reached east again 56 days later on 8/16 (about 14 days after mid-summer). As expected, the shadowband reached its most southerly position on the autumnal equinox but was about 10 deg off of being due south. With the apparent alignment problem, I don't understand why the shadowband was mostly blocking the sun. When I started noticing this offset in May, I chose to leave it alone because I felt that adjusting the shadowband to where I thought it should be would cause it to not block the sun at either sunrise or sunset. The alignment was corrected on 9/29 (6 days after the day of the autumnal equinox). |
Suggestions: | |
Measurements: | nimtsiskyimageM1.a1: more
nimtsicldmaskM1.a1: more nimtsimovieM1.a1: more |