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View Full Version : Daylight saving and solar studies



mschroeder
2007-02-17, 09:54 PM
Sharing an insight.

After exporting an animated solar study (365 days @ 12:00), I noticed the cast shadow was abruptly jumping at points in the animation. Intuitively I thought a point in the shadow would trace a graceful curved figure eight like shape. I flipped the animation frame by frame until I came to a point when the shadow jumped. The date was March 11th, and the other November 4th. You're right, this coincides with daylight saving time adjustments for 2007. This explains a jumping animation. Looking closer though, the animation was printing a time at 13:00. So you can infer indicated time is solar time with no daylight saving time adjustment. Keep this in mind when using animated solar studies; the printed time is not daylight saving time adjusted, but the shadow is.

PS.
Daylight saving adjustment makes sense, but for my immediate purpose, analyzing shadow paths with subtle design adjustments, I would like to be able to turn it off. Now I'm having to export two animations and splice them together.

MTristram
2007-08-24, 04:53 AM
So you're saying Revit takes in account of Daylight saving in the States, so what do we from Down Under need to do to ensure our Sun/Shadow Studies are correct?

We go forward an hour on 30 Sept and back an hour on 6 April.