Seasonal Shadow Problem

see shadows - not sunset times

it appears to be out in the older version as well now but wasn’t before… Are sunrise/sunset times updated over the internet from somewhere of built in each version of software. 21st June should be longest day, 21 Dec shortest within a day or two - seems quite far out??

Have you correctly geolocated your model AND set the correct time zone? If you forget the latter, it will use the time zone of Boulder, Colorado and the sunrise/sunset times will be quite off for your location, especially if you are nowhere near the SketchUp headquarters.

There is a handy online sun position calculator at http://suncalc.net to check your SketchUp results against.

Anssi

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Sorry - can’t see my earlier reply. The shortest day is on or v close to Dec 21st - not early December. How can a piece of software for architects, created by Google get this fundamental fact applying to solar shadows completely wrong?!

Is there a fix?

Has anyone else noticed this?

FWIW, sunset does occur later on December 21 than it does on, say, December 7. You can look that up on Sunrise/Sunset calendars. Here it is for Boulder. Yes, there are fewer minutes of daylight on Dec 21 but that’s all due to sunrise time.

It looks to me as if the developers got it right.

Make a calendar for your own location and see what you get.

FYI, SketchUp was not created by Google and Google has had nothing to do with it for four years.

OK, fair enough… I take both your points - but the reason I thought it was out wasn’t just the number of hours of daylight. It’s my understanding that on the shortest/longest days the sun rises (or sets) furthest north and south of east (or west). So on my model, I’d expect to see the solar shadow limits on those days - not earlier?

Should be so.
Check sunset vs sunrise for your location on this site: http://www.timeanddate.com/sun/netherlands/dordrecht?month=12&year=2016
For me sunset is earliest on dec.12 / 2016 (16:31) and sunrise is latest on jan.2 / 2017 (8:48)
Shortest daytime appears to be on dec.21 (edit: for this year at least!)

Evidently no one told the solar system that it should work that way. :slight_smile:

Are you saying that in early December, in Boulder, you think the sun sets further south of east than it does on Dec 21st?

when is say east i mean west :slight_smile:

I didn’t say that.

I didn’t say that, either. All I said is that the sun sets later on Dec 21 than it does two weeks earlier in the month. I guess you can imply what you want from that but I didn’t mean anything more than I wrote.

And from your first post, the only thing that I see that needs to be address is your misconception of when sunset occurs throughout the year.

ok, all fair enough. But, my original point then, is not about the time (though I did think it would earlier), its about the shadow limit (which I think should fall in the solstices)?

i.e. shadows should reverse direction on Dec 21st not in early december.

Maybe you should do a little more research.

on what - when the sun reaches its maximum points - thats why we call them the solstices!!

Its a very simple question I have - why don’t the shadows change direction on the right day?

a lot of settings effect shadows…

can you supply your Template, for others to check your settings?

also, are you using a plugin to control the data collection?

john

not using any plug-ins (as far as I know)… all the ‘shadows’ ticked in the various menus and ‘use sun for shading’ which I’ve done before and it’s worked as expected i.e. shadows change direction on the solstices - hence my confusion?

As I said, you need to do some research. At noon you’ll see what you are expecting with the height of the sun at the slostice

i was talking about sunset sage :slight_smile: