Shadows and true vs. project north

[christo4robin]

I love the advanced model graphics shadow feature! That said, I have a project in which true and project north are not the same. When I cast shadows in the view using the place and time option, it appears that Revit measures these from project north rather than true north. Can anyone confirm this? Am I missing something?

[Mr Spot]

I noticed there is a separate tab in the advanced model graphics under locations where you can define the angle between true and project north... Maybe it?

[christo4robin]

I'll check it out - thanks!

[LRaiz]

In order to place sun relative to true north I think you need to use By Date, Time and Place option in Sun and Shadow Settings dialog. Using Directly option places the sun relative to project north (if checkbox is off) or relative to view (if checkbox is on).

[christo4robin]

Leonid and Mr Spot, thanks for the replies. Shadows are casting as I would expect based on project north. I'm wishing to be able to cast shadows relative to true north. So far no luck figuring out how. Any other suggestions?

Grazie!

[hand471037]

4-to-the-C, have you rotated this project using the 'Rotate / True North' tool under settings? We're having a simular issue here, yet on one project that was properly rotated it was fine, on another it seems like it's not having an effect- but we haven't had time to look too closely at it. :/

[Scott D Davis]

same problem here....using Rotate Project/True North has no effect on shadows, when adjusting True North should change the shadows.

[christo4robin]

Jeffrey,

Yes this project has been rotated project north / true north are different. Shadows are cast relative to project north (using place, date, time) and I have not found a way to get them to cast relative to true north.

Workaround idea - refer back to the old school texts with altitude, azimuth tables at different latitudes - then use that to manually create correct shadows.

Cheers!

[LRaiz]

I played with Sun and Shadows dialog a bit and as a result edited my previous post to make it more precise. The behavior I observe suggests that

(A) If you select "By Date, Time and Place' option then sun/shadows are placed accordingly and everything is computed relative to true north.

(B) If "Directly" is selected and check mark is off then sun/shadows are placed relative to project north.

(C) If "Directly" is selected and checkmark is on then sun/shadows are placed relative to view up direction.

Makes sense?

[hand471037]

huh- ok, I'll have to double check the one that I thought was working. thanks for the heads up, 4C.

[christo4robin]

The project I've been struggling with is one I brought up from 6.1. I'll go through your sequence again to see if I can tweak it into working.

[hand471037]

just wanted to point out again just how much shadows rock. :D

thanks for making my work look that much better...

[christo4robin]

Second to Jeffrey's "shadows rock!". Now if I can just figure out what I'm missing...

Here are a couple of images to show what I've got set up.

TIA,

Christopher

[FK]

Is it me, or is the dialog saying True North is 105 deg West while the arrow is pointing East?

[LRaiz]

The only other thing to check is to make sure that in Advanced Model Graphics dialog the correct Sun and Shadows setting is chosen. If there is no mistake there then get in touch with support and ask them to pass the model to developers for investigation.

[christo4robin]

FK,

Here is a screenshot of the same site plan with the view orientation set to True North. Also, project north is 105 degrees west of true north. Any thoughts?

[tarch]

FK,

Here is a screenshot of the same site plan with the view orientation set to True North. Also, project north is 105 degrees west of true north. Any thoughts?
If I am not mistaken, shadows on both sheets are identical. Also, being in northern hemisfere, 10AM shadow on June 21 shall cast from east to west roughly and that's what your studies are showing. Right?

Alek

[FK]

Shadows shouldn't point south, that's for sure. Let's look into it tomorrow.

[ita]

Chris, I am having a similar result. The shadows relate to project north and not true north. No matter what changes are made to true north, the shadows relate to project north in both the true north and the project north views.

Initially I thought it may be a result of the model being upgraded to 7.0 from 6.1 - however if I do a simple model in 7.0 from scratch - I get a similar result!

Fedor, a further look at this would be very welcome.

[mmodernc]

Same here. No matter what I do shadows remain relative to project north even in the view set to true north. I am trying the link with Accurender North and true north setting but it does not seem to exist i.e. I change true north and the Accurender sun bearing remains the same.
I am not clear on what "use sun and shadow settings" in Accurender settings dialogue box does.

Also when you set up a view, say a section, to see what shadow a neighbour upsun casts on a subject wall downsun the shadow from the upsun building disappears.

This shadows feature should be big breakthru for those of us who have to do umpteen shadow studies for a one room extension.

[mmodernc]

maybe there needs to be a "relative to view" checkbox for "by date time and place" settings

[mmodernc]

As a workaround you could probably do a reverse rotation and physically rotate the whole project to true north while view is in project north and rotate it back to square on using the location and coordinates menu while in the true north view- I think we need a thorough tutorial on all sun shadow features.

[mmodernc]

The problem with the work around is anything that does work with true north such as property line segment tags will give an incorrect reading which is ok if you do a save as of the project for shadow diagrams only.
This is very confusing. I am assuming that this problem has been sent to revit support. signing off.

[FK]

Yes, please expect the fix in the next build of 7.0... No, I don't know when it's going to be available.

[beegee]

No, I don't know when it's going to be available.

Friday....... :)