RevitCity.com Logo

Home  |  Forums  |  Downloads  |  Gallery  |  News & Articles  |  Resources  |  Jobs  |  FAQ  |  SearchSearch  |  Join  |  LoginLogin

Welcome !

48 Users Online (44 Members): Show Users Online - Most ever was 626 - Mon, Jan 12, 2015 at 2:00:17 PM

 

Forums

Forums >> Revit Building >> Technical Support >> Do you really trust Revit shadows?

Search this ThreadSearch this Thread | Page 1 of 2 | 1 | 2 Next >>

Wed, Aug 9, 2006 at 5:46:27 AM | Do you really trust Revit shadows?

#1

ivanvasc


active

Joined: Tue, Aug 16, 2005
24 Posts
No Rating


Have you ever check if the sun studies you perform in Revit really match the real shadow at your place? I did and they do not match. What could be wrong with my experiment? See the attached file e try to do the same. Tel me about your results.

This user is offline

 

Wed, Aug 9, 2006 at 7:56:30 AM | RE: Do you really trust Revit shadows?

#2

DesignerInSD


active

Joined: Wed, May 24, 2006
12 Posts
No Rating


Have you taken elevation into account? Are you showing your Revit model at true elevation? Solar time is affected by elevation due to the fact it is true bending of sunlight over the horizon.

This user is offline

 

Wed, Aug 9, 2006 at 9:43:38 AM | RE: Do you really trust Revit shadows?

#3

ivanvasc


active

Joined: Tue, Aug 16, 2005
24 Posts
No Rating


Even after changing the elevation, using the real local value (745 m) the shadows didn't match. They weren't affected by the change. The shadow is the same in both cases (elevation 0 m and 745m). In Revit, when we set up the geographic cordinates, there is no option to configure the local elevetion, is there?

This user is offline

 

Wed, Aug 9, 2006 at 10:53:03 AM | RE: Do you really trust Revit shadows?

#4

ArchWestCY


active

Joined: Wed, Mar 29, 2006
197 Posts
4.5 Stars: 7 Votes


Have you set True North? If your building is drawn with the top of the monitor as north, it may not be exactly True North. This will make a big differance. Also, check to make sure that the building is in the right location. Latitude and Longitude is more accurate than just picking the nearest big city. I have included the help file for True North, as it iisn't rreally simple to figure out on your onw. Location is easy, and shouldn't be hard to learn. "To orient a project to True North: In the Project Browser, open a 2D plan view of the project. You must be in a 2D plan view to set the view orientation to True North. Click View menu > View Properties. TIP:You can also right-click in the drawing area, and click View Properties to access the Element Properties dialog. In the Element Properties dialog, under Graphics, select True North for Orientation, and click OK. NOTE:You must change the view orientation to True North before you can rotate the project to True North in the view. Click Tools menu > Project Position/Orientation > Rotate True North. On the Options Bar, for Angle from Project to True North, enter a value to set the angle of rotation. For example, if the difference between Project North and True North is 45 degrees, enter 45 in the Angle from Project to True North field. The project rotates in the view to the specified angle. NOTE:Settings for project location and orientation, including the angle from True North, are saved with the project, not the view." Hope this helps ArchWestCY

This user is offline

 

Wed, Aug 9, 2006 at 11:53:50 AM | RE: Do you really trust Revit shadows?

#5

ivanvasc


active

Joined: Tue, Aug 16, 2005
24 Posts
No Rating


Thanks for the tutorial. Really to undestand the process of rotating true north is not that easy. But I had already done that. So, the model is correctly oriented. The True North is realy the top of the monitor. And now, what do I do? Have you ever check the shadows of your projects? They really match with the real ones?

This user is offline

 

Wed, Aug 9, 2006 at 12:28:56 PM | RE: Do you really trust Revit shadows?

#6

Zenoza


active

Joined: Mon, May 8, 2006
3 Posts
No Rating


Maybe its the difference between summer and wintertime clock settings.

-----------------------------------
ZENO-architects The Netherlands

This user is offline

 

Wed, Aug 9, 2006 at 3:09:43 PM | RE: Do you really trust Revit shadows?

#7

ArchWestCY


active

Joined: Wed, Mar 29, 2006
197 Posts
4.5 Stars: 7 Votes


So, if you already have True North set, I'm guessing that you have the location set as well. I saw that you have set the elevation to match your location. Wow, that's a melon scratcher. Are they significantly off? Could it be the Daylights Savings setting, like Zenoza suggested? Is your camera veiw set to True North. It is possable to have True North set, but your new camera view is still set to Project North. You typed that True North is the top of the monitor, does that mean that True North and Project North are equal? If so, that is pretty handy. I'm running out of ideas. Wow. I should have looked at you .pdf first. That looks like a really cool experament you have going. It does seem as though the daylight savings time setting could play a part, becuase the differances are not incredably significant. I hope you find a concrete answer. Keep me posted. Are you taking into account the declination for your area. True North vs. Magnetic North? ArchWestCY

This user is offline

 

Wed, Aug 9, 2006 at 5:20:53 PM | RE: Do you really trust Revit shadows?

#8

ivanvasc


active

Joined: Tue, Aug 16, 2005
24 Posts
No Rating


Oh...Declination beetween True and Magnetic North...Finally something I haven't tried yet...This can cause a visible difference. The angle between the shadow edges is about 19ยบ. I'll try that and I return the result to you...Thank for everybody's help...For a while....

This user is offline

 

Wed, Aug 9, 2006 at 5:30:47 PM | RE: Do you really trust Revit shadows?

#9

Mr Spot


site moderator|||
Mr Spot Avatar

Joined: Mon, Jan 12, 2004
2889 Posts
4.5 Stars: 93 Votes


I'd also suggest filing this with support. They will be able to explain how the revit shadows are calculated. I'm sure the factory would like to know if they are incorrect. File a support Request. It seems highly unlikely that a tool like this would be implemented that results in incorrect results.

This user is offline

View Website

Wed, Aug 9, 2006 at 5:34:43 PM | RE: Do you really trust Revit shadows?

#10

ivanvasc


active

Joined: Tue, Aug 16, 2005
24 Posts
No Rating


In the mean while, please answer: DID SOMEONE ALREADY HAVE THE CURIOSITY OF CHECKING THE SHADOWS? OR EVERYBODY TRUST BLINDLY ON THE MACHINE?

This user is offline

 

Wed, Aug 9, 2006 at 6:13:57 PM | RE: Do you really trust Revit shadows?

#11

ArchWestCY


active

Joined: Wed, Mar 29, 2006
197 Posts
4.5 Stars: 7 Votes


Trust Blindly. Thank You. ArchWestCY

This user is offline

 

Wed, Aug 9, 2006 at 9:21:56 PM | RE: Do you really trust Revit shadows?

#12

psymon


active
psymon Avatar

Joined: Sun, Sep 11, 2005
185 Posts
3.5 Stars: 6 Votes


I have replied to this post in the Autodesk Discussion groups where you have posted it. I agree that your problem is probably the differnece between True and Magnetic north. I have tested the shadows and they are accurate if you use true north. ( have not psyically checked them as you did, but the altitude and azimuth numbers correctly compare the those we have for manually calculating the shadows, and I have compared a manual shadow to a revit one and that match to within a degree or two.

This user is offline

View Website

Thu, Aug 10, 2006 at 5:42:32 AM | RE: Do you really trust Revit shadows?

#13

ivanvasc


active

Joined: Tue, Aug 16, 2005
24 Posts
No Rating


ALELUIAH! I'VE GOT IT. WITH YOUR HELP FOR SURE. THE ANSWER IS THE MAGNETIC DECLINATION. TRUE NORTH SHALL BE CHANGED BY A VALUE, IN MY CASE, OF ABOUT 19 DEGREES. THEN, THE SHADOWS MATCH! SO, WE CAN BLINDLY TRUST IN REVIT AGAIN. THANK YOU ALL FELLOWS!

This user is offline

 

Thu, Aug 10, 2006 at 8:03:09 PM | RE: Do you really trust Revit shadows?

#14

robert


active

Joined: Mon, Aug 30, 2004
89 Posts
No Rating


this is reassuring. i allready had visions of hungry lawyers knocking on my door because of neighbours getting more shadow that shown in townplanning permits. (most councils in australia require a shadow diagramme as part of a townplanning application) as this is so critical why can't revit put a warning on the dialog box with a reference to a tutorial? if the programme was that intuative, more people would know about this. the more they can support mere human beings like us the more chance there would be that we could actually start to like the clever chaps. next thing: how accurate is the shadow on a topo surface with a steep slope (incline) i wonder if ivanvasc could test it for us as he allready got a testing rig? thanks for bringing this to our notice

This user is offline

 

Fri, Aug 11, 2006 at 2:24:19 AM | RE: Do you really trust Revit shadows?

#15

eldados


site moderator|||
eldados Avatar

Joined: Mon, Mar 14, 2005
777 Posts
4.5 Stars: 8 Votes


glad to help Ivan Smile Post edited on 2006-08-11 02:24:41

-----------------------------------

Integrator

Architectural Engineering Construction

KarelCAD

This user is offline

View Website

Search this ThreadSearch this Thread | Page 1 of 2 | 1 | 2 Next >>



Similar Threads

Thread/Thread Starter

Forum

Last Post

Replies

Getting rid of shadows in Revit rendering?

Revit Building >> Technical Support

Sun, Dec 3, 2017 at 2:06:46 AM

6

Moving shadows in animations

Revit Building >> Technical Support

Thu, May 5, 2011 at 5:42:26 PM

2

Printing Shadows in .pdf file - Revit 7.0

Revit Building >> Technical Support

Wed, Dec 22, 2004 at 9:16:23 AM

2

Soft Shadows Revit 2015?

Revit Building >> Technical Support

Thu, Mar 17, 2016 at 5:35:16 AM

1

Revit shadows in rendering

Revit Building >> Technical Support

Thu, Jan 14, 2010 at 12:14:48 PM

1

Site Stats

Members:

1963264

Objects:

22843

Forum Posts:

152159

Job Listings:

3

Sponsored Ads

Home | Forums | Downloads | Gallery | News & Articles | Resources | Jobs | Search | Advertise | About RevitCity.com | Link To Us | Site Map | Member List | Firm List | Contact Us

Copyright 2003-2010 Pierced Media LC, a design company. All Rights Reserved.

Page generation time: 2.7631

Login

User Name:

Password:

Remember Me  

Forgot Password?

Search Forums

Advanced Search

Search Forums

Advanced Search


Clear Highlights


Clear Highlights