topic Re: Issues with Facade lighting - Rendering, Aiming, Color in Revit Architecture Forum

Issues with Facade lighting - Rendering, Aiming, Color

Anonymous — Wed, 22 Aug 2018 00:04:35 GMT

Hey Guys,

Im new to Revit. Only at it for about a day but i am Familiar with other lighting software.

I am trying to create a rending of a Facade lighting project and am running into a few issues...

- I am unable to aim the fixtures effectively because i don't see that i am able to increase the length of the photometric web. The "Light Source Symbol Length" parameter does not show under type properties. The web only extends about 1' from the fixture. Any reason why this wouldn't show?

- I am unable to change the color of the light emitted from the fixture. I changed the color filter to a few different colors but nothing shows any different in the rendering. The only parameters that makes a difference in the rendering that i have seen are the "Initial Color" parameter and the "Lens Material Finish" parameter. Neither of these options give me much control at all over the light color.

- Some changes that i make do not show through in the rendering. Two examples: First, I created two separate lighting groups and turned one of them off to only show one portion of the building facade, the fixtures i turned off still show as on. Meanwhile a third group i created does stay turned off. Second, i have tried multiple ways to decrease the brightness of a fixture but nothing seems to make any difference. I have tried the dimming function under the rendering settings, I have tried lowering the light loss factor to 0.1, I have even tried manually decreasing the luminous flux. none of which worked. Is there a step you have to take every time in order to make whatever changes you made show through in a rendering?

Just some background on my model. I imported the fixture families from the manufacturer of the floodlights. i have attached the appropriate IES files. The building model itself came from the architect. See attached images for reference.....

Any help or guidance would be greatly appreciated.

Re: Issues with Facade lighting - Rendering, Aiming, Color

barthbradley — Wed, 22 Aug 2018 01:01:32 GMT

Are we talking total luminous flux or luminous intensity. Total luminous flux is the total amount of light emitted from a light source, corrected for the spectral response of the human eye to light. It is measured in lumens. The luminous intensity defines the amount of lumens in a given direction, per solid angle. This is measured in lumens per steradian, or candela. The luminous intensity in a photometric file will be defined in many different directions. A typical photometric file that we create at Photometric Testing will contain luminous intensity values for 855 different angles. A photometric data file will also contain the input electrical power that the light source consumes (the Watts).

Just kidding. None of that information will be on the final. However, this might -- and it may answer one of your questions regarding "aiming":

https://knowledge.autodesk.com/support/revit-products/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/Revit-DocumentPresent/files/GUID-8601EE39-481B-4CD0-B673-D9BFFA096FE6-htm.html

Re: Issues with Facade lighting - Rendering, Aiming, Color

Anonymous — Wed, 22 Aug 2018 01:58:52 GMT

Thanks for the quick reply.

Yes, im talking about Luminous Flux. I am using an IES file for the Photometric web, I adjusted the initial intensity using the Luminous flux option from almost 1000 lumens down to 500 lumens but no change in the light levels in the rendering. I then changed the Light Loss Factor down to 0.1 just to see if that would make a difference but nothing changed. Even tried to dim the fixture using the " Rendering settings -> Artificial Lights->Dimming (0-1) " feature but no luck.

The aiming issues i'm having are more related to fine tuning fixtures for grazing a wall. I'm lighting a wall that's 290' tall from between 8-16' away. so a degree or half a degree makes a huge difference. It would be great if i were able to fine tune the tilt angle by extending the photometric web up to 290' out to show where the center beam candela would land on the facade at each specific degree. I just don't see that its giving me that option.

Does using an IES file limit some of the additional changes you can make? Does it not allow you to a adjust the light source symbol length, luminous flux or color?

Re: Issues with Facade lighting - Rendering, Aiming, Color

barthbradley — Wed, 22 Aug 2018 02:47:06 GMT

@Anonymous wrote:
Does using an IES file limit some of the additional changes you can make? Does it not allow you to a adjust the light source symbol length, luminous flux or color?

Yes.

...perhaps "seeing" an IES file for what it is will be "illuminating".

Re: Issues with Facade lighting - Rendering, Aiming, Color

Anonymous — Wed, 22 Aug 2018 03:21:53 GMT

Lol!!! Terrible joke man.... take it from a lighting rep. Lighting jokes never end well. I may still steal that one from you though.

I was able to get a half decent rendering out of what i did. I need to be able to change colors though as the fixtures are RGBW. I was hoping Revit would give me better rendering functionality than AGI. seems like you gain some with revit but you also lose some functionality. Here are some I did just to show color from AGI....

Re: Issues with Facade lighting - Rendering, Aiming, Color

barthbradley — Wed, 22 Aug 2018 03:35:23 GMT

I'm not trying to contest you, Buddy. Sorry if I came off that way. I'm just imparting info to a complete stranger on the other end of the phone; if you know what I mean. No offense.

Re: Issues with Facade lighting - Rendering, Aiming, Color

barthbradley — Wed, 22 Aug 2018 03:44:20 GMT

you know what they call a bunch of IES files at the bottom of the ocean?

A good start.

Ha!

Re: Issues with Facade lighting - Rendering, Aiming, Color

Anonymous — Wed, 22 Aug 2018 03:54:50 GMT

@barthbradley wrote:
I'm not trying to contest you, Buddy. Sorry if I came off that way. I'm just imparting info to a complete stranger on the other end of the phone; if you know what I mean. No offense.

No, not taking it that way at all. I appreciate all the input. Bad jokes included!!!!