Light Scalloping & The Revolve Tool

[cek]

This question is not really about light scalloping but in the attachment the light profile on the wall is resulting from the construction of the light fixture.

The problem appears to reside in the resolution of the revolve at small diameters. The pendant fixture has about a 4 inch diameter opening and the revolve breaks down the 360 degree pass into 15 degree facets. I can't find a control for increasing the facets or reducing the degrees in each facet. I would suspect that as the diameter increases the facet arc's reduce to something less than 15 degrees.

Is anyone aware of a control for resolving this issue?

[trombe]

This question is not really about light scalloping but in the attachment the light profile on the wall is resulting from the construction of the light fixture.

The problem appears to reside in the resolution of the revolve at small diameters. The pendant fixture has about a 4 inch diameter opening and the revolve breaks down the 360 degree pass into 15 degree facets. I can't find a control for increasing the facets or reducing the degrees in each facet. I would suspect that as the diameter increases the facet arc's reduce to something less than 15 degrees.

Is anyone aware of a control for resolving this issue?

Sorry , I am not aware of any specific control for this.
You can avoid this problem though.
Revit was not designed / modified to provide for a smaller item level of precision (as yet) however, you should try other fixtures because you can get, more correctly shaped washing.
4" diameters are widely used all over the world and in Revit for some years without it being a disaster always although agree its not like a commercial rendering application.

Another option is to try IES lighting files (despite your very clear description above), or at least check the bulb settings etc.
Also, play with Finish.

[cek]

Ran some tests and it appears the pyramidal point of the light scallop on the wall may be related to the Spot Field Angle. After making several adjustments to the cone Spot Field & Beam angles with no improvements I dropped the spot light source point just outside of the fixture geometry and got the image results as attached.

Also noted that when I changed the Spot Field Angle value the light scallop on the wall did not change. The Spot Beam Angle seems to be working ok. So it doesn't seem to be the fixture geometry although I still have an issue with the faceting resolution.

I also noted that material changes in the family are not overwritting the values in the project, forcing me to unload the family, delete the related materials and then reloading the adjusted family into the project.

[etboards17]

Quick Question: Is the Light Source up inside of the geometry?

If so, I would suggest bringing the light down to the bottom of the fixture and using the parameters and or IES Light Webs to control how the light works.

I went through this scenario in the rendering included and quickly saw that I should not control the light shape by the geometry in the families

[mhenderson]

I agree with ET. You should move the light source outside of the shade. If you don't have an IES file you should be able to adjust the photometric parameters in the type properties of the fixture family. If your Light source is a downlight you should have parameters for Spot Field Angle and Spot Beam angle. Try playing with the angle of those to get the right amount of light on the wall.

Adding to the number of facets in your fixture can start adding to your render time too, especially if you have an already complex model to render from.