Can't get the photogrid to work...

[Turner]

Hi all-

Can anyone point me to a tutorial to getting the photogrid to work?

I've tried a bunch of different things.

Ultimately, I'd like to use an .ies see the results on the grid... I can get everything in place and see that the light is working properly when I render the floor... however, no changes appear in the photogrid.

thanks,

Andrew

[klinzey]

The photo grid does not use rendered lights it only used Spotlight Lighting Devices. The photometer and the photo grid do a simple distance squared cosine fall off calculation based on the center weighted peak candelpower of of the lighting device. It does not take into account any of the rendered lights, IES files, Color, intensity, shadows or geometry in the document.

To use the photometer or the photometric grid you need to place a "Lighting Device" in the document, assign a focus point and then place the photometer.

[Turner]

Hi Kevin - thanks -

I actually tried that first; maybe I didn't have the instrument aimed properly. Will try again.

Cheers,

Andrew

[klinzey]

There is also an option in the photomater to "Calcualte using only visible beams", turn it off to start with.

[dslodki]

Hi all...I'm working in VW2010 and Spotlight with Renderworks and trying to calculate photometric data from lamps in the "electrical accurate lamps" library. I've converted a 4' fluorescent tube into a lighting instrument, it turns on and off just fine, and renders nicely. However, I can't seem to get the photometer to work on this light, which is rendering light just fine. What give? I've even made a focus point for this light, and "focused" it on it and the photometer still reads a big goose egg. It's sort of important for me to figure this out, as we are building some lighting units to be used in filming. I've messed around with line lights, with grouping the line light with the fluorescent tube symbol and then converting them, nothing seems to work.

Any help would be ideal...

Dave

VW2010 Spotlight with Renderworks

[klinzey]

Again....

The photo grid does not use rendered lights it only uses Spotlight Lighting Devices. The photometer and the photo grid do a simple distance squared cosine fall off calculation based on the center weighted peak candelpower of of the lighting device. It does not take into account any of the rendered lights, IES files, Color, intensity, shadows or geometry in the document.

To use the photometer or the photometric grid you need to place a "Lighting Device" in the document, assign a focus point and then place the photometer.

The calculations are based on the data in the "Light Info Record" and the relation between the focus point and the lighting device.

[dslodki]

Thanks to your earlier posts, Kevin, that's exactly what I did, I've created a lighting instrument in Spotlight, and attached a light info record. And although one would hope that the symbol I've used, the T8 fluorescent tube from the accurate electrical library, which lights up just fine as a symbol, would attach the data to the light info record, it doesn't seem to be the case. So, I've gone and added a wattage of 100 to the light info record and a candlepower of 2700 (a rough lumen to candlepower ballpark...just for good measure but really just to enter a value) in the L.I.R. and still no output to the photometer. I can draw a beam and everything (although this beam is a directional light instead of line light). I've even laid in a photogrid, and then added a nook light just to make sure I've not completely lost my mind and that all works fine. However, I don't seem to get any measurable output from the fluorescent fixture. (A somewhat annoying thing about the photometer is that it seems it will read a light any time it has a focus point REGARDLESS if it's turned on or not in the visualizer. I suppose this can be handy, but it seems counterintuitive to have to delete focus position data from the OIP (or the focus positions themselves!!) when it's much easier to "turn off" the light in the visualizer.)

But I stray from the problem at hand. I'm trying to read the photometric data from some lighting fixures which contain 40 4' fluorescent tubes each. There are 3 of them, so we're dealing with 120 individual tubes. The data must be accurate, not just "to eye" in a render. Any help would be ideal... In fact the photogrid would be even more ideal than the photometer, however, that's not responding to my focused Spotlight lighting instrument either.

Thanks for your help, I look forward to your reply,

Dave

[dslodki]

And I apologize for being yet another photometer/dead horse beater, I've read the other photometer posts and thoroughly understand the concept, but I hope you agree that the idea of using it with a diffuse fluorescent fixture/line light is a different approach than using a lamp that emits a beam. Also, the photometer, if I can get it to work, would be a huge win, because if I have 120 4' tubes and I try to render it for even a ballpark "look", it's about 40 minutes to an hour on my quadcore 2.66G Mac Pro. My only other option is to export to ESP Vision for a somewhat hamfisted render and then I lose the ability to quickly and easily edit the lighting setup.

Thanks again for your help,

Dave