[stonelli]

It would be nice if the NL could deliver definitions of standard lamps like T5 at various wattages etc. etc.
Since the brief intro to one alludes to geometry manipulation these could be actual objects that one can add to the scene, maybe by swapping like used to be possible in lightscape (only played around with it a long time ago so I have no idea if that feature is still in there).
I ask because I know that lamp manufacturers have IES (and other) profiles of their lamps but they are only accessible to lighting designers, as far as I know.

[aitraaz]

yeah would be cool...

plus, a way of being able to measure luminance values in lux would be brilliant, i think NL mentioned the possibility of something like this down the road...

if one could get lux values out of a rendered image, maxwell would be more than viable as a lighting analysis instrument IMO...

[stonelli]

plus, a way of being able to measure luminance values in lux would be brilliant, i think NL mentioned the possibility of something like this down the road...

if one could get lux values out of a rendered image, maxwell would be more than viable as a lighting analysis instrument IMO...

Definitely

[Hugh]

I think this is actually unadvisable for NL to do. There are far too many variables involved in luminaire modelling for it to be simplified into lamps & housing. IES data isn't so good at capturing the close up details of a lighting distribution, but it's the best course to take when accuracy is important, as the radiance has been measured from an actual luminaire.

The problem with modelling the housing & source geometry is that things like temperature aren't accounted for. With T5 lamps, the optimum temp is 35 deg C, a drop of ten degrees and you loose 10 percent of the output and the running temperature of the lamp depend largely on the design of the housing.

The final illuminance on a given surface is subject to plenty of uncertainty as it is with variables such as reflection factors, voltage, maintenance factors, temperature, etc. So the start data should be as close to actual reality as possible.

I'm not say don't do it. I'm saying don't cry when your client goes mad because the lighting is off by 20 percent.

For Vizualisation, model the fitting. For lighting analysis, IES.

[stonelli]

I think this is actually unadvisable for NL to do. There are far too many variables involved in luminaire modelling for it to be simplified into lamps & housing. IES data isn't so good at capturing the close up details of a lighting distribution, but it's the best course to take when accuracy is important, as the radiance has been measured from an actual luminaire.

The problem with modelling the housing & source geometry is that things like temperature aren't accounted for. With T5 lamps, the optimum temp is 35 deg C, a drop of ten degrees and you loose 10 percent of the output and the running temperature of the lamp depend largely on the design of the housing.

The final illuminance on a given surface is subject to plenty of uncertainty as it is with variables such as reflection factors, voltage, maintenance factors, temperature, etc. So the start data should be as close to actual reality as possible.

I'm not say don't do it. I'm saying don't cry when your client goes mad because the lighting is off by 20 percent.

For Vizualisation, model the fitting. For lighting analysis, IES.

Hugh, thanks for your input. It's just that, how many times have you wished you had the actual lamp you envisioned using??
Maybe NL could include the variables that would affect lamp efficiency, or maybe maximum efficiency would be assumed.
As it is, unless they deliver some way to quantify the lighting in a scene, the program can't be truly used for lighting design so, possibly, your concerns are less relevant.

[Richie]

Hallo

Well, I think the Temperatur Factor is not a matter.
You can even think on Dirt and Ageing of a Lamp on whihc you loose 10%-30%, but you dont.

All Rendering is for optimal situation, but not for "wrong" temperature or old lamps

Richie

[stonelli]

Hallo

All Rendering is for optimal situation, but not for "wrong" temperature or old lamps

Richie

Yes, that is generally true