If you can reach out and ask them what simulation engine they're using (e.g. Radiance) that would help let us know. There are two parts to trusting a simulation: 1) a validated engine / equation and 2) correct simulation inputs (not garbage). Start by checking the former :)
Hello everyone I'm the developer of Lumen Pro and Carlo asked me.
So far i received the values from experimenting with area lights with a spread angle of 0° which effectivly makes them have no falloff.
We were also able to confirm the values by building a real world room in 3D and by using the correct ies files for the actual lights and measuring with a lux meter in real world. The whole topic is quite complex and the ways from radiometry to photometry are not that simple.
( Blender might need some changes here too , which i'm hesitant to do as it would involve providing an extra Blender version ...)
Still i'm in contact with other developers to make sense of the math cycles uses and to build a solid base for measuring.
Hope that aswered your questions. If you have any futher questions or suggestions feel free to ask
and join my discord. https://discord.gg/Efjc6fCd
If you are a professional who has alot of experience with the math behind it feel free to contact me via pm as i'm still looking for beta testers
to make lumen pro the best it can be. you might also use my email ... info (at) q3de (dot) com
regard u3dreal
Hi all i try to get a baseline with dialux evo and relux ... but i can not get both to deliver any meaningfull / similar results ...
a simple room 5.8x3.6x2.8m with one luminaire in the middel ERCO Starpoint and a reference plane at 0.8m .. i get totally different results.
dialux
relux
luminaire
Can anyone explain these rather huge differences ? Or are 150 lux negligible ?? :)
dialux evo max 75lux
relux max 223 lux
Anyone willing to help me make some sense of this will not regret it
I can share the projects too.
Thanks
u3dreal
Hello @u3dreal, (in italy with heritage buildings of specific use) there are spaces where different areas are supposed to have lux 300, lux 250, lux 150, lux 200, lux 150, lux 200, lux 50, all in the same room; so, no, I do not think 150 lux are a negligible value...
Sorry I'm not able to help you with simulation engines... I guess there could be some problems with parameters input...
Hi carlo i double checked the luminaire settings and the wall reflectance and so on .. but it seems the whole topic is quite controversial ..
Can anyone give me an example where dialux and relux match ? I have Lumen matching dialux evo but due to Relux i'm confused.
Hi @u3dreal
I agree with @carlopav. 0 to 150 lx difference is not negligible. (To be more accurate, 150 to 300 is not negligible, but 5000 to 5150 IS NEGLIGIBLE.)
I have experience using Dialux evo (but not for Relux), so I am not sure how Relux works... Just to make sure, did you check the following parameters?
1. Reflectances of the ceiling and floor are equal to those of Dialux?
2. Height of the working plane = 0.8m?
3. Maintenace factor is equal to the one of Dialux?
Reflectances of the ceiling and floor are equal to those of Dialux?
Yes . 0.8
Height of the working plane = 0.8m?
Yes
Maintenace factor is equal to the one of Dialux?
Yes 0.8
Maybe i should just make sure Dialux and Lumen are the same.
It would help alot to have an actual project to test against.
If you are interested feel free to contact me.
Comments
Thank you for sharing this information. I am also curious about how it performs. Does Lumen Pro give us the same results as Dialux Evo does?
If you can reach out and ask them what simulation engine they're using (e.g. Radiance) that would help let us know. There are two parts to trusting a simulation: 1) a validated engine / equation and 2) correct simulation inputs (not garbage). Start by checking the former :)
Just asked!
Hello everyone I'm the developer of Lumen Pro and Carlo asked me.
So far i received the values from experimenting with area lights with a spread angle of 0° which effectivly makes them have no falloff.
We were also able to confirm the values by building a real world room in 3D and by using the correct ies files for the actual lights and measuring with a lux meter in real world. The whole topic is quite complex and the ways from radiometry to photometry are not that simple.
( Blender might need some changes here too , which i'm hesitant to do as it would involve providing an extra Blender version ...)
Still i'm in contact with other developers to make sense of the math cycles uses and to build a solid base for measuring.
Hope that aswered your questions. If you have any futher questions or suggestions feel free to ask
and join my discord. https://discord.gg/Efjc6fCd
If you are a professional who has alot of experience with the math behind it feel free to contact me via pm as i'm still looking for beta testers
to make lumen pro the best it can be. you might also use my email ... info (at) q3de (dot) com
regard u3dreal
Hi all i try to get a baseline with dialux evo and relux ... but i can not get both to deliver any meaningfull / similar results ...
a simple room 5.8x3.6x2.8m with one luminaire in the middel ERCO Starpoint and a reference plane at 0.8m .. i get totally different results.
dialux
relux
luminaire
Can anyone explain these rather huge differences ? Or are 150 lux negligible ?? :)
dialux evo max 75lux
relux max 223 lux
Anyone willing to help me make some sense of this will not regret it
I can share the projects too.
Thanks
u3dreal
Hello @u3dreal, (in italy with heritage buildings of specific use) there are spaces where different areas are supposed to have lux 300, lux 250, lux 150, lux 200, lux 150, lux 200, lux 50, all in the same room; so, no, I do not think 150 lux are a negligible value...
Sorry I'm not able to help you with simulation engines... I guess there could be some problems with parameters input...
Hi carlo i double checked the luminaire settings and the wall reflectance and so on .. but it seems the whole topic is quite controversial ..
Can anyone give me an example where dialux and relux match ? I have Lumen matching dialux evo but due to Relux i'm confused.
Hi @u3dreal
I agree with @carlopav. 0 to 150 lx difference is not negligible. (To be more accurate, 150 to 300 is not negligible, but 5000 to 5150 IS NEGLIGIBLE.)
I have experience using Dialux evo (but not for Relux), so I am not sure how Relux works... Just to make sure, did you check the following parameters?
1. Reflectances of the ceiling and floor are equal to those of Dialux?
2. Height of the working plane = 0.8m?
3. Maintenace factor is equal to the one of Dialux?
Yes . 0.8
Yes
Yes 0.8
Maybe i should just make sure Dialux and Lumen are the same.
It would help alot to have an actual project to test against.
If you are interested feel free to contact me.
implemented Instancing the light on mesh verts
RT Mode is in Lumen Pro now :)
