Accurate, real world lighting and exposure?

[james_conkle]

Why not go by eye? Especially since we’re getting false color soon. I could understand a need within technical architectural visualization but beyond that one would go by eye anyways, no? It’s not like when I’m on a set I say I need a 2k and that’s that. You’re referencing by eye what’s on the monitor, scopes and such.

[Lewis]

Why not go by eye? Especially since we’re getting false color soon. I could understand a need within technical architectural visualization but beyond that one would go by eye anyways, no? It’s not like when I’m on a set I say I need a 2k and that’s that. You’re referencing by eye what’s on the monitor, scopes and such.

Because IF you are loading IES file you are obviously trying to go accurate a spossible so why go by eye in that case if accurate is better ?
Changing/adding tha to Lumens/Candela won't delete option to go "by eye" but sometime "by eye" is just not enough .

Simple as that.

BTW, JayRoth , thanks for help, I fully understand you are not arguing agains lumens, appreaciate your help here.
But many people do not understand the need for it and think if they do not need it nobody needs it. I have "professional deformation" for light accuracy since i worked 10 years in LightDesign industry so i used Dialux/Calculux and precise Light calculation/renders for real world projects before they are built but hey it's always good to have precise way if possible. 3DS MAX reads IES/LDT light values, LightWave also (sicne 2018) so it is possible .

cheers

[pcoombes]

I'm not arguing against a lumens-based UI, but that is not what we have today. I am trying to help you get to where you want to go with this using the existing toolset as it is.

Fully appreciate your help.

So far bepeg4D's work-around seems to do the trick, ie put the required lumens value in the power setting and use a floating point value in the Texture slot to control the 'efficiency' he uses a value of 1/683 = 0,001464. These values and the correct .ies file seem to mimic the real world rather well

I appreciate this is fairly specific to arch vis, but accurate lighting is a must (architects and interior designers are demanding task masters!). It's almost impossible to do things by eye when you have multiple lights undertaking specific lighting tasks (ceiling spots, wall washes, task lights, concealed lighting, etc.) with multiple intensities and temperatures. You end up going round in circles, rendering and re-rendering over and over again.

Now then, what about these camera settings?!

[lanklaf]

I'm not arguing against a lumens-based UI, but that is not what we have today. I am trying to help you get to where you want to go with this using the existing toolset as it is.

Fully appreciate your help.

So far bepeg4D's work-around seems to do the trick, ie put the required lumens value in the power setting and use a floating point value in the Texture slot to control the 'efficiency' he uses a value of 1/683 = 0,001464. These values and the correct .ies file seem to mimic the real world rather well

I appreciate this is fairly specific to arch vis, but accurate lighting is a must (architects and interior designers are demanding task masters!). It's almost impossible to do things by eye when you have multiple lights undertaking specific lighting tasks (ceiling spots, wall washes, task lights, concealed lighting, etc.) with multiple intensities and temperatures. You end up going round in circles, rendering and re-rendering over and over again.

Now then, what about these camera settings?!

+1
Camera Exposure of 1 = ???

[lanklaf]

Here you have an xpresso of "real" camera in octane:




Adjust F-Stop, then ISO.
Then treat new Exposure as a shutter speed.

P.S. F-Stop does not affect the bokeh effect.

This is an old xpresso written by Marcus, I just made it work with the new Octane
and made a few adjustments.

[pxlntwrk]

Here you have an xpresso of "real" camera in octane:




Adjust F-Stop, then ISO.
Then treat new Exposure as a shutter speed.

P.S. F-Stop does not affect the bokeh effect.

Thanks for that, but its just another way to just setup exposure.
As long as the Aperture is not independent from the F-Stop in Octane, we will be in the cabbage

[lanklaf]

Here you have an xpresso of "real" camera in octane:




Adjust F-Stop, then ISO.
Then treat new Exposure as a shutter speed.

P.S. F-Stop does not affect the bokeh effect.

Thanks for that, but its just another way to just setup exposure.
As long as the Aperture is not independent from the F-Stop in Octane, we will be in the cabbage

Khm, but aperture should work with the F-stop,
this is exactly how camera works.

I changed the Exposure Value to Shutter Speed Value in Xpresso.
Default values are:
Shutter Speed: 1/50
F-Stop: 2.8
ISO: 100

If you want to simulate a real camera, just paste the same shutter speed in the Motion Blur tab
and the same F-stop in the Thinlens tab. Simple as that
Or you can even plug these parameters into Xpresso to automate this.

[pxlntwrk]

Ok, ok I didn't understand how to use it
It f***ng does the trick.
thanks again

[lanklaf]

Ok, ok I didn't understand how to use it
It does the trick.
thanks again

<3

[whersmy]

lanklaf! Is there a version as .orbx for us Standalone users to try it out?