LED and Lumen Setting

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HoppyHopp
Posts: 35
Joined: Thu Aug 27, 2020 6:27 pm

LED and Lumen Setting

Post by HoppyHopp »

Hey,
i try to build a LED-Channel. I know that the opal cover transmit about 55-60% of the light and the LED-Stripe has 300 lumen/meter.
But in the render looks more like a sun.
Did i something wrong?
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B.Y.O.B.
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Re: LED and Lumen Setting

Post by B.Y.O.B. »

Did you use reasonable tonemapper settings?
HoppyHopp
Posts: 35
Joined: Thu Aug 27, 2020 6:27 pm

Re: LED and Lumen Setting

Post by HoppyHopp »

Did you use reasonable tonemapper settings?
I use always the default settings.
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HoppyHopp
Posts: 35
Joined: Thu Aug 27, 2020 6:27 pm

Re: LED and Lumen Setting

Post by HoppyHopp »

Is there any difference between Gain and Exposure in World->HDRI settings?
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B.Y.O.B.
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Re: LED and Lumen Setting

Post by B.Y.O.B. »

If you use real-world light units, you will also need to use real-world tonemapping units.
For a start, you could take a photo of a light source with similar brightness. Then check the ISO, F-Stop and shutter time chosen by the camera, switch the tonemapper to "camera settings", and enter similar values.

About gain and exposure:
final_gain = gain * (2^exposure)

So gain is a linear factor, while exposure is an exponential factor.
HoppyHopp
Posts: 35
Joined: Thu Aug 27, 2020 6:27 pm

Re: LED and Lumen Setting

Post by HoppyHopp »

Thank you, so is this workflow right?

1. default settings
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2. matching LED with tonemapping
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3. matching HDRI with exposure setting to match the default setting brightness
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4. result in a room looks right?
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CodeHD
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Re: LED and Lumen Setting

Post by CodeHD »

We had a thread before on this kind of topic:

viewtopic.php?f=4&t=1938&p=24448#p20979

perhaps you find some helpful info there?
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