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elecman
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Were you able to reproduce this?
ChrisHekman
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elecman wrote:See the attached image. The black spots are caused by the spotlights called "instrument flood light".

Some other questions:
-The render is pretty low dynamic range. How do I reduce the intensity of the areas where the sun hits the cockpit? Hightlight compression is already set at 1.
-Why is the overall image so blue?
The attachment cockpit.jpg is no longer available
The scene we have here does not have instrument flood light. Could you send me an updated version?
Did you override them? What are you settings?

"The render is pretty low dynamic range. How do I reduce the intensity of the areas where the sun hits the cockpit? Hightlight compression is already set at 1."
I would like to make a note on this topic, also in light of the other thread.
Under the hood octane is fully hdr (32 bit float RGBA (128bit per pixel). This means that a color channel can range somewhere between 0 and 3.402823 × 10^38 theoretically.
The issue here isnt the range. The issue is how this range is tonemapped down towards the standard rgba format for your textures/screen.
I have attached a picture that has a clearly visible interior without having a high intensity sun by changing settings in the imager and increasing the sky turbidity a little bit. Is that in the direction you are looking for?

-Why is the overall image so blue?
In the scene I have here, you have two spotlights that are yellow. (Dome light left/right) In unity this yellow light makes the blue textures/materials look a bit more greenish.
These spotlights are blocked by other geometry in octane. So they do not show up in octane.
If you want the greenish effect like in unity, I dvice you to either move the spotlights in the right direction. Or ignore the spotlights altogether and make the panels (Light dome) emit the light you want via emission.
Going the panel route should result in less noise in octane, and faster render time.
Attachments
cockpit.png
elecman
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I have sent you a PM with a new version which has the black spotlight issue.

Thanks for clearing up the HDR issue bit depth issue. I am glad to hear that this part isn't the issue.

When adjusting the settings you suggested, it does look better, but It still looks way better if I export a 32 bit EXR and tone map it in Photoshop. I disabled all lights but the sun to make sure this isn't the issue. In reality the emissive panel text isn't visible at daytime because they are quite dim relative to the bounced light, let alone direct light. to create the correct look, the sun has to be very bright.

I guess what I am looking for (and I am sure I am not the only one) is a more physically correct out of the box solution. It is known how bright the sun is, and it is known what the HDR response of the human eye is. As I understand, Octane is a physically correct renderer, so it shouldn't be too hard to create a default look which looks like the real thing. Perhaps adding a human eye (instead of camera) response curve/tone map setting is a good idea? Also, publishing what value of emissive/light intensity equates to what real world value in lumens would be helpful.
render Octane 4.jpg
Maikel
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As mentioned in this thread, we are working on a new way for users to apply tone mapping in Octane. This will allow for greater, custom control over the final look of an image.

The thing is that different users expect different out-of-the-box behavior. Looking at this from the point of view of a camera sensor, which takes absolute samples, using Gamma = 2.2 / Linear workflow makes sense, as such generated content is likely to go through some color grading / post processing.
Tone mapping comes with a lot of fudge factors, especially when it comes to attempting to emulate an eye (which is much more of a contrast detector, rather than an absolute measuring device) the question is more about "look and feel", what you want the image to say. Which is what post processing is about.
This article talks about what I mean: http://www.creativeshrimp.com/hdr-light ... pping.html

With regard to lights, Octane itself wants to know the luminous efficiency (no light source is 100% efficient) and the power of that light source in Watts. Color is best specified as either black body radiation or as a Gaussian spectrum (wavelength of light).
More information can be found here: https://docs.otoy.com/StandaloneH_STA/S ... ghting.htm
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elecman
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Ok, I understand. Thanks for the article. Interesting read.
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