Any better ways to use a single HDRI sphericals map both as env and lightning?

[I3ordo]

Just to clarify,
I'm looking into whether there have been any improvements in using an HDRI as both the background and lighting source—without needing to create a separate exposure-adjusted instance for the visibility override.

Ideally, I'd like to use a single HDRI map that I can tweak and control for both the environment lighting and the background. But when I try to do that, I run into this issue:

In the past, I’ve relied on LightMix and multiple environment setups to manage this, but I’m wondering if there’s now a more efficient or streamlined method.

I'm actually fine with how the environment looks—I just want both the environment and the mesh to be lit consistently using the same map.

Right now, the workaround I use is to create a second instance of the HDRI: one for direct visibility (the background), and one for environment lighting. I boost the background version by +2 and reduce the environment version to -5.5 to get this result:


But I really wish there were a better solution for this in 2025.

[Aram Avetisyan]

Hi,

This really depends on many things.
You can simply use one bitmap, plugged to different output/color correction nodes and plugged to environment and/or overrides.
I have found this to be the most functional way.

[I3ordo]

So this is a common issue?

I always assumed the HDRIs I was using were incorrectly tone-mapped or something, and I ended up constantly fiddling with them because I didn’t really understand what was going wrong.

Now I just want to make sure none of my settings are causing the problem.

I really admire the Corona materials and overall rendering quality—it always feels like everything that comes from the Corona team is well-calibrated and physically accurate. So I decided to test this using an HDRI directly from Chaos Cosmos: **"HDR map 723"**.

Here's a screenshot of the HDRI I used:
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And these are the settings I used in the environment slot:


I don’t think the scene should be coming out like this. I can clearly see shadows being cast from the sun position in the HDRI, so the directionality looks correct. But with all settings at default, is it really supposed to look like this—so bright?

It would be wonderful if someone could say, "Hey, you're doing this part wrong. Change this setting, and it’ll fix the discrepancy between the lighting and the visible background." That’s exactly the kind of clarity I’m looking for.

[TomG]

Unfortunately, there is no standard for the way HDRIs are set up, so you'll find some work for background and lighting without needing separate adjustments, and some won't. Loading the HDRI once and then just passing it direct into one place, and through a color correct in the other, is the easiest solution, and will always be required in some situations due to this variance in how HDRIs are created and set up :)

[I3ordo]

Unfortunately, there is no standard for the way HDRIs are set up, so you'll find some work for background and lighting without needing separate adjustments, and some won't. Loading the HDRI once and then just passing it direct into one place, and through a color correct in the other, is the easiest solution, and will always be required in some situations due to this variance in how HDRIs are created and set up :)

Thank you so much for the explanation—now I can tweak the settings with peace of mind.

[maru]

This particular HDRI doesn't seem to be calibrated correctly. If you place a Corona Sun next to the sun in the HDRI and check their RGB values, you will see that the Corona Sun is about 2x stronger than the one in the HDRI. I don't think there was some cloud layer or haze in the air while capturing that HDRI, it looks clear. The sunlight intensity on the 3D objects appears much lower than for example on the church facade in the image. Note that this HDRI is provided by a 3rd party vendor.

[I3ordo]

This particular HDRI doesn't seem to be calibrated correctly. If you place a Corona Sun next to the sun in the HDRI and check their RGB values, you will see that the Corona Sun is about 2x stronger than the one in the HDRI. I don't think there was some cloud layer or haze in the air while capturing that HDRI, it looks clear. The sunlight intensity on the 3D objects appears much lower than for example on the church facade in the image. Note that this HDRI is provided by a 3rd party vendor.

Well , measuring the pixel values a great tip!
i first had to match the hdri's sun angle
using corona slect map, alternating with corona's sky map
i lined up them up so that the shadow cast by the corona sun   is almost the same as the hdri's...
vs

i created a CShading_RawComponent just to measure the brightness value
measured the ratio between light and shadow for the corona's sun which was 10:1 so the tip of the vertical box was ~50 and the shadow cast by that box was ~5,

so i changed the curve of the hdri to match that ratio of 10:1
so got this... monkey brain style



i think i can get away with this method for a while.