Are there settings for the Sky Atmosphere and SunSky for a nice ambient blue-ish night sky?

https://forums.unrealengine.com/unreal-engine/feedback-for-epic/1683537-new-sky-atmosphere-model-in-4-24?p=1755912#post1755912

That post makes it sound like its possible and I believe thats what theyre using in Fortnite now too, right?
I have messed around with just about every setting on the sky atmosphere, the light and exposure but i still cant get anything but a black night sky. (need it to work real-time, not baked, and with time of day change)

So far i can get around that with the old method of adding another skydome, hdri or whatever additional stuff i want, but it would be nice to not have to.

Some posts also mentioned not having to use the height fog any more, as well? That the fog in the sky atmosphere could do all the same up close fog effects (light rays and volumetric cones from nearby spot lights) but no luck there either. Increasing the mie scattering, like some suggested, just darkens everything.

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You have to create two directional lights, and set one of it (the one that will become the Moon) to “Atmosphere Sun Light Index” to 1… or any other number, bigger than zero, as the Index number Zero is usually the sun, or the first directional light. After giving each a different index number, you can control those two lights with this thingie (the second one will crtl + + shift + l +mouse movement), or just set them manually.
Then you alter the second one to a bluegreyish color, intensity to about 0.26 lux (or whatever is good for a dark night, but the docs say this number) and raise the source angle (4 looks quite good for a full moon, especially if you use the Convolution Bloom).

The low Lux number for the Moon is the part, where you need to play with the exposure to prevent a black scene, unless auto exposure does it´s job and adjust it for you.

And maybe this helps you:

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@Suthriel I’m actually interested in that as well, but I can’t get a good result from what you wrote.
When the hour is late (after 20:00 on my time) it’s dark pitch.

When I add a 2nd directional light, set the index to 1, and the lux to 0.26 - the scene is completely visible, as if it’s afternoon or something like that.

Ive had some decent luck with the second “moon” light and low exposure values. I was hoping to do it without needing 2 directional lights, but this is working out pretty well.

Thanks for the response!

Yeah, umm, go into the post process and change the min exposure setting to something like 0.2 or 0.3, then it should become darker during the moon phase.

Also, don´t forget to recapture the skylight, you can do it during runtime too. New levels have blueprints for this in it by default.

A quick test:

Wow, youtube messed up the video quality of the dark time pretty bad ^.^

Actually using the Sun & Sky actor this seems to be in it by default, so one shouldn’t do anything when using it.
And thanks for the video too ^^

That actually made things darker, thtanks!
I don’t seem to have the actual moon circle at night at sky like you do though. how do you do that?
I do have the sun showing up during the day show ( as a cirle at night, that is )

p.s.
I also notced you’re using 10 lux for your sun light. I used the default value which is a physically based value:

just saying incase it matters / why I don’t actually see the moon it self?

Well, it was another default scene from a brand new created 4.25.3 standard project with a new level, as you can see at the not present yellow arrow for resetting this light intensity to it´s original value :slight_smile: So who knows, how many default scenes they have with different values for the same scenario, causing different results for everyone ^.^ I only had reduced the Directional light for the Moon :slight_smile:

The initial value is 100000 Lux, which is the physically based brightness value. It doesn’t have to be set that bright to get a brightly lit scene. Simply change the value to 100 or lower, then adjust Auto Exposure to compensate until lighting is not overbright or too dark. Increasing Min of Exposure is going to get a reverse effect of the lighting, and decreasing gets a reverse…same for the Max Exposure value. But Max is going to get a more drastic effect if Compensation is in the positive, if I remember correctly. Compensation is basically a scalar parameter that increases / decreases brightness level of light by a sort of multiple (actual math is more complex though). So, to get a moon brightness on the scene (not the moon’s appearance of how bright it is in the sky, but the brightness it’s causing on the ground), reduce the Compensation value so it results in Min/Max adjusting being less intense or quick. Try using a negative Compensation value, then set Min to super low (-10 or -20) and Max to 5 or 10. See what happens. Try different values to see how it affects the scene brightness.

To render a moon in the sky, add a new (2nd) directional light, then I think you’ll need to set the Sky Atmosphere Channel to 1 (sun is in channel 0 for day), and modify that new directional’s properties with the look of a moon. In the video above, those settings are shown when it turns from day to night (as a reference). The moon was exceptionally bright-looking in the sky, so change the Sun Disc Illuminance to a lower value.

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