Skydome/Environment clouds to work with Iray Sun/Sky lighting
Connatic
Posts: 279
I like the results of the Sun/Sky lighting environment setting in Iray. I know that the Sun will continue to shine light if Dome and Scene is used with no map assigned to the sphere. What would be great is a product which allows easily-applied cloud textures which work with the Sun. If the background of the cloud textures were transparent it should work wonderfully. There is probably a way to use two layers with the various domes.
Daz 3D is part of 
Connect
DAZ Productions, Inc.
224 S 200 W, Suite #250
Salt Lake City, UT 84101
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2024 Daz Productions Inc. All Rights Reserved.
Comments
Yes please, they don't need to be rigged clouds, just a set of domes that work with the native Iray sun/sky.
How about a blank sky dome with multiple sky settings that have ZERO effect on light ?
Light passes through it like it is not there, so it does not FUBAR the lighting in your
scene BUT..because of that, the sky itself must be self lit...or it would render black.
so basically a really smart skydome.
A sky dome that does the following
1. multiple sky backdrops
2. Sizable- and choose to stretch sky picture or not stretch
3. Totally transperant to exterior lighting...no effect on scene lighting
4. sky illumination level adjustable...only effects sky...does not effect scene
5. can add custom skys
6 can add and move sun independant of sky
7 can add moons or planets or rings...independantly illuminated
ya, that would be perfect
The Sun/Sky will still show the radiant sky behind the overlays of clouds/open sky mix. Even the clouds can be partially transparent. I made some crude versions, erasing the open sky and leaving the clouds on some existing maps and it worked fine. It works like the real sky with sun and blue sky behind whatever clouds are present. The difficult part of making this is placing some believable clouds on a transparent background or making a good transmap.
It's not hard to make clouds that add a veil of varied transparency. The tricky part is that clouds in the sky have directional lighting, because (of course) they are big blobs with all sorts of interactions with light.
THAT'S hard.
The idea is to make the sky portion of an hdri map transparent. The cloud portions should still contribute their light. There is probably an amazing way to get this accomplished. The right combination of maps controlling opacity and scattering should work in a similar manner to actual clouds partially obstructing the sun and radiant sky.
Some very good ideas happening here, some I'm already working on- very close to this.
All of this is within my skillset, the individual items, but kinda hurts my head to think about all of them playing nice with each other. I'll crunch on it a bit.
Threads merged as they are very similar topics.
...apologies fr waking this from the dead, however this is one of my biggest concerns with Iray.
The Iray Sun/Sky setting is the most accurate for outdoor daylight scenes. Traditional skydomes do not work, and HDRIs require their own "sun" asd well as need to be of high enough resolution (minimum 8K horizontally) so as not to look out of focus. Personally I prefer to build settings up by using meshes for the "ground" as shadows will more accurately follow the contours than on a flat shadowcatcher plane.
While photo backdrops or billbaord clouds are an option, the issue with these is the lighting and shadows are fixed (or in teh case of billboards, "baked in"). The backdrop feature in Daz has the lmitation in that it is locked to the rendering camera. If you rotate the camera the backdrop rotates with it, One workaround is to use a large plane primitive with a photo atached as a texture, but this too has issues in that it is flat, not curved, and there is the risk of shadows from mesh elements in the scene being cast on it.
The bottom line is, It would be nice if we could create our own sky textrues as can be done in Bryce, Carrara, and Vue for Iray. All three of those programmes also support volumetric clouds which have substance as well. Now I am aware that Iray (at least the version in Daz) is somewhat deficient in this department and a number of workarounds have been created (I made one myself) but these tend to be for fog, smoke, and dust effects rather than actual clouds.
A couple weeks ago there was an Iray Toon Cloud product (which uses actual meshes for the clouds) was released, but they are not meant for more realistic scenes. It would be nice to see something similar in the realistic sense however given the various cloud types that occur in nature such a porduct would most likely be daunting to create and use as well as possibly resoruce intensive.
I've used this with Sun-Sky lightting. It's not as sophisticated as some of the ideas above but it does work quite well.
https://www.daz3d.com/iray-clouds
Cheers,
Alex.
..yeah that is part of what I mentioned. Billboards usually have lighting and shadows "baked in" that require matching the sun angle just like with a photo backdrop which is why I didn't purchase it.
I would also like skies with cirrus, cirrocumulus, altocumulus, and fair weather cumulus, as well as mixed/layered cloud types like below:
those Iray clouds dont have any lighting baked in,they are just billboards and obviously not as good as volumetric clkouds..but they will interact with your lighting
I was just struggling with this issue today. So frustrating to want to use an HDR for a background and the Sun Sky at the same time for the best lighting. Ended up doing it in postwork.
This would address my single greatest frustation.
They are extremely dark when used with HDRI, even using the lightest setting.