Realistic Night Sky

Sparrowhawke3D

There was a total lunar eclipse last night. Almost every time there is an astrological event here we get overcast skies. Comets, eclipses, we always seem to miss out on these rare events. I did get to see the 'blood moon' earlier in the year though. It was more like a rusty moon but quite eerie.

I tried to reproduce this with Carrara's Realistic Sky Atmosphere today but found that it doesn't work well at all for any kind of night sky. Once the Night time setting is turned on the light does not react with the clouds and they turn black. Moonlight should pass through the clouds and when I look out at the full moon tonight it's there glowing behind them.

The best work around I could come up with was to trick Carrara. In the scene I've used both a Sun Light and a Moon Light with the brightness of the sun set to 0%. I also lined up the sun and moon lights to be at exactly the same angle. In the Realistic Sky Editor I set the Sky Color Control to be black. The Sun Size was set to 0% but I used the sun's aura. Any use of atmospheric haze only makes the night sky white so I used black fog to get a fade toward the horizon.

There are some plugins that can create a starfield background but I don't have them so I Googled and downloaded an image with a clear detailed picture of the Milky Way and stars. The necessity immediately arose to be able to change the angle and rotate that background picture, so as quick as my fingers and mouse could tap and click away I invented my own simple plugin code to achieve that. The image brightness needs to be turned down when the moon is fuller for realism. This plugin needs a bit more testing but could prove useful.

I thought I'd share this and to ask if anyone else has tried to render a Realistic Night Sky.

WendyLuvsCatz

I saw the red moon last night and indeed even with a clear sky (Adelaide smog and light pollution notwithstanding) would call it more a mud moon.
yes carrara's moonlight is severely lacking light, your workaround worked well

argus1000

I have played numerous times with the sky editor to render a night sky. It is difficult in Carrara.I have only one moonlight at 50%, and then I set the color of the sky to black. I play with the global brightness. I check the moon and the sun in the editor and also play with the auras. I also put the fog to black. The first pic is the result.

Thanks for sharing your method. It is innovative. I followed it to the letter. I think it might better than my method. The second pic is the result.

Dartanbeck

Very cool set of techniques, Sparrowhawke, Thanks for sharing in such excellent detail!
When I first started into Carrara, I was living in a place where I could pull out my telescope (6" Newtonian Reflector on a tracking German Equatorial mount from Russia) and was a much more avid stargazer/galaxy and nebula hunter at the time. I came to the forums and did extensive Google searches on how to get stars into the background. It seemed that the only advice was to use a background image.
Back then, I didn't know the difference between Backdrop and Background, and was really put out on the fact that the image stayed the same as I slewed the camera about, as I was numb in the head and used Backdrop! LOL
So was born Starry Sky for Carrara. My daughter got the call that they had found the extremely rare kidney that she needed, so we packed our bags and took the long journey to the transplant center. Due to constant complications - almost losing her several times each day, I was forced to find a way to remain the rock. Carrara helped immensely, and over those couple of months, living out of a fairly empty suitcase, I came up with several cool ways to replicate extremely low-polygon-count glowing stars of varying shades onto gigantic invisible globes surrounding the scene. The largest and smallest of these globes simply use a random replication with clustering, while the two medium sized globes use distribution maps: One uses a map that I painted to create earth-bound constellation shapes onto, and then hit shuffle over and over (and over... and over...) until I got the sizes and colors placed the way I liked them to be - and that's the default, saved replication for that one. The second simply uses a more vague map which will easily create more random constellation shapes in the sky.

So with three or all four replicators visible together, I was able to get a stunning realism that truly reminds me of our dark, star-filled skies of NE Wisconsin! I was overjoyed with this, but the new kidney kept winning the game of trying to kill my daughter, so that had to come out. But enough of that... she's safe and just put herself through, and graduated online college... her kidney will come in time!

Anyways, to keep things easy to work with - without having a big mess, all of the star models occupy the same space in the scene, and are then surrounded by a black cube to hide them - directly below dead center of the scene. Many sizes in white, slightly yellow, slightly red, and slightly blue. The largest stars in the two constellation replicators also have an aura applied to them. The lens flare version includes bulb lights on each of those larger stars to give them the flare ability. For my (realistic) tastes, I kept the lens flares and star effects very subtle, but the instruction manual has many details on how to tweak the system.

So using that recipe, Carrara users should feel free to try this sort of technique themselves. SS was my debut product that made me a DAZ 3D published artist, and they let me keep the cost really small - as I mostly just wanted it to be more of a "How-To" product, giving folks like me, who like to tinker, some useful ideas which spawned from months of endless toil. It's also a time-saver for those whom don't have endless hours to tinker in such a manner.

But it's really easy and fun. I hold no secrets and would be happy to assist anyone in setting something like this up - just ask - but the above recipe is the gist of it.

Now, using the sun and/or moon and/or clouds from the RSE can be a little tricky. By accident, my beta tester and I found that the stars look fantastic with RSE skies, which was not at all intended. But we just need to be aware that the stars can end up in front of the sun, moon, and clouds, depending upon the arrangement. My beta tester and I both found it fairly effortless to tweak these situation out by either adjusting SS or the RSE. It's just a matter of being aware of what's going on - these things work much like background/backdrop in that they'll appear behind scene elements, like the stars. So just make sure that no stars are where they shouldn't be and it works out wonderfully!

I was mainly going with sunrise, sunset, and full night skies, and both of us noticed what you've pointed out in your post. It's really cool to see how you've overcome the situation. I love the design of the Carrara RSE, and certainly don't disagree with how they've set it up to have such a situation, rather than the other way around - making it easier for the more common uses... bravo to the wonderful fullness of Carrara features. As I've read through your post, it just makes all too much sense. Using the safeguards of the default situations, and then opposing it with a 0% daytime tweak is just brilliant!

One last thing to this long babble - I have also found that Carrara's fog with various chaos settings along with the 3d glowing stars can make for some spectacular nebulae! I have an unfinished supplement to SS with many deep sky wonders that is planned to be finished in the future. One of them is the Orion Nebula, which looks quite realistic.

Cheers Sparrowhawke and All... Thanks again!

evilproducer

Wait, Dan, you placed the objects that are supposed to be replicated in a cube to hide them? You do know that even if you un-check visibility, they should still show up in the replicator, right?

Dartanbeck

evilproducer said:

Wait, Dan, you placed the objects that are supposed to be replicated in a cube to hide them? You do know that even if you un-check visibility, they should still show up in the replicator, right?

I didn't know that.