Night shot

[borisquezadaa]

I havent seen any night shots in the gallery so i converted one industrial scene i have using the scripts in the forum from Vray.

Pretty much out of the box settings on corona, one hdri in environmental slot and a couple of mesh emitters on the lamps.
19 hours so far.
The hdri shows as some small brigth dots on the back. Some kind of bug?. I lower the hdri to 0.01 (from 1 as default) to mimic night illumination from sky.

Any suggestions would be very appreciated.

[Ludvik Koutny]

That's quite strange. I hope you do not use large geometry sphere around scene instead of environment map. Btw 19 hours for such a simple rendering is rather extreme. Even 19 minutes would be too much for this kind of scene ;)

[borisquezadaa]

You were right... deleted the sky dome mesh and put the hdri in the environment slot. Much better, however not quite there yet.

I'm gonna try the sun model from corona. Also replace the mesh emitters  for sphere lights.
It is possible for sun model from corona can mimic night? (If i put an adecuate angle greater than 90 degree?). Could be a good addition.

[Ludvik Koutny]

You can use CoronaSun with Max's daylight system. There you should have all the control you need. And 4 hours is still too much. Check 3ds Max asset tracker if you have bitmap paging enabled. It should be always disabled.

[borisquezadaa]

The same using dayligth system from max whit coronsun, no skyligth.
I set the sun time by 23:00 pm and i get this kind of sunset mood.

Guys in the forum told me that i could turn corona sky in to a moon with litle effort... lets see what can i came up to.

[Ludvik Koutny]

You should set sun to use solid color, otherwise it will tint based on angle. It is also quite remarkable how slow renders you are able to achieve. 38 minutes on so fast machine and yet so extremely grainy. I do not think i would be able to achieve so slow render even if i tied my best to.

[romullus]

If you're not going for dusk, but for night, then you don't need any map in enviroment at all. Just solid pure black color. Starlight is so extremely dim, that it's not worth to calculate. You can put any map you like, in visibility override, though.
As for moon, you can use corona sky or daylight system, it doesn't matter really. But in case you choose latter, don't forget to change mrsun to corona sun and turn off mrsky completely. And lastly, dial down intensity of sun (moon) significantly, like hundreds or even thousands times.
Now, all is that left, is to add artificial lighting.

[borisquezadaa]

All rigth... start from scratch.

The moon ligth isnt blueish as i tough  has a temprature of 4100-4150 a rather yelowish tone. And thanks to this http://en.wikipedia.org/wiki/Purkinje_effect we perceive as blueish. So i put the Corona sun as 4150 Kelvin Temp.

Respect to relative brightness to dayligth, using this info http://en.wikipedia.org/wiki/Daylight i use 1/1000 as Intensity on the sun.

I-m lost respect the size of the moon respect of the size of Corona Sky but as i intend to apply photoshop on the disc i leave as 5 for now.

I never knew that where a setting like bitmap paging in max and by default where active. If you wish to wait for your renders forever leave this on. See this as reference http://jokermartini.com/2013/11/14/render-speed-increase/.Thanks to suggest that.

Using a default Corona material override, in post settings in corona use 4150 as white balance as the predominant ligth source was the moon. Giving me a yelowish tone. But just as stated before our eyes shift that illumination to blue so i try a value of 3150 to return to that blueish color.

For the lamps i put corona sphere 3000 Kelvin  for simulating tungsten ligth. This link explains a little about moonligth photography http://www.cast-lighting.com/search/1/display-document/71

I try an spherical star map as suggested in the forum but it turns out that the stars renders too big and unnatural.
This is the link for that realistic position and brigthness star field http://paulbourke.net/miscellaneous/starfield/

Resume>
IMAGE 4150ML-4150WB   4150 kelvin sun, 4150K White balance in postprocessing tab
IMAGE 4150ML-3150WB   4150 kelvin sun, 3150K White balance in postprocessing tab to mimic blueish tint from human eye
IMAGE 4150ML-3150WB/3000TL   4150 kelvin sun, 3150K White balance in postprocessing tab, corona ligth 3000 K Tungsten ligth , corona ligth sphere
IMAGE STARFIELD just a render whit spherical star map from http://paulbourke.net/miscellaneous/starfield/

Thats it for now...

[Ludvik Koutny]

See? Now these are acceptable rendertimes :)

[borisquezadaa]

A little update adding the moon in post. I'm quite pleased with the results.
Starting to like Corona a lot.

[Ludvik Koutny]

I could not resist to try a little postprocess work, because i think this really has a potential :)

[borisquezadaa]

Pretty awesome indeed!... could you share some tips on the post processing?. The force is weak with me in post. XD.

[Ludvik Koutny]

It's really just a bunch of glows, glares, slight color adjustments and vignette :)

[maru]

post competition ;)

[nehale]

and so it continues