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kolby
09-12-2016, 04:00 AM
Hi guys, I am doing a exterior visualization of big apartment building. I want to use Sunsky plugin but I am little bit confused how to set it properly. E.g. The scene is created in sRGB color space but Sunsky has it's own gamma settings. I do not know what to set here. Also, there is conversion system which is totally alien for me. Can anyone help me or share some basic settings as a start point to get nice naturally looking summer lighting ?
Thanks in advance.

prometheus
09-12-2016, 05:08 PM
usally I do not use srgb when doing outdoor scenery, it generally flattens out dark shadows too much where you do not want that, if you go for srgb anyway, you may mostly need to correct gamma afterwards.

Just try various color conversions, I tend to use hosec wilkie model with default settings, ranging from color system cie for a more punch blue green sky, cie rec 709 for a similar sky but less saturated...a little more blue, adobe rgb 98 for a bit even less greener more blue than cie rec 709, rec 709 display for a very deep blue sky, adobe 709 for a little less saturated blue sky.
Invert exposure will cut down the exposure if you have higher values, you may wanīt the default 15000 here, but if you use srgb you may also wanīt to adjust that one.

for the rest..keep at default if possible, sky editing turbidity, if you have a value of 1-3 is probably good for clear skies, lower value means less particle that pollutes the sky, a value of 5-8 means smog and such effect, though it doesnīhave a true volumetric fog system built in.

we have been discussing some of it on some threads here, donīt have the time to look for them right now though..



https://www.youtube.com/watch?v=-6PDjQdPyus&index=4&list=PLdaQ-nxd0g2dAB9HoRi9prVqaUh0b_w63

prometheus
09-12-2016, 05:11 PM
and some more...


https://www.youtube.com/watch?v=LxmCg6dPHGc&index=6&list=PLdaQ-nxd0g2dAB9HoRi9prVqaUh0b_w63

prometheus
09-12-2016, 05:14 PM
And another one..thereīs even one more with some sk sun stuff..but I canīt stand the error limits this forum provides with posting not more than one vid.--



https://www.youtube.com/watch?v=I4hTm0xjpis&index=5&list=PLdaQ-nxd0g2dAB9HoRi9prVqaUh0b_w63

zapper1998
09-13-2016, 04:10 AM
any way you could share the scene file????

Please

tk
Mike

prometheus
09-13-2016, 10:44 PM
any way you could share the scene file????

Please

tk
Mike


Not really..not keen on sharing that, sorry.

zapper1998
09-16-2016, 04:24 PM
What I was asking was just the scene minus the landscape object..or objects..

Mike

prometheus
09-16-2016, 07:49 PM
What I was asking was just the scene minus the landscape object..or objects..

Mike
That would just be almost an empty scene without hypervoxel. .

Not sure what you would want that for...Besides ...I currently don't have a good track on where it is.

kolby
09-22-2016, 08:51 AM
usally I do not use srgb when doing outdoor scenery, it generally flattens out dark shadows too much where you do not want that, if you go for srgb anyway, you may mostly need to correct gamma afterwards.

Just try various color conversions, I tend to use hosec wilkie model with default settings, ranging from color system cie for a more punch blue green sky, cie rec 709 for a similar sky but less saturated...a little more blue, adobe rgb 98 for a bit even less greener more blue than cie rec 709, rec 709 display for a very deep blue sky, adobe 709 for a little less saturated blue sky.
Invert exposure will cut down the exposure if you have higher values, you may wanīt the default 15000 here, but if you use srgb you may also wanīt to adjust that one.

for the rest..keep at default if possible, sky editing turbidity, if you have a value of 1-3 is probably good for clear skies, lower value means less particle that pollutes the sky, a value of 5-8 means smog and such effect, though it doesnīhave a true volumetric fog system built in.

we have been discussing some of it on some threads here, donīt have the time to look for them right now though..

Hi Michael, thanks for overview. But I thought it purely technically.
I thought if scene is sRGB, Sunsky gamma must be around 2.2 to be correct with the scene, or 1 if scene is in linear to correspond with luminance and colors of lights, GI, etc. About conversion system, I thought I need select proper system to get accurate colors and luminance on different output devices. (old TV, lcd panels, projectors ... ) I am wrong ?

gerardstrada
10-01-2016, 04:56 PM
A part of getting physically plausible results is to work in linear light. In your terms, scene must be linear, which means you need to linearize input colors. If your images and picked colors are in sRGB standard, an easy way to set this up is to select the sRGB quick preset in CS panel. Sunsky works internally in linear fashion and colors are calculated spectrally first and then converted to a color system. If you are working in sRGB standard (not ideal but most of people work in this way) the Rec.709 Display color system is the way to go for previewing more correct colors.

Tonemapping should be done at the last stages, so it's better to not use any kind of tonemapping when setting Sunsky. A simple way is to use Sunsky in node environment (Textured Environment=>Procedural=>NodeEditor) with DP Linear Tonemap for correctly expose the DP Sunsky calculation and get realistic contrast ratios. Later you can tonemap in post with DP NIF.

This is the difference between using InverseExposed and DP Linear Tonemap:

http://s10.postimage.org/49subfsmx/Sun.gif

There's more info about this stuff in this thread:

http://forums.newtek.com/showthread.php?71751-Extra-Buffer-nodes&p=1267894&viewfull=1#post1267894



Gerardo

prometheus
10-01-2016, 05:17 PM
A part of getting physically plausible results is to work in linear light. In your terms, scene must be linear, which means you need to linearize input colors. If your images and picked colors are in sRGB standard, an easy way to set this up is to select the sRGB quick preset in CS panel. Sunsky works internally in linear fashion and colors are calculated spectrally first and then converted to a color system. If you are working in sRGB standard (not ideal but most of people work in this way) the Rec.709 Display color system is the way to go for previewing more correct colors.

Tonemapping should be done at the last stages, so it's better to not use any kind of tonemapping when setting Sunsky. A simple way is to use Sunsky in node environment (Textured Environment=>Procedural=>NodeEditor) with DP Linear Tonemap for correctly expose the DP Sunsky calculation and get realistic contrast ratios. Later you can tonemap in post with DP NIF.

This is the difference between using InverseExposed and DP Linear Tonemap:

http://s10.postimage.org/49subfsmx/Sun.gif

There's more info about this stuff in this thread:

http://forums.newtek.com/showthread.php?71751-Extra-Buffer-nodes&p=1267894&viewfull=1#post1267894



Gerardo


Thanks for your extensive insigh and thanks for the link, have to check later.

In color space settings (not dp sunsky setting) I mostly just go to presets and have it set to disabled in vpr and rendering, I just canīt stand working with any of those srgb color space presets..I wanīt dark shadows and not washed out colors, if I need to boost lighting up, I deal with lighting and radiosity instead.

You mentioned the Rec.709 Display color system, do you refere to the main lightwave preferences for the color space, or do you mean the dp sunsky color conversion?

Thanks
Michael

gerardstrada
10-01-2016, 07:55 PM
In color space settings (not dp sunsky setting) I mostly just go to presets and have it set to disabled in vpr and rendering, I just canīt stand working with any of those srgb color space presets..I wanīt dark shadows and not washed out colors, if I need to boost lighting up, I deal with lighting and radiosity instead.

I get your point. It's not necessary to disable sRGB display correction though, or preview all in scene-linear. You can just switch to more contrasted display or add output/display adjustments into a 3DLUT, or use DP NIF (which is pre-viewable in VPR though this old card-filter trick (http://forums.newtek.com/showthread.php?136662-LightWave-and-Wide-Gamut-monitors&p=1337325&viewfull=1#post1337325)). We can even have complex output simulations in this way.


You mentioned the Rec.709 Display color system, do you refere to the main lightwave preferences for the color space, or do you mean the dp sunsky color conversion?

Sorry for not being clear. I'm referring to DP Sunsky.



Gerardo

kolby
10-02-2016, 01:43 AM
A simple way is to use Sunsky in node environment (Textured Environment=>Procedural=>NodeEditor) with DP Linear Tonemap for correctly expose the DP Sunsky calculation ...

Hi Gerardo, this is what I do not understand. Can you explain how to setup Sunsky in node environment ? Or better, post any scene with basic setup ? Thanks very much.

prometheus
10-02-2016, 04:04 AM
Hi Gerardo, this is what I do not understand. Can you explain how to setup Sunsky in node environment ? Or better, post any scene with basic setup ? Thanks very much.

AS far as I know, there is no sunsky node to acess in node editor, I think he means adding a textured environment, click on texture, add a procedural texture, from the type of textures you can choose node editor, click on that and enter nodes, from there you have dp filter, if you have installed dp kit that is, and under dp filter is linear tone map, how that is to work with sunsky..I havenīt tested.

kolby
10-02-2016, 06:11 AM
Yup, I do not understand how that work with Sunsky. Simple scene to explore would be very welcome.

prometheus
10-02-2016, 06:31 AM
Yup, I do not understand how that work with Sunsky. Simple scene to explore would be very welcome.

I could set something up..not today, dog tired..
some wise guy complained about me not sharing a sky setup..thinking I am the most selfish dude here on the forums without Even having a sense and obviously not a real clue of what I actually have provided as free stuff here over the years, and all the help and descriptions, But the voxel work which is sort of a special signum that I do not want to share..and takes a lot of work, I have shared how to work with hypervoxels..but the actual work and voxel partīs I am mor inclined to keep for my work.

But basics I could set up, might help zapper out too...though I really think itīs quite easy to set up..thatīs why I may have sounded a bit purky with comments above that I donīt understand why you guys would want an empty scene with just the sky setup.

Iīll t try tomorrow if nothing getīs in the way, however..the node setup Gerardo spoke of, that I have not much clue on, I tried a bit..but I had crashes in lw 2015 while testing the dp nodes, and I am not keen on trying again.

zapper1998
10-02-2016, 07:05 AM
coolness thanks
just getting use to Octane and its power, and all the tips and help is most appreciated.

Received the GTX-1080 Gigabyte card and put it in below the Titans, wow fast the 1080 is dang runs circles around the Titans, wow impressed.. money well spent after a few weeks of doing some researching the reviews on the 1080. I have the Gigabyte MB so the Gigabyte GTX-1080 no issues, no coil whine, well haven't gamed yet, been a little busy doing this warehouse project.

Thanks again
Mike


"Zapper", was my call sign in the Navy, "1998" is the year of my Harley Davidson Softail.

kolby
10-02-2016, 08:10 AM
... why you guys would want an empty scene with just the sky setup.

I just want to see what is connected and where. Nodes aren't my cup of tea. :confused:

djwaterman
10-02-2016, 09:25 AM
I've been using the Sunsky plugin lately for architecture renders. It's pretty simple, don't worry about the color profiles in the actual plugin, I don't. Basically, create a light that will be your sun, change it into a Sunsky sun in the light settings. Check the manual control so that you can rotate it yourself rather than inputting day, month and time data. Next go to the Background options and choose the Sunsky environment, in it's settings you assign the scene light to be the sun, you can play with the other setting too, mainly you might want to play with the sun diameter and brightness, this is mainly for it to show up in reflections or in the actual background sky. Choose which ever sky-type you think will work, there are two choices and you'll see you can also play with turbidity and sky color, but just leave that stuff at default to get started.
Once back in the scene you can rotate the sun around and see the sky color and light color change as the sun goes low or high, it's really simple and takes but a few clicks to set up once you've done it once. And of course work in LW's sRGB color space. In the end it only has to look correct so it's up to what you think is the correct look, For stark daylight I usually set my light at 120 intensity, and with that Sunsky light you adjust the angle settings to give you overcast soft shadows or sharp defined shadows.

Matt also has a tutorial on his Pixism website, he uses something called the SunSpot Motion Modifier, I can't remember if that is a different thing, but just use my method first since its quick and then look at his video to see if it is better or different.

http://www.pixsim.co.uk/

prometheus
10-03-2016, 01:52 AM
I've been using the Sunsky plugin lately for architecture renders. It's pretty simple, don't worry about the color profiles in the actual plugin, I don't. Basically, create a light that will be your sun, change it into a Sunsky sun in the light settings. Check the manual control so that you can rotate it yourself rather than inputting day, month and time data. Next go to the Background options and choose the Sunsky environment, in it's settings you assign the scene light to be the sun, you can play with the other setting too, mainly you might want to play with the sun diameter and brightness, this is mainly for it to show up in reflections or in the actual background sky. Choose which ever sky-type you think will work, there are two choices and you'll see you can also play with turbidity and sky color, but just leave that stuff at default to get started.
Once back in the scene you can rotate the sun around and see the sky color and light color change as the sun goes low or high, it's really simple and takes but a few clicks to set up once you've done it once. And of course work in LW's sRGB color space. In the end it only has to look correct so it's up to what you think is the correct look, For stark daylight I usually set my light at 120 intensity, and with that Sunsky light you adjust the angle settings to give you overcast soft shadows or sharp defined shadows.

Matt also has a tutorial on his Pixism website, he uses something called the SunSpot Motion Modifier, I can't remember if that is a different thing, but just use my method first since its quick and then look at his video to see if it is better or different.

http://www.pixsim.co.uk/

Pretty simple suggestions, and yes..easy to follow.
About light, yes..once double click to open sunsky, you select desired light..which can be anything, by defualt it is set to none.
If you have a simple default scene..all you can choose from is light..which is the default light, to change it to sk_sunlight, you have to enter the lights property and change it from there to the sk_sunlight, and as you said, set it to manual for easier control, Unless you need a specific location and time for your sun, then you may consider using the position, time zone option instead of manual, but then you can not mover or rotate the sun with native controllers.
You do not need the sunspot modifier, you have almost the same settings in the time zon tabs, zone for location, and time for day,month, year, and a time decimal, sunspot modifier has exact clock variables..not sure what may be the best here, I really donīt use them.

If you wanīt a lensflare to follow with star point flare, you would have to add the sk_sun modifier (not sunspot modifier)..and perhaps increase distance settings, this will match the lensflare to the sk_sundisc a bit better..which otherwise is completly off.

Note..sunsky also has a script..(add sunsky) it may be faster to use this, if you add it to a special menu, like background or effects and place it somewhere as a button for backgrounds or backdrop, you would have a one click button to set this up, rather than going to environment, then drop down, add sunsky environment, select light, change lights etc..with the add sunsky script, this is all set up for you..with the addition of another light called sk_sky light..a sort of fill light.
By default the script set the sk sunlight up as time zone..but you can ofcourse just change that instead.
The add sunsky script is located at the bottom of the page...
http://dpont.pagesperso-orange.fr/plugins/Sunsky.html


About sunspot modifier,

gerardstrada
10-03-2016, 11:48 AM
Quote Originally Posted by kolby View Post
Hi Gerardo, this is what I do not understand. Can you explain how to setup Sunsky in node environment ? Or better, post any scene with basic setup ? Thanks very much.

AS far as I know, there is no sunsky node to acess in node editor, I think he means adding a textured environment, click on texture, add a procedural texture, from the type of textures you can choose node editor, click on that and enter nodes, from there you have dp filter, if you have installed dp kit that is, and under dp filter is linear tone map, how that is to work with sunsky..I havenīt tested.

There are several ways to control Sunsky exposure with DP Linear Tonemap. That's a way. Another way is using DP NIF, other way is using a camera filter card. A simpler way could be probably using the Layer opacity Envelope with Textured Channel => Procedural ) => Node Editor in a Sunsky layer in TexturedEnvironment to control the exposure of the whole Sunsky Layer. The same Textured Channel could be copied in SKSunLight intensity as well.

https://s15.postimg.org/sru2rswop/lin_TMsetup.png

The reason to use DP LinearTonemap instead of the common setup by default is in cases where one need to get correct sun reflection intensities together with diffuse values. Because Inv. Exp. Exposure parameter normalizes the sun intensity by scaling it to 100%, so more realistic contrast ratios are not possible in this way if no 3D light is used.

Using LinearTonemap of course implies that the whole lighting (sun and sky) will rely on Sunsky environment only - no light for sun is necessary for outdoors with Importance Sampling. If lighting rig is including an actual light, you might skipt Linear ToneMap setup, because in such case, the sunlight component is solved separately from the skylight component.

The reasons to worry about color systems in DP Sunsky is just if one need realistic color consistency and predictability (instead of eyeballing all the time for each single project). Common setup by default uses CIE Rec.709 which is D65 illuminant. All sRGB computer monitors are D65 -BUT- all OSs use D50 adapted profiles, so values by default in ALL Sunsky tools are only correct if image is directly sent to a Rec.709 video monitor standard. People who use a computer monitor for previewing, need to chromatically adapt these values to D50. This is what the Display versions of color systems in DP Sunsky do.

http://s29.postimg.org/yulqw8hzr/dpsunsky.gif



Gerardo

pinkmouse
10-03-2016, 02:14 PM
Every time you post something Gerardo, I learn a little bit more, but also appreciate the depths of my ignorance to a greater extent...

:D

gerardstrada
10-03-2016, 03:44 PM
Sorry for that...

:D



Gerardo

kolby
10-04-2016, 09:30 AM
Thanks Gerardo ! Everyday is something new to learn.

gerardstrada
10-05-2016, 08:59 AM
Hope it helps, Kolby! :thumbsup:

Another aspect you might want to take into account to set this up more correctly when using linear workflow is to leave the Light Color parameter in CS panel as Linear, because Sunsky colors are linear, as the data got by SK Lights. If by chance you are using other lights in scene, you'll have an inconsistency there, because those other light colors you need to pick by hand are gamma corrected and they do need to be linearized. This is one of the reasons why I think ALL picked colors should be gamma corrected in the picker instead of globally. A way to do this is with SG_CCPicker (http://www2.informatik.hu-berlin.de/~goetsch/CCTools/). The correct setup for a sRGB display is to correct from 2.2 screen gamma to linear output (not from sRGB as many people wrongly assume).

https://s17.postimg.org/tmkzhcdlb/sgccpicker.png

The Custom Images slots there are in case you want to use screenshots of your favorite color-wheels.



Gerardo

kolby
10-05-2016, 09:51 AM
Yes, of course it helps. Thanks Gerardo !