I've been doing quite a bit of experimenting and testing to come up with a method for creating volumetric atmosphere ("fog") that reacts with light, shadow, and caustics. The example renders below are:
1. Green glass scene with volumetric caustics, lit with an IES spotlight + HDRI environment.
2. Interior scene with volumetric godrays, lit with an HDRI environment.
3. Lake scene with volumetric murky water depth, lit with an HDRI environment.
4. Stone island scene with volumetric mist, lit with an HDRI environment.
For the caustics scene, the fog was rendered directly in the beauty shot; for the others, the fog was rendered in a separate pass, and composited in Photoshop with a combination of Lighten and Screen blend modes.
The basic technique is this:
1. Create a primitive cube which encompasses the scene, then split into 6 separate faces with the Geometry Editor.
2. Create a "Fog XYZ" material: Advanced type, Diffuse = 50% grey, Specular = 0, Refraction Index = 1, Diffuse Transmission = 50% grey. Connect a Color To Number node to the Opacity channel, which controls the fog opacity via the Output From value (.1 in the caustics example scene).
3. Apply a Transformation Animation node to each of the 6 faces, along their respective normal axes, moving a distance equal to the scale of the cube (either positive or negative, depending on the initial position of the face). For example, in the caustics scene, the cube has a scale of 80, so each face has a translation value of either +80 or -80 in X, Y, or Z.
4. Set the FPS in the Timeline to 1, and the duration of each of the 6 translations to 1 second.
5. Enable Motion Blur.
Once Motion Blur is enabled, you will see the volumetric atmosphere begin to build up in "slices". The longer it renders, the smoother the fog will become. It will react with light, shadow, and caustics. For the murky water and mist fog passes, only the Y plane was utilized, starting from the bottom of the lake bed and the water surface, respectively, and a Color Fade animation node was applied to the Opacity of the Fog XYZ material to fade the fog as it moves up. The mist has a Fractal (Noise) node applied to the Diffuse and Diffuse Transmission channels, with Number Fade animation nodes applied to the Scale and Falloff, to break it up a bit. Also, for the murky water scene, the Fog XYZ material has a greenish color applied to the Diffuse and Diffuse Transmission channels. For the interior, lake, and stone island scenes below, I've attached the final comp, as well as the beauty and fog passes. I'm also attaching a link to a KSP tutorial file, which includes the setup used for the green glass caustics scene. It contains the volumetric fog cube with animations, the backdrop ramp, the spotlight, and 3 spheres with Gem, Diffuse, and Flat Black materials. There are 3 Scene Sets: Beauty, Caustics, and Fog Pass. The Fog Pass has a Flat Black material applied to all geometry except for the fog planes. When rendering the Caustics scene set, Caustics and Interior Mode should be enabled under the Lighting Tab.
Link to KSP file: http://bit.ly/2gQRNf7
Interior scene from cgtrader.com
3D rock scan by MGD Films, from sketchfab.com
Cheers,
Eric
Great studies Eric. You are pushing Keyshot to the limit ! That green glass scene looks fantastic.
Quote from: NM-92 on December 04, 2016, 11:38:15 AM
Great studies Eric. You are pushing Keyshot to the limit ! That green glass scene looks fantastic.
Thanks very much, Nico! I really appreciate the kind words :)
Cheers,
Eric
This is way, way cool - those volume caustics are f****** awesome.
I'm in admiration of you :)
God rays and murky water are seriously outstanding efforts. All of them are smashing!
Martin
Very amazing Eric!
Quote from: Despot on December 04, 2016, 01:20:05 PM
This is way, way cool - those volume caustics are f****** awesome.
I'm in admiration of you :)
Thank you so much, John! To receive a comment like this from one of the most admired artists ever in the history of keyShot is, well...f****** awesome :)
Quote from: TpwUK on December 04, 2016, 01:29:38 PM
God rays and murky water are seriously outstanding efforts. All of them are smashing!
Martin
Thank you very kindly, Martin! I appreciate your kind words :)
Quote from: LayC42 on December 04, 2016, 01:44:54 PM
Very amazing Eric!
Thanks very much, Marco! Very kind of you to say so :)
Thanks again, guys...
Cheers,
Eric
I'm throwing myself with John's comment. This is fantastic! Very creative usage. Loving the mood you got in these images. This will be studied further!
Great job Eric!
Quote from: Magnus Skogsfjord on December 04, 2016, 02:17:22 PM
I'm throwing myself with John's comment. This is fantastic! Very creative usage. Loving the mood you got in these images. This will be studied further!
Great job Eric!
Thank you so much, Magnus! I really appreciate your observations and comments. Please do study it further...would love to see you incorporate the technique into one of your amazing renders!
Cheers,
Eric
Quote from: bdesign on December 04, 2016, 02:25:56 PM
Quote from: Magnus Skogsfjord on December 04, 2016, 02:17:22 PM
I'm throwing myself with John's comment. This is fantastic! Very creative usage. Loving the mood you got in these images. This will be studied further!
Thank you so much, Magnus! I really appreciate your observations and comments. Please do study it further...would love to see you incorporate the technique into one of your amazing renders!
You are too kind, Eric! But yes, the mood you manage to get with this lighting is fantastic. I feel the urge to test it out as soon as possible.
Quote from: Magnus Skogsfjord on December 04, 2016, 02:32:34 PM
You are too kind, Eric! But yes, the mood you manage to get with this lighting is fantastic. I feel the urge to test it out as soon as possible.
Thanks again, Magnus! Too kind?...not at all my friend...you're a brilliant artist :) I'm really happy that you feel inspired by this! Look forward to seeing what you come up with!
Cheers,
Eric
This is absolutely ingenious Eric. Going to put together a write up on this for the blog :)
Mind. Blown.
It is so awesome to see existing KeyShot features being utilized with such creativity! Really great stuff. Thank you for sharing!
Quote from: Josh Mings on December 05, 2016, 08:19:30 AM
This is absolutely ingenious Eric. Going to put together a write up on this for the blog :)
Wow...thank you very much, Josh! That is really awesome! 8)
Quote from: Rex on December 05, 2016, 09:38:47 AM
Mind. Blown.
It is so awesome to see existing KeyShot features being utilized with such creativity! Really great stuff. Thank you for sharing!
Thanks so much, Rex! Your comments really mean a lot :)
Cheers,
Eric
Holy moly! These results are really impressive. #mousedrop
Quote from: Will Gibbons on December 05, 2016, 11:31:16 AM
Holy moly! These results are really impressive. #mousedrop
Thank you, Will! I really appreciate the kind words! (Do I owe you a new mouse? ;D)
Cheers,
Eric
Quote from: bdesign on December 05, 2016, 11:35:11 AM
Quote from: Will Gibbons on December 05, 2016, 11:31:16 AM
Holy moly! These results are really impressive. #mousedrop
Thank you, Will! I really appreciate the kind words! (Do I owe you a new mouse? ;D)
Cheers,
Eric
Nah, I'm covered! lol.
Hi Eric,
man, I can't say how Impressed I am when I saw this thread!
this is super nice!
thanks to you I can use volumetric mist in my upcoming projects!
Thanks again for sharing this dude!
cheers
Quote from: Will Gibbons on December 12, 2016, 08:07:03 AM
Quote from: bdesign on December 05, 2016, 11:35:11 AM
Quote from: Will Gibbons on December 05, 2016, 11:31:16 AM
Holy moly! These results are really impressive. #mousedrop
Thank you, Will! I really appreciate the kind words! (Do I owe you a new mouse? ;D)
Cheers,
Eric
Nah, I'm covered! lol.
cool ;)
Quote from: Hossein Alfideh on December 13, 2016, 09:49:19 AM
Hi Eric,
man, I can't say how Impressed I am when I saw this thread!
this is super nice!
thanks to you I can use volumetric mist in my upcoming projects!
Thanks again for sharing this dude!
cheers
Hey Hossein-
Thanks very much, man! I actually thought of you and your "Into the Wild" series when I posted this ;) Look forward to seeing what you come up with!
Cheers,
Eric
Quote from: bdesign on December 13, 2016, 10:30:23 AM
Quote from: Hossein Alfideh on December 13, 2016, 09:49:19 AM
Hi Eric,
man, I can't say how Impressed I am when I saw this thread!
this is super nice!
thanks to you I can use volumetric mist in my upcoming projects!
Thanks again for sharing this dude!
cheers
Hey Hossein-
Thanks very much, man! I actually thought of you and your "Into the Wild" series when I posted this ;) Look forward to seeing what you come up with!
Cheers,
Eric
Thanks man! :)
can't wait to try it myself!
Wow, Eric, you already know, I am a huge fan, but this! This is just incredible, I don't know how you come up with it, but I am glad you do and are kind enough to share with the rest of us. Thanks again
Quote from: dmerziii on December 13, 2016, 01:04:39 PM
Wow, Eric, you already know, I am a huge fan, but this! This is just incredible, I don't know how you come up with it, but I am glad you do and are kind enough to share with the rest of us. Thanks again
Thanks very much for your incredibly kind and humbling comment, David! You're quite welcome...happy to share :) Good to hear from you, man.
Cheers,
Eric
Wow, I kinda see how it works, but I'm baffled how you managede to come up with this method in the first place?
I'm surprised that the results looks so good!
Hey Eric, i tried this method on my latest scene (the arcade machine). I have a doubt. Where should i position the animation cursor ? Should i pause the animation at 1 second ? more? less? I see that shifting these values the results are different, but i don't know the correct way to do it. I love your test images btw.
Quote from: Esben Oxholm on January 19, 2017, 05:48:00 AM
Wow, I kinda see how it works, but I'm baffled how you managede to come up with this method in the first place?
I'm surprised that the results looks so good!
Hey Esben-
Thanks. I'm not sure what you mean by "I kinda see how it works"(?) Did you try it out and not get the desired effect? If you have any questions, let me know.
Cheers,
Eric
Quote from: NM-92 on January 19, 2017, 10:22:10 AM
Hey Eric, i tried this method on my latest scene (the arcade machine). I have a doubt. Where should i position the animation cursor ? Should i pause the animation at 1 second ? more? less? I see that shifting these values the results are different, but i don't know the correct way to do it. I love your test images btw.
Hey Nico-
Leave the animation cursor in the timeline at the start. You don't even need to hit the play button, just enable motion blur, and the fog will start to build up in "slices" in the realtime viewport. Make sure that the duration of each fog plane animation is 1 second, and that FPS is set to 1. When you try to type "1" in the FPS box, KeyShot will probably default it to "12", so you'll need to highlight the "2" with your mouse cursor and hit backspace to get a value of "1" in the box. When rendering with the animation dialouge window, just make sure motion blur is enabled in the timeline, and render as a still image. Use max samples with a high value to ensure the fog becomes smooth. Did you download the KSP tutorial file I provided? Let me know if you have more questions.
Cheers,
Eric
Oh no ! I totally missed that link. I'm taking a look at the file right now, sorry. Everything understood, thanks for the explanation, it was very clear. I don't think my PC can handle the fog in the arcade scene though. Your file is taking a while to build the mist and it's a simple sphere.
Quote from: NM-92 on January 19, 2017, 06:56:28 PM
Oh no ! I totally missed that link. I'm taking a look at the file right now, sorry. Everything understood, thanks for the explanation, it was very clear. I don't think my PC can handle the fog in the arcade scene though. Your file is taking a while to build the mist and it's a simple sphere.
Except for the caustics scene, I rendered the volume fog in a separate pass and composited in Photoshop with a combination of lighten and screen blend modes. Much faster to render the fog separately. In the tutorial KSP, you'll see a scene set titled "fog pass". All geometry except for the fog planes has a flat black material applied, like the Godrays fog pass example render in my original post. A separate fog pass also gives you a lot of flexibility in the overall look of the fog when compositing. When I saw your arcade image, I actually thought it would be a cool scene to try the volumetrics. Let me know how it comes along and if you have more questions.
Cheers,
Eric
Oh i see. The separate fog pass is a nice idea. I'll check all this out. Thanks for the patience Eric.
Quote from: bdesign on January 19, 2017, 04:37:05 PM
Quote from: Esben Oxholm on January 19, 2017, 05:48:00 AM
Wow, I kinda see how it works, but I'm baffled how you managede to come up with this method in the first place?
I'm surprised that the results looks so good!
Hey Esben-
Thanks. I'm not sure what you mean by "I kinda see how it works"(?) Did you try it out and not get the desired effect? If you have any questions, let me know.
Cheers,
Eric
I just tried to express that even though I understand why this methods works, I'm impressed that you were able to come up with the solution! :)
Quote
I just tried to express that even though I understand why this methods works, I'm impressed that you were able to come up with the solution! :)
+1 to that. Level: Professor.
Quote from: Esben Oxholm on January 19, 2017, 11:50:53 PM
Quote from: bdesign on January 19, 2017, 04:37:05 PM
Quote from: Esben Oxholm on January 19, 2017, 05:48:00 AM
Wow, I kinda see how it works, but I'm baffled how you managede to come up with this method in the first place?
I'm surprised that the results looks so good!
Hey Esben-
Thanks. I'm not sure what you mean by "I kinda see how it works"(?) Did you try it out and not get the desired effect? If you have any questions, let me know.
Cheers,
Eric
I just tried to express that even though I understand why this methods works, I'm impressed that you were able to come up with the solution! :)
Thank you, Esben!
Quote from: Magnus Skogsfjord on January 20, 2017, 12:51:18 AM
Quote
I just tried to express that even though I understand why this methods works, I'm impressed that you were able to come up with the solution! :)
+1 to that. Level: Professor.
Oh man, you are way too kind, Magnus! Thank you!
Cheers guys,
Eric
I can't even begin to think through the inventiveness, flair and persistence that these images represent, Eric.
Next you'll be telling me you can model a Spectre of Brocken...
https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB (https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB)
Actually moving the animation cursor can lead to some cool effects also. This one was set on 0.5s right where the planes of the cube meet, creating more dense fog. Image attached.
Quote from: NormanHadley on January 20, 2017, 05:22:19 AM
I can't even begin to think through the inventiveness, flair and persistence that these images represent, Eric.
Next you'll be telling me you can model a Spectre of Brocken...
https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB (https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB)
Maybe it could be tested by making the IoR value that of water/fog?... or faked with a rainbow color gradient procedural set to spherical or cylindrical mapping... who knows?
Quote from: Will Gibbons on January 20, 2017, 06:56:07 AM
Quote from: NormanHadley on January 20, 2017, 05:22:19 AM
I can't even begin to think through the inventiveness, flair and persistence that these images represent, Eric.
Next you'll be telling me you can model a Spectre of Brocken...
https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB (https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB)
Maybe it could be tested by making the IoR value that of water/fog?... or faked with a rainbow color gradient procedural set to spherical or cylindrical mapping... who knows?
Applying a texture to one of the planes can give interesting results too, and it can simulate a rainbow.
Quote from: NormanHadley on January 20, 2017, 05:22:19 AM
I can't even begin to think through the inventiveness, flair and persistence that these images represent, Eric.
Next you'll be telling me you can model a Spectre of Brocken...
https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB (https://www.google.co.uk/search?q=spectre+of+broken&safe=active&espv=2&biw=1087&bih=581&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5r7zK59DRAhWlDsAKHeXUAvsQ_AUIBigB)
What a wonderful compliment, Norman...thank you! I'll see what I can work up for the spectre :)
Cheers,
Eric
Quote from: NM-92 on January 20, 2017, 05:33:09 AM
Actually moving the animation cursor can lead to some cool effects also. This one was set on 0.5s right where the planes of the cube meet, creating more dense fog. Image attached.
Hey Nico-
You can control the fog density with the Output From value of the Color To Number node which is plugged into the opacity channel of the Fog XYZ material.
Cheers,
Eric
Quote from: Will Gibbons on January 20, 2017, 06:56:07 AM
Maybe it could be tested by making the IoR value that of water/fog?... or faked with a rainbow color gradient procedural set to spherical or cylindrical mapping... who knows?
Quote from: NM-92 on January 20, 2017, 08:13:28 AM
Applying a texture to one of the planes can give interesting results too, and it can simulate a rainbow.
Some cool effects can definitely be acheived by applying texture maps, changing IOR, and even changing material types. A glass material can give a trippy "hologram" type of effect as it reflects the environment. Keep on experimenting!
Cheers,
Eric
Eric,
This is absolutely crazy technic you found ! I love what I have seen and I am really happy to use that for upcoming renderings :)
Thanks a lot for sharing this technic ! You are god ! :)
Ben
// Attached my trial with your technic, just made some curve adjustment on photoshop //
+1 with post : adding several times the same renders (with alpha transparency check), it lighten up the scene !
Bravo!
Quote from: BenG075 on January 28, 2017, 05:26:47 AM
Eric,
This is absolutely crazy technic you found ! I love what I have seen and I am really happy to use that for upcoming renderings :)
Thanks a lot for sharing this technic ! You are god ! :)
Ben
// Attached my trial with your technic, just made some curve adjustment on photoshop //
+1 with post : adding several times the same renders (with alpha transparency check), it lighten up the scene !
Thanks very much for your kind words, Ben :) It's nice to see examples of the technique being utilized. I would offer the suggestion that you let the render rez up longer with more samples to further smooth out the motion blur (viewed full resolution, you can see some gaps between the fog planes). Also, rendering the fog in a separate pass is much faster, and allows a lot of flexibility in the overall look of the atmosphere when compositing it over your beauty render (try using a combination of Lighten and Screen blend modes in Photoshop). To render the fog as a separate pass, just create a Scene Set with a flat black material applied to all geometry except the fog planes.
Cheers,
Eric