This question has always been asked a lot on our Blog + Social Media accounts (and basically everywhere on the internet): Is Environment Background better than Dome Light? Or is it the opposit?
Well, it varies from designer to designer. But for me, Environment Background has always been better. I never really liked Dome Light (unless I’m rendering a scene where I’ll put in a Background later, via Photoshop).
This tutorial is all about how I use Environment Background in my renders to simulate different times of day in a scene.
For the VRay 2.x tutorial, go here.
Important Note: If you’re going to be rendering a scene like the one in this tutorial, I highly advise using an HDRI with a rsolution of 16K or more! You can also use a Panorama image with a similar resolution (but don’t map it as Spherical, map it as Screen or Cylinder).
Noon Environment Background
You can find it here.
My favorite time of day to render!
To set up a scene for noon (or mid-day lighting in general), you need to start with your Sketchup. In the Shadows window, turn on your shadows to see a preview in your scene and set the Time slider to anywhere between 11 am and 1 pm. You can also play around with the Date slider to adjust the sun’s angle.
Once you’re satisfied, you can turn off the shadows and fire up your VRay Asset Editor.
Go to the Lights tab, and from there open the Sunlight settings.
All these settings may look a bit too overwhelming, but I’ll explain this step by step.
- First, you need to Enable Sunlight, and make sure it’s Invisible.
- Turbidity: This setting will depend on what type of HDRI you’re using, whether it’s Beach, Desert, Jungle, City, etc. (so the sunlight matches the atmosphere). Basically the higher the number in Turbidity the ‘dustier’ the sunlight will be (Dusy Orange), and the Lower the number the more ‘pure’ the light will be (Perfect Yellowish Light). Click here for a clearer preview.
- Ozone: This setting, just like Turbidity, depends on your chosen HDRI. The Lower the value, the more Yellow your sunlight will be. And the Higher the value, the more Greyish Blue. Click here for a clearer preview.
- Intensity Multiplier: Controls how strong your sulight is. You can balance that with your Camera Exposure settings.
- Size Multiplier: Since your sun is invisible, we will use this as a way to either sharpen the shadows cast by the sunlight or blur them. Small Sun = Sharp Shadows, and vice versa. Click here for a clearer preview.
We’ll leave the rest of the settings for a later, more advanced tutorial. For now, these settings are more than enough. You can test render to preview your settings.
While test rendering your settings, you need to set an appropriate Camera Exposure value; it’ll depend on your machine + the windows’ sizes + the lighting in your scene. I set mine at 9.
Now let’s see about adding that Background!
Go to Settings in your Asset Editor, and enable EVERYTHING under your Environment dropdown.
Now, click on the Texture Icon to add your HDRI (or Panorama). Add the file as a Bitmap. Then, set your UVW as UVWGenEnvironment and Mapping Type as Sphrical (Screen or Cylinder if you’re using a Panorama).
It’s best if you do this step while Interactive Render is on; you can test render the image with the HDRI and rotate it to your liking. You also need to pay attention to the sun direction in your HDRI so it matches your scene. To rotate your HDRI image, scroll to the Direction Transformation and set your Horizonatal Rotation to your liking (anywhere between 10 and 350 Degrees). I set mine to 180 Degrees to have a Sea View. The Vertical Rotation tilts your Image Forward or Backward, you’ll need that in very rare cases.
Once you’ve set your Environment Background to your liking, Copy your settings to all the others by simply right clicking on your Texture Icon. Set the value of the Background while test rendering, then add lower values to the others so the textured lighting doesn’t overpower your scene. Example is below.
When rendering your final image (or while you’re test rendering for it), take advantage of your Frame Buffer’s built-in editor; it’s a very powerful tool that will help you achieve the best image possible.
I only use the Exposure settings because I like to edit everything else in Photoshop (personal preference); I can dim or brighten the image via Exposure, adjust my Contrast to compensate if the image looks too washed out. My favorite thing ever about this tool is the Highlight Burn slider! I almost always move it down to 0 to elminate any ‘over bright’ or ‘burned’ areas in my image. It also gives the lighting a very realistic effect when it’s at a low value.
Important note: When saving your final render, save both a PNG format and a JPG format; your PNG image will have a transparent background, so we’ll add in the background later via Photoshop by layering the two. Reason why to go through this hassle is because in Post Production, you may want to edit the Foreground and Background differently. If you don’t want to do this you can uncheck the option Alpha Channel in VFB Channels.
Dusk / Dawn Environment Background (Sunset/Sunrise)
For a Sunset or Sunrise scene, the steps are similar to a Noon EnvBg but with two exceptions; the values will change, of course. And we’ll have to add interior lighting. For a Tutorial on adding and tweaking Interior Lighting, go here.
First. we’ll adjust the Sketchup Shadows to mimic the time of day. My image has a Sunrise HDRI, so I set it as such. I deliberately avoided any Sun showing up in my scene, when tweaking the shadows; my HDRI orientation dictated so.
Next, we’ll adjust our VRay Sunlight settings. During Dusk or Dawn, sunlight isn’t pure yellow, it’s more of a pinkish orange hue mixed in with a blue-violet (watch a real life sunset/sunrise to know what I mean). Sunlight will also be weaker, and a bit hazy. The settings below reflect that.
Next, we’ll add an HDRI to the EnvBg (short for Environmet Background; it’s too long hehe), and adjust that.
Don’t forget to copy your settings, paste them on all the below, and adjust your values for each.
Next, test render and add your interior lighting. Afterwards, you may adjust the image Exposure in the Frame Buffer.
P.s.: I’m still using a Camera Exposure value of 9. I always do.
Night/Overcast Sky Environment Background
The reason why I said that I don’t recommend taking a straight shot of my HDRIs at the beginning of this post is evident here.
For a Night/Overcast Sky shot, we won’t be adjusting the Shadow slider in Sketchup (because there is no sun). So make sure your Sunlight in VRay is Disabled.
We’ll go straight to the EnvBg and add our HDRI, and adjust it if needed.
Next, we’ll copy and paste the settings to all the others, add interior lighting, and start rendering.
Extra Tip (Backlighting)
A little nifty trick that works like a charm every single time! Add a Rectangle Light behind your camera to help light up your scene properly (works really well in a Daytime render where you want to rely only on ‘Natural Light’).
Next, add the same Image used as your EnvBg as the Rectangle Light’s Texture if you’re rendering either Noon, Dusk, or Dawn. But, use it as a regular light source if you’re rendering Night or it won’t make a difference.
Make sure to check Invisible and uncheck Affect Reflections or it’ll show up in your scene. If it’s affecting your scene’s shadows in an unrealistic or unpreferable way, uncheck Shadows.
For a tutorial on Post Production, please let us know 🙂
Hope this tutorial has helped you out and asnwered all of your questions regarding Environmnet Background. For any further questions or suggestions, please leave a comment below! You can also contact us via Facebook & Instagram.
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