Need Advice Lighting Characters in Outdoor Settings in Iray
dracorn
Posts: 2,333
On more than one occasion, I create an outdoor background and use an HDRI or in this case, Iray Worlds Skydome. My background looks good in the test renders, and then I add my character, who is too dark. I try all kinds of things to add more light to the character - but it makes the whole render too light and I lose my cool shadows and still the render is grainy and my character is not lit well enough. Dark skin adds an additional challenge.
Finally in frustration, I changed the camera angle and rendered the background by itself, then rendered the character by himself, which allowed me to use LY Leonine Pro HDR Lighting. I composited the two renders in Photoshop and used a warming filter for a minor adjustment on the character to make him blend into the background.
I'm looking for tips on how to best work with troublesome lighting. Thanks!
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Comments
Ghost lights
Iray Worlds Skydome IS dark. Look at ALL the promos using it. It is a particular look that is useful if that's what you want. For bright outdoor renders, I use HDRI's from the UltraHD series; for instance, Sunny Beaches Pack 1. Find a sky with the colouring you like. Load it and your character. Rotate the dome (Render Settings / Environment / Dome Rotation) until you get the look you want. Experiment with increasing the Brightness and Shadows with the one-click Tonemap settings provided in the UltraHD package. If the beach shows in the background, parent everything to a null or to your character, and increase the Y axis setting by 1000 or more until all you see is sky (the higher you go, the brighter your image may get).
In the first image I would try a Primitive Plane along his near side, big enough to hide him and pulled back a few centimetres so there is space between. Go to the Surface Tab, make sure the plane is Iray, and set the Cutout to 0.001, or add a zero until it disappears. Go to the Emission settings and change the colour to white, Temperature to 4500 and lower the Luminence until there is just enough light to lighten the dark side of your figure.
Thanks for your advice, everyone!
Ghost lights was the first thing I tried, scorpio, without much luck. The more I brightened them, they made my background too bright while my figure remained dark.
Interesting to note that Iray Worlds Skydome is dark, xyer0. I tend to be pretty partial to dramatic shadows and was hoping to keep those while lighting the figure. I wanted to try it because it gives more control than your standard HDRI. For example, Skies of iRadience have been tinted, and try as I might, I couldn't change that. I tend to go for plain sky HDRI's because many of the UltraHD has subject matter in their images that I don't want. They can be pretty specific, though I do see where I could use some of them - you've got some pretty good tips there. I typically use Orestes IRay HDRI Skydomes - I like variety in my skies. HDR's are great but don't give the same control over brightness, color, etc. that I had with 3DL skies.
I'll have to try that, Fishtales, it's a good tip.
I'm going to take your advice and do some experimentation before I spend time creating the perfect scenery and become frustrated again.
@dracorn
You could do what a photographer would do and add a spotlight on the character. Change the geometry to Rectangle and dimensions to something like 100 H x 50 w and vary the lumen value to just get the character lighting you want. Focus the light on the character.
FWIW, you can change the brightness of HDRIs. Granted not color for all HDRIs
Turn off Spectral Rendering and that'll help. At least it does on my 7 year old laptop with no nVidia video card. (Only in Scene Only or Dome 6 Scene, with a HDRI or Sun-Sky it seems the lights is equally dim with or without Spectral rendering. I am running some more render tests to be sure & if it's true will be opening a bug report (although since nVidia GPU render and CPU render code paths are different missing precision might be the culprit).
Thank you for the tips. I'll experiment with them.
I agree.
IRL, a photographer will use lighting, reflector cards and fill cards to illuminate an area on the subject when mother nature isn't doing the trick. Doing it in a render is okay, too.
Here are two renders that demonstrate the Spectral Rendering (possible) bug in iRay in DAZ Studio 4.12+ (maybe earlier versions too but I hadn't personally noticed it then). This happens if you use "Dome & Scene" with or without HDRI maps. I'm pretty sure it happens with "Dome only" and "Scene Only" too. It does not happen with "Sun-Sky Only", however, I noticed with "Sun-Sky Only" that the light intensity seem markedly reduced. Reduced light intensity is what happens with "Dome & Scene" when Spectral Rendering is enabled and photometric light sources are in the scene. When Spectral Rendering is off the light intensity increases. Whether the increased light intensities are the correct values or the decreased light intensities are the correct values, I don't know; but it seems to me that the increased light intensity values look correct to my eyes anyway. I CPU render as I have no nVidia video card so that says to me that the code paths that are rendering a nVidia rendered image vs a CPU rendered image are taking at least two different code paths and this )possible) bug says not all those paths have been tested (if this is a bug and not expected behavior for spectral rendering).
You can see from the images rendered that the spectral rendering on seems to almost 100% dim the photometric light sources inside the bakery while the spectral rendering off seems to allow the photometric light sources in the bakery to work correctly. It generally appears to me that the light generated by the dome seems the same whether spectral rendering is on or off.
If I use Sun-Sky only then that dims, possibly completely turns off the light from the photometric light sources in the bakery. If that's the intended code behavior it's certainly counter intuitive (but then the photometric lights in the bakery and elsewhere aren't part of the 'Sun-Sky Only', regardless a hobbyist isn't going to expect Sun-Sky to turn off all photometric lights in a scene. So something implicit about the definition of Spectral Rendering "on" could be why the photometric lights seems to be turned off when it's used (at least when CPU rendering but if nVidia rendering doesn't behave the same it's a bug).
Does anyone know the correct behavior? I will submit a ticket if the behavior isn't correct.
++++
Also I just added Emil HD & Dorothea to the scene and apparently that takes up too much memory (16 GB RAM in my laptop) so I have to dial Emil down to less than HD I guess.
That's intereseting, nonesuch00, and may be the mystery answer to some problems I have noticed.
I've had occassion where my combination of lighting will render spotlights and linear pointlights useless, i.e., I can put them to millions of lumens and with no effect. Only mesh lights work in that case.
In another case, I've used the lights that come with an environment and when I try to add more, it will either oversaturate completely or be completely unresponsive. I've taken to loading the set without the promo lights and just added my own. Sometimes I've been working with a set for successive renders (using Iray Light Probe Kit) and spot/pointlights stop working.
Weird.