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Exteriors I still find difficult. Especially realistic shadows...


Roodogg
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For weeks, I have been playing around with various render settings in vray. gamma 2.2 / 1.8 / 1. different colour mapping types.

 

 

In the end I have found there is no substitute for 2.2, although I find I don't get any nicely defined shadows, especially under the eaves of my building. If I look at photographs / other studios work, I see very dark areas in nooks and crannies and that is what eludes me with my exteriors. Using Vray Sun / Sky Either areas are dark-(ish) or in direct sunlight with no gradient between the two.

 

 

I don't particularily wish to use HDRI yet as I would like to master V-ray's inbuilt system before I do. Though I feel it doesn't give me realistic results at the moment.

 

 

If anyone could give me pointers on how they set up exteriors, especially for the type of architecture I show here, I would be in their debt.

h1.jpg

Edited by Roodogg
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I don't know what you have tried and what you are using here, but the few things that I would recommend with a Vray Sun/Sky setup are:

 

-Increase the Size Multiplier of the sun. Try 5-10. This will soften the edges of shadows.

-Reduce the intensity of the sun. It is just too bright by default. I would try in the 0.85 range.

-I also kill the Turbidity and Ozone as much as possible. I think 2.0 and 0 are as low as they will go. This will just clean up the haze and make the sky color more blue. You can add what you want back in post.

-Be sure you are using AO. A Dirt pass or tick on AO in the GI Roll-out. Keep it smal. 2-10 inches.

-Lastly, I have been using Reinhard lately. It just looks better in my opinion. I use a Brightness Multiplier in the 0.3.

 

After this, it's all about the curves/contrast in post.

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Cheers for the swift reply Corey.

 

 

I am using a vray sun and sky with pretty much default settings

 

 

I'm shying away from AO. I reckon AO should come from my lighting setup if possible as it's a 'fake' effect really, isn't it?

 

 

I'm more talking about what you see in the attached photograph. There is a very obvious gradient running from the eaves down to where the sunlight becomes unobscured. This does not seem to be possible with vray sun sky, especially using LWF. It is better with gamma set to 1 although means entirely dark areas not facing the sun.

 

 

I hear what you're saying about curves and I do post process my images, but in order to accentuate attributes in an image with curves, they have to be somewhat there in the first place, no?

example.jpg

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To add to all the great tips Corey gave you..

 

Check your environment intensity, it seems like you could stand to drop the environment light a little bit.

 

I tend to not use any tone mapping in my vray camera, rather than set it to daylight I set it to neutral and do the overall hues in post.

 

Also check what material you have on the ground under your building. If you have a pretty bright surface, ie the white rock, it will bounce an unnatural amount of light back up into your eaves. If this does this, you can use just a darkish gray material at the GI Override.

 

Those great contrasty renders you see probably all look like your render out of Vray. 99% of what you see is done in post where you have so much more control and ease of editing. Don't worry too much about getting a perfect out-of-the-box rendering as you'll waste a ton of time in doing so. Get a render that is close, then do the rest in post.

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Yes, white rock will be bright and bounce light in the real world but not in any way that Vray calculates it. To add to that, in the real world the white rock isn't a plane with an image mapped to it. It's a ton of small objects with cracks and cervices to trap light and multitudes of facets to bounce light in every different direction.

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Hi Peter,

 

one thing that people omit in recreating real-life conditions is the environment. They model, and it seems to be your case as well, only the very next surrounding of the building. Because of that, the moment your site ends, VraySky model will shine outside from ground what is impeccably more intensive that true bounced light. You can get around this by using VrayPlane (infinite) with darker gray tone to using full spherical HDRi (one that is fully spherical in texture, i.e. not black lower half).

 

The next thing is horizon, now you have empty horizon so most of the light goes from there, simply mapping something there, like cylindrical enviro with alpha channel of surrounding houses or trees or anything will contribute to more realistic light behaviour in your scene.

 

There are 100s other small things but, but this is starter :- ).

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Hi Juraj and thanks a lot.

 

 

I do actually have a large invisible plane just under the landscape to stop light coming from underneath as you have mentioned. Having some more objects to stop horizontal light would help also.

 

 

Having read everyone's suggestions and played around with my settings, I realised I need to be more aware of the GI my materials create and also, obviously, my lighting. I will re-post the image later on.

 

 

Again, thanks.

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For this scene, gamma 2.2 is oveerkill, it is already bright, just my 2cents.

Post some settings, for camera, sun and color maping.

Gamma 1.0-1.6 would be much better.

...

You work in linear or Reinhard?

Try Reinhard with burn value like 0.3-0.5, even 0.8-1.0, I do not know your enviroment settings.

...

You have pretty nice scene, to make it awesome.

The colours are washed out too much, due to gamma 2.2 and thats main problem.

Also, use, maybe some darker sky?

This one is too bright, for Europe or USA, this is more like Africa or tropicals.

Good luck!

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Gamma doesn't wash out images, improper albedos and light setup does, people are just used to setting stuff wrong so when they set one thing right the other ones won't match. Not fault of linear workflow.

 

Contrast adjustment can be done in post(PS/etc..) or directly in framebuffer by levels/curves or even contrast/HSV/etc..(if you have Vray3). But NOT by setting wrong gamma. It's not artistic aproach, it's wrong approach.

 

 

The "gradient" Peter tries to achieve is only possible in linear space anyway, any other gamma would render the proportion between light and shadow completely incorrectly. There is no problem with VraySun/Sky or linear.

 

Oldie but goodie:

 

The Visual Difference Between Linear and Non Linear Workflow

 

This stuff shouldn't be discussed or questioned in 2014. It was horrible 4 years ago, but now ? If you start 3dsMax 2014+ and Vray 2.4+, it is already set correctly by default.

Edited by RyderSK
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Ah the old gamma argument again. Never tire of this one! ;) I'm sticking with 2.2 as with 1, everything is too severe. Contrast, colour burning etc

 

 

Here are my settings as requested and a new rendering taking into account suggestions on this thread.

 

 

To address the lighting issues I had, I've actually gone back to an HDRI for lighting. 2 dome lights, one set to gamma 1 for skylight and reflections and one set to .5 for sunlight. Seems to work ok. Now I need to work on balancing my hues - something Juraj has mentioned on many posts I have read.

settings.jpg

h1.jpg

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Really interesting what Zdravko said actually about the image not looking like it's in the UK (It's London) -

 

 

I did a google search by image with it and it came up with lots of photos of buildings in Arabic countries. That's interesting to say the least!

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2 dome lights, one set to gamma 1 for skylight and reflections and one set to .5 for sunlight.

 

Beware of such radical difference, 0.5 will not only boost contrast, but even the overal brightness of the HDRi so much (like multiples of exposure steps) that your reflection one will be vastly behind, contributing to "dead" tamed reflections.

 

I am personally not fond of this double domelight approach. The benefit is flexibility, not better "realness". If you want better lighting from your HDRi, boost the overal intensity of sun in some app like HDRStudio or manually in Photoshop to still keep realistic ambient light and reflection.

 

High quality HDRIs (like CGSource) would be at 0.9 already like Supernova in contrast, while the ones needing much bigger contrast aren't really that good (for sharp, direct light, they're ok for everything else though).

 

You didn't need to abandon VraySky/Sun so quickly though, this type of architecture and the overal site, don't benefit from HDRi much at all.

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I am not LWF expert at all, but it seems you've applied gamma 2.2 , 2x times?

...

1st in MAX settings, and 2nd in VR general settings rollout?

 

No he didn't, it's correct. (although makes little sense to keep Reinhard in this sort of setup, because it's still forced linear, this is what happens when you listen to everybody...)

 

He has ticked "don't affect colors" (depreccated setting, should update Vray to 2.4.04), so the result is still linear that only evaluates sampling based on 2.2, helps with bright and very dark tones, which would have stuck-in noise.

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The previous setup was using reinhard, I just didn't change it back to linear multiply when I ticked 'don't affect colours' as Juraj explained, it doesn't make a difference. I find anything towards exponential (including Reinhard) does weird things to the colours.

 

 

Juraj, when you speak about aligning hues in materials / textures, what is a good methodology? Is there any writing on this?

 

 

I have purchased many hard books on digital texturing and lighting but nothing really ever taught me anything I didn'r already know.

Edited by Roodogg
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It's continual learning for me as well. I do slight calibrating in Photoshop based on my own photos, but it's good deal of eye-balling references as well, knowing the conditions behind.

 

But check that other thread posted here yesterday, seems like a great info there.

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  • 2 weeks later...

Spent a lot of time playing around with settings and materials with no progress on photorealism... In the meantime, I have produced an interior I'm really happy with.

 

 

There's something extremely fundamental I am missing with the way I produce exteriors!

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Peter, I think the lighting in your first post and your last post both look good, I think you may be overthinking things...

I'd also suggest that you disable the area filter in the AA settings, just render with no filter, you can always soften in post if needs be.

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Spent a lot of time playing around with settings and materials with no progress on photorealism... In the meantime, I have produced an interior I'm really happy with.

 

 

There's something extremely fundamental I am missing with the way I produce exteriors!

 

They are a just a little bit more overbrighted, and maybe desaturated, nothing more. And white ground material is not so attractive...

Also, choosing right sky, is 50% of good exterior. Try to pick some sky with not so much clouds.

CHECK VIZ PEOPLE, they have some free skies!

Look on these images, they are maybe oversaturated, but not too much, for making comparasion, as they are very similar to your enviroment.

 

http://trideval.blogspot.com/2013/07/yard-house-with-pll-north-europe.html

http://trideval.blogspot.com/2013/07/kids-playground-north-europe.html

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They are a just a little bit more overbrighted, and maybe desaturated, nothing more. And white ground material is not so attractive...

Also, choosing right sky, is 50% of good exterior. Try to pick some sky with not so much clouds.

CHECK VIZ PEOPLE, they have some free skies!

Look on these images, they are maybe oversaturated, but not too much, for making comparasion, as they are very similar to your enviroment.

 

http://trideval.blogspot.com/2013/07/yard-house-with-pll-north-europe.html

http://trideval.blogspot.com/2013/07/kids-playground-north-europe.html

 

I think those are pretty bad lighting references and would be a step backward for Peter.

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Oh, apologies. I meant bad reference, not bad imagery. As in not in the right direction relative to the OP. The images are indeed saturated and contrasty, more towards stylized, not in the LWF vein Peter seems to be going for. Peter is also siting his work in London, the grayest place on the planet.

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