Perfecting day time visual renders

[D C]

We've often found that daytime views are the most difficult to produce to a high standard.

 

Dusk/Night. Are generally a lot easier to work with as you have plenty more to play around with. More colours, internal and external lights for example.

 

We have a decent bank of high quality daytime hdris from various sources, and yet it's a struggle to get a render out that stands up to our moodier visuals.

 

I guess what I'm asking is, what can one do to improve the appearance of daytime visual renders? I appreciate the need for post production but I'm leaning more to letting the render engine do most of the work in order to retain the photo realism we require.

 

Thanks.

[Francisco Penaloza]

To get a good or great image, you need good modeling, materials, lighting setup, camera composition and a good project too.

Care or share some image samples to understand what are you looking for?

[Tom Sproule]

Often I'll use two or three HDRIs. We'll set the Sky Dome light to 1.0 on the multiplier and we'll take the HDRI and set the both multipliers to 1.0. Then adjust the camera, so that the lighting and shadows are correct. We won't pay attention to the background or reflections at this stage. This is just to get the lighting correct. We will adjust the Inverse Gamma anywhere from 1.0 to 0.7 to create sharper shadows. With the correct light, if needed we'll make the HDRI invisible in options and set it not to affect reflections/refractions. Then we'll use another HDRI in the reflection/refraction slot of the Environment tab in V-ray. And normally the same HDRI in the background slot of the Environment and effects dialogue (8). If needed we'll use a backplate in the Environment map instead and just make sure it's set to screen instead of spherical environment.

 

Now you might already know all of this. Basically what I'm saying is we use one HDRI for lighting and if needed another for reflections/refractions and possibly a third for the environment sky.

[D C]

We haven't considered using HDRI's for the background placed into the environment slot before. I'm assuming this is to keep the scene and its environment as close to fully rendered as possible? Placing 2d skies in Photoshop can sometimes produce less than ideal results!

 

I've noticed the vast majority of daytime renders are actually late afternoon to early evening shots. More shadows and contrast at that time of day! The problem with this on our end is that we generally deal with large residential tower block schemes. Any daytime plaza/public realm scene is therefore in shadow at these times of day, this means we are looking to use HDRI's that provide as much sunlight into the space as possible, 11AM-4PM but then this doesn't provide contrast as there is less shadow.

[CliveG]

I've noticed the vast majority of daytime renders are actually late afternoon to early evening shots. More shadows and contrast at that time of day! The problem with this on our end is that we generally deal with large residential tower block schemes. Any daytime plaza/public realm scene is therefore in shadow at these times of day.....

 

My inclination would be to be like our journalists and media - "don't let the truth get in the way of a good story". Add some faux lights and increase the reflectivity of the surrounding buildings etc. to bounce more light into those spaces. Be prepared to paint with light if you want your scene to look more dynamic because midday sun is not going to help add depth and character on it's own. But still try and use photographic references if possible, to help your image "lie" more convincingly.

[Francisco Penaloza]

We haven't considered using HDRI's for the background placed into the environment slot before. I'm assuming this is to keep the scene and its environment as close to fully rendered as possible? Placing 2d skies in Photoshop can sometimes produce less than ideal results!

 

I've noticed the vast majority of daytime renders are actually late afternoon to early evening shots. More shadows and contrast at that time of day! The problem with this on our end is that we generally deal with large residential tower block schemes. Any daytime plaza/public realm scene is therefore in shadow at these times of day, this means we are looking to use HDRI's that provide as much sunlight into the space as possible, 11AM-4PM but then this doesn't provide contrast as there is less shadow.

 

There are lots of thing here that can be resolved.

First processing any render in Photoshop will increase the quality output many times. Accent color, change colors, accent shadows, glows, replace skies, people, weather you can do everything in post, you need to practice and know your tool and the final quality will be better.

If it look bad is because you didn't do it right.

 

Regarding HDRI, this it been talked a few times here, and the truth is about 80% of HDRI you find online are not well processed. They are not as High dynamic range as they pretend to be, when using those images is when you get bluish tinted renders, lack of contrast on shadows and other problems. If you use a well prepared HDRI to lit your scene it will have a consistent sun shadows, nice reflections glossiness and everything that Environmental lighting will give you. You can also render a separated lighting pass to compensate the shadows, this goes with my first point.

 

Having said all that, lighting is very tricky, I understand the need of having a 'day' rendering but, photographing a building in the middle of the day is the worse case scenario most of the time, you have to harsh contrast, very dark shadows and very bright areas. To better understand the shape of a building you need to study what time of the day the light work best for that building. is not a magic number is a per case scenario. and that's why Arch Viz is more an art that a science. We need to be flexible enough and adjust what need it to get the image that we look for.

[D C]

Regarding HDRI, this it been talked a few times here, and the truth is about 80% of HDRI you find online are not well processed. They are not as High dynamic range as they pretend to be, when using those images is when you get bluish tinted renders, lack of contrast on shadows and other problems. If you use a well prepared HDRI to lit your scene it will have a consistent sun shadows, nice reflections glossiness and everything that Environmental lighting will give you. You can also render a separated lighting pass to compensate the shadows, this goes with my first point.

 

We always stick to reputable sources, Peter Guthrie/Vizpeople. From what I understand these are high quality after extensive research.

 

I don't suppose you have used either of these suppliers in your workflow? If not I would be interested in hearing those that you do.

[beestee]

I have used and been very happy with Peter Guthrie's HDRIs for many years. Thomas Suurland's work is also top tier, and he has also made his HDRIs available.

 

I have not used vizpeople, but looking at them they do look like they would work really well. I like that the vizpeople products have some good horizon content baked in since getting that transition just right at the horizon can be time consuming. It is also nice that they provide a sample so that you can see if you can get it work before purchasing.

[Francisco Penaloza]

We always stick to reputable sources, Peter Guthrie/Vizpeople. From what I understand these are high quality after extensive research.

 

I don't suppose you have used either of these suppliers in your workflow? If not I would be interested in hearing those that you do.

 

Yes I own a several HDRI from different sources, but usually I use mostly from Hiperfocal or CG Source

I have a few from Gutrie, but they used to have a constant bluish tint, the latest made are much better.

 

http://www.hyperfocaldesign.com/hdri-sky/

 

cg-source.com

[Tom Sproule]

Yeah, I would have to agree with the others. Sorry I didn't get back to you earlier. I've used Peter Guthries and Viz People, I do sometimes edit the HDRIs in photoshop to increase the sun and adjust the hue. Or I add a colour correction in the material editor and decrease the saturation of the HDRI that way.

 

I'd have to agree with C G and say you should definately add in fake lights to add colour and lighting. One of our guys will often have a light in front of the building near the ground which is somewhat orangey and will fake bounced light off the forecourt, and then he'll add a blue light towards the top to create the illusion of blue from the sky.

 

The best solution would probably be to find a photo or image you like and try and replicate it. by adding in various light types and see what result you get and what you like.

 

With HDRI's I will often go through four or five or more to find the one I like. I'll also adjust Inverese Gamma to adjust the brightness of the sun. But know that lowering this amount will also put more colour and saturation into your image.

 

Best, Tom

[D C]

I'd have to agree with C G and say you should definately add in fake lights to add colour and lighting. One of our guys will often have a light in front of the building near the ground which is somewhat orangey and will fake bounced light off the forecourt, and then he'll add a blue light towards the top to create the illusion of blue from the sky.

 

 

Best, Tom

 

He'll do this on daytime visuals?

[Tom Sproule]

Yes. If you think of a driveway in front of a house on a bright, sunny day, it will often reflect the sunlight back up onto the building. So, he'll add in a light to fake the light reflecting off the driveway. It can add in great contrast to the facade.

[notamondayfan]

I'd also add that with the lack of interesting lighting, as most day time shots are simple by definition, the view immediatly scrutinises everything else in the shot. Architecutre, materials, props, foliage all become the attention, and if each of these aren't perfect it will take away from the realness of the shot.

 

Take time to perfect the small parts, the finer detail, and then build upon it. No ammount of post process glows, fake lighting, etc will make up for shit hot modelling and textures.

 

I work to the concept that....

 

Lighting makes things look interesting.

Modelling makes things look right.

Texture / shaders make things look real.

 

You can perhaps get away with 1 of these areas not being 100%, but as soon as 2 of these areas drop below 100% then you soon become unstuck.