"ROADSIDE" NWDA IMAGE CHALANGE ~ Richard Fraser

Started by cyphyr, February 24, 2013, 12:53:43 PM

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cyphyr

#45
Sorted out most of last nights problems.
A few ideas on lighting the scene a little more dramatically.
(inspired in part by some photos I saw on the Nikon site).
Now if I can just get in some god rays ...
Cheers
Richard
here's a link to the image that set me off in this direction.  It's on Facebook but you should be able to see it as it's a public gallery.
www.richardfraservfx.com
https://www.facebook.com/RichardFraserVFX/
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Ryzen 9 5950X OC@4Ghz, 64Gb (TG4 benchmark 4:13)

Dune

It's going to be (already is) a beauty, Richard. Did you use a non-visible cloud layer (shadow cloud) for the extra shadows?

cyphyr

Quote from: Dune on March 12, 2013, 03:48:03 AM
... Did you use a non-visible cloud layer (shadow cloud) for the extra shadows?
No all the cloud layers are fully visible, although of course now I'll have to experiment!

I had a minor realization. Terragens camera is a ... wait for it, this is awesome, a camera! Wow breakthrough stuff eh. The point being though that as with a normal camera you can mess with the exposure. Usually the only time i do this is to bring up the exposure because a scene has become too dark, I don't think I've ever dropped the exposure because a scene was too light. Well looking at the image in the link I posted above and the photographers site I saw that many of his images were taken looking directly into the sun, generally a big no no in photography. He must have lowered the exposure (amongst other settings). So I got to thinking what if I did the same in Terragen, I could have the sun in front of the camera, make it really bright (I think it's set at 14!) and drop the exposure to compensate (-2). Below is the result. It's a little similar to bringing up the contrast but also a little different. Worth perusing I think.

All that said I still feel the scene is missing something, it's become prosaic and rather dull :( Something is missing, a foreground element on the right, a lightening bolt in the distance,I don't know ... suggestions on a postcard :)

Any C&C very welcome.

Cheers

Richard
www.richardfraservfx.com
https://www.facebook.com/RichardFraserVFX/
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Ryzen 9 5950X OC@4Ghz, 64Gb (TG4 benchmark 4:13)

Tangled-Universe

Oh oh...you may have an issue now, now when your scene is set up and developed with such an uncommon setting for sun's strength.
It depends a lot on the atmosphere on how the shading of the terrain works out as well as the lighting for the clouds, but there's a slim chance you may need to rework your entire surface shaders network and your clouds (the least of work) to get it to work with normal sun's strength values.
I can imagine all may respond differently with the lowered exposure or lowererd sun's strength, but let's hope it's all fine and just a matter of rebalancing the camera exposure with sun's strength.
Why did you use such a value for sun's strength in the beginning, I'm wondering?

cyphyr

Quote from: Tangled-Universe on March 12, 2013, 05:39:55 AM
...
Why did you use such a value for sun's strength in the beginning, I'm wondering?

Just experimenting really, treating Terragen as a camera. I'm using relatively high GI settings to bring out the detail in the shadows (3,4,8, Super sample and GI Surface detail ticked) so the experimentation is a slow process.
Of course your right I probably will have to re-work the shaders to an extent. I may remove them all entirely and just leave the displacement component, get the lighting better and then start to put the colour back in.
cheers
]Richard
www.richardfraservfx.com
https://www.facebook.com/RichardFraserVFX/
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Ryzen 9 5950X OC@4Ghz, 64Gb (TG4 benchmark 4:13)

Hetzen

It's looking great Richard. Sometimes you do need to dial the sun up to get any GI light under thick atmospheres. It would be good to know best practice here, on whether to compensate with textures or exposure.

When I saw this last night I thought that some rain squals might look good, or at really darken down the horizon on the right.

Tangled-Universe

I feel with you Richard. Especially due to recent discussion in the realism thread you may become excited trying these things.

Usually I stick pretty much to the default values and do not deviate too much from them.
For sun's strength I sometimes bring it down to 3 and sometimes up to 5, but not more.
Only one exception: sunsets. There I tend to use values of around 10 or more, especially with very low sun elevations.

What you may try indeed is disabling the surface shader chain and re-balance that lighting, then re-enable surface shaders and see if they hold up.
If you need to make the surfaces darker/brighter then you can save yourself a lot of time by feeding the entire surface shaders chain as colour input of a surface layer and use the diffuse colour setting as multiplier for diffuse colour brightness. Very handy.

Another thing I often stick too is that I always use max albedo 100% for my clouds (0.25 for colour, that is).
Then I adjust lighting in such a way that my EXR can contain the cloud's brightness easily. Say about 3/4-way of the histogram.
Even in EXR you can get over-exposed areas of atmosphere easily.
If it's about 3/4-way of  the histogram you can push/pull it a bit when playing with exposure/gamma.

This all depends on your area of interest of course. Now I'm discussing mostly atmosphere, don't know why actually :)
The area of interest in this contest is roads and thus surfaces, so for the moment I would base these kind of decisions for your surfaces.

So in retrospect, you may not need to refine all your surfaces, but only set sun strength to default, adjust camera exposure (for vegetation mostly) and then refine atmosphere. Perhaps that's the most effective approach?

Good luck!

j meyer

Quote from: cyphyr on March 12, 2013, 05:31:45 AM
....
All that said I still feel the scene is missing something, it's become prosaic and rather dull :( Something is missing, a foreground element on the right, a lightening bolt in the distance,I don't know ... suggestions on a postcard :)
...

How about a hint to a cause for the look on the right side?
Maybe something toxic or a bomb crater or so.
Keep it up,J.

Dune

Perhaps a last dust tornado leaving the devastated area, minor if in front, or huge when near the dark clouds far off.

Matt

Martin, Richard,

Don't worry about increasing sunlight strength and decreasing exposure. You're not doing any harm. But it's also a bit pointless ;) If you only have a sunlight and GI in your scene (no other light sources, ambient lighting or luminous surfaces) then sunlight strength and camera exposure have exactly the same effect on the final image. Doubling sunlight strength will double the brightness of everything, because there are only two sources of light: direct sunlight and GI. Because GI is scattered or reflected sunlight, its brightness changes as sunlight strength changes, so changing the sunlight changes the brightness of everything. Camera exposure is a final multiplier for the whole image. So if you double the sunlight strength while halving the camera exposure then you will produce exactly the same image.


However, if you use the ambient controls in your clouds or atmosphere, they are separate from sunlight. Enviro Lights set to "ambient occlusion" mode are also independent of sunlight, as are additional light sources and surfaces with luminosity. Therefore, if you want your scenes to be reusable with other assets that have light sources or luminous surfaces it's still a good idea to think of the sun as a constant in the world, keep its strength at the default 3.5 and use camera exposure to control your image.


Matt
Just because milk is white doesn't mean that clouds are made of milk.

Tangled-Universe


cyphyr

I've been battling with clouds all week with only some success. I want a BIG complex pre-storm sky, something like you'd get in Africa.
I've used different cloud colours to see more easily what cloud element is doing what to the scene, it helps a "little" ...
Any suggestions for decent complex cloud scenes gratefully received.

Cheers

Richard
www.richardfraservfx.com
https://www.facebook.com/RichardFraserVFX/
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Ryzen 9 5950X OC@4Ghz, 64Gb (TG4 benchmark 4:13)

Tangled-Universe


cyphyr

Kind of, but I'm looking for that "ordered chaos" look. Regimented ranks of low cumulus clouds, higher wind swept stratos clouds coming off the tops of massive cumulonimbus calvus, that sort of thing, a little ambitious maybe but I'm not dooing anything else atm.
Cheers
Richard
www.richardfraservfx.com
https://www.facebook.com/RichardFraserVFX/
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Ryzen 9 5950X OC@4Ghz, 64Gb (TG4 benchmark 4:13)

Tangled-Universe

Yes this setup contains pretty much all of those elements, except for the calvus like cumulus...although I agree it doesn't have this kind of orderly look you're talking about :)

The Africa-like blu'ish developing storms is something I tried here too though.
Basically you can achieve these effects by altering the enviro light colour in the cloud node.