WIP - First Arrival to Alpha Cassiopeiae

Started by N-drju, May 12, 2020, 02:30:53 pm

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N-drju

Greetings! Welcome to my NWDA contest image WIP thread.

This will be my first art contest ever and I am really excited about it. Travel constitutes a large portion of my "daytime job" as well, so when I heard about this year's theme... well, I just had to join the fun. Being an astronomy enthusiast too, I have chosen space travel as the setting of my entry.

So without further ado, enter stage left - First Arrival to Alpha Cassiopeiae:

NWDA 1.jpg

For those who care about such details - Alpha Cassiopeiae is a red giant star. Scientist argue whether life can develop on planets that orbit such huge stars.

Some models indicate that if a planet is far away enough and, at the same time, the star is not excessively massive, such worlds could have free water and temperatures that are "just right" to support multicellular life. The optimistic time span for these conditions to last is 2 - 5 billion years. Enough for life to develop.

Therefore, I will attempt to create a landscape of a planet which has just recently joined the CHZ Club, but has all it takes to support a thriving ecosystem in the near future. Above its surface, three recon crafts (placeholders for now) travelling above a water-filled canyon, exploring the new world.


C&C are welcome. :)
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

I will wait with C&C until you are a bit further, but will wish you luck on your first art contest! Make it spectacular! So maybe a little C&C; choose a POV that allows for some foreground, creating depth, even if it's another recon vehicle.

N-drju

Thank you for nice words Ulco. Yes, the foreground is quite poor in this iteration and will be reworked into something else. Perhaps a low ground or, if the cliff stays, a less-warped edge.

By the way, if anyone wants to have a look, here is a comparison of the water gauze in a standard and PT render that I questioned earlier. As you can see, the standard render produces a blurry shadow edge which, at least in my view, is closer to reality. It gives a feeling as if something is indeed "happening" in the water in terms of particulate matter.

STD.jpg

And now the PT version - shadows are completely flat and suspiciously perfect (interestingly, the water is also brighter). I'm afraid nature doesn't quite work this way.

PT.jpg
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

Perhaps de blurryness in the standard render comes from the RDM of 0.25. But you're right, the PT needs work to get nicer. Maybe set smoother shadows and increase roughness of reflection?

Matt

What mode are you using for "Lighting method in PT"? The subsurface scattering options should cause blurring, while "Hard surface approximation" will give you a sharp shadow. For bodies of water I would use "Subsurface scatter towards normal" - this should be the default for the Water Shader.
Just because milk is white doesn't mean that clouds are made of milk.

N-drju

Quote from: Matt on May 13, 2020, 04:51:52 amWhat mode are you using for "Lighting method in PT"? The subsurface scattering options should cause blurring, while "Hard surface approximation" will give you a sharp shadow. For bodies of water I would use "Subsurface scatter towards normal" - this should be the default for the Water Shader.

In fact, it is set to "SS towards normal". Here are my water settings:

water set.jpg

I'll have a go and see if RDM is indeed affecting the shadow projection. There's still plenty of time to set it right of course.
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

Btw, index of 1.65 is not normal for water, should be is 1.33. But you may have a reason (interstellar differences).

N-drju

Quote from: Dune on May 13, 2020, 10:18:28 amBtw, index of 1.65 is not normal for water, should be is 1.33. But you may have a reason (interstellar differences).

Oh... I just googled it and I didn't even know the refraction values are scientifically defined! Thank you. I changed it back.

And no - I don't think extraterrestrial water would be any different.
:)
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

DannyG

New World Digital Art
www.NwdaGroup.com
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WAS

May 14, 2020, 03:01:13 am #9 Last Edit: May 14, 2020, 03:20:56 am by WAS
Quote from: N-drju on May 13, 2020, 11:55:32 am
Quote from: Dune on May 13, 2020, 10:18:28 amBtw, index of 1.65 is not normal for water, should be is 1.33. But you may have a reason (interstellar differences).

Oh... I just googled it and I didn't even know the refraction values are scientifically defined! Thank you. I changed it back.

And no - I don't think extraterrestrial water would be any different.
:)

TG index of refraction values do not match scientific values at all FYI. Waaaay off from scanned readings for many materials, most especially being reflective. It's more correct for dull materials. For example some rock minerals I looked up were around 1.12 which, actually does look "rock-like" when used for rock reflection. I think TG is like Unity/Unreal and other engines where they're approximations based on what works. FOr metal, in TG for example, IOR needs to be ridiculously high to match physical appearance, way off the charts for scientific readings.

The water in the PT looks better depth wise imo but the shadows are bizarre. I like that cliff side color control. Nice slip zone.

N-drju

Quote from: WAS on May 14, 2020, 03:01:13 amTG index of refraction values do not match scientific values at all FYI. Waaaay off from scanned readings for many materials, most especially being reflective. It's more correct for dull materials. For example some rock minerals I looked up were around 1.12 which, actually does look "rock-like" when used for rock reflection. I think TG is like Unity/Unreal and other engines where they're approximations based on what works. FOr metal, in TG for example, IOR needs to be ridiculously high to match physical appearance, way off the charts for scientific readings.

The water in the PT looks better depth wise imo but the shadows are bizarre. I like that cliff side color control. Nice slip zone.

Thanks Jordan. I like the cliff shapes too. I plan too add even more detail though I have to remember not to exaggerate it...

I know - IOR may not be 100% realistic in CG, but I have to rely on something, so I'll just stick to 1.33 for now. :) In fact, the water indeed looks more life-like at this value.

Here is another small update. I have added some terrain on the right bank and changed POV to obtain foreground like Ulco suggested. It looks like it was a good decision. I'll have to fine-tune it though, because the cliff is obstructing the crafts' shadows. By the way, I have replaced placeholders with the actual craft shapes... Not at all satisfied with them. >:( I'll have to reconsider the design...

As far as colours go, I have just noticed that the soil colour is cut out abruptly in the foreground section so I'll have to work on that too:


NWDA 2.jpg
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

You could go even closer to get a really close foreground 'something'. With a bit of DOF that could look awesome. I have sometimes used just a few meter cube or sphere hanging right in front of the camera (you can place it by hand), with some displacement, texture and veggies popped on.

Matt

Quote from: WAS on May 14, 2020, 03:01:13 amTG index of refraction values do not match scientific values at all FYI. Waaaay off from scanned readings for many materials, most especially being reflective. It's more correct for dull materials. For example some rock minerals I looked up were around 1.12 which, actually does look "rock-like" when used for rock reflection. I think TG is like Unity/Unreal and other engines where they're approximations based on what works. FOr metal, in TG for example, IOR needs to be ridiculously high to match physical appearance, way off the charts for scientific readings.

You are generalizing here. It's only metals that are "way off" because metals behave differently from dielectrics. Dielectrics (most materials) should correspond quite closely to IOR tables. Terragen 4.5 has a metalness parameter so you won't need to use high IOR for metals much longer.
Just because milk is white doesn't mean that clouds are made of milk.

WAS

May 14, 2020, 06:06:59 pm #13 Last Edit: May 14, 2020, 06:22:02 pm by WAS
Quote from: Matt on May 14, 2020, 12:08:42 pmYou are generalizing here. It's only metals that are "way off" because metals behave differently from dielectrics. Dielectrics (most materials) should correspond quite closely to IOR tables.

I don't really understand that, considering the scientific data on metals, or other reflective surfaces. It's really down to the wavelength, isn't it? And using generalized one things don't match up from one to the other. And I believe you really just generalized what I generalized. Dull materials are more correct than reflective. The constant for generalized metals, for example is 1.6670, and wouldn't work in TG, same for crystals at 2.3866, even some dull materials don't align where a constant of 1.4260 for clay montmorillonite powder wouldn't work in TG and would be nearly as reflective as glass.

Isn't this why all the tables out there have a 3D and Graphics generalized table?

Also some things depend on other properties. Like water. Water at 20c has a ior of 1.33.

Matt

May 14, 2020, 08:43:34 pm #14 Last Edit: May 14, 2020, 08:48:27 pm by Matt
This discussion belongs in a different thread so I'm going to split it. Edit: No I'm not, it's too complicated already.
Just because milk is white doesn't mean that clouds are made of milk.