Grainy render ?

Started by zooropa, April 01, 2018, 04:09:34 AM

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Will Gibbons

I think what Dries was suggesting was if you could sweep/loft the profile along a spline to create this geometry with a single surface, it should be much faster to render. Of course, then you'd need to assign UVs to the geometry to make the texture work they way you want it I believe.

zooropa

Quote from: Will Gibbons on April 05, 2018, 07:55:16 AM
I think what Dries was suggesting was if you could sweep/loft the profile along a spline to create this geometry with a single surface, it should be much faster to render. Of course, then you'd need to assign UVs to the geometry to make the texture work they way you want it I believe.

oh yes.. Unfortunately Rhino for mac does not support uving...

zooropa

#17
Quote from: mattjgerard on April 03, 2018, 08:30:03 AM
So, interior mode shows fantastic results in the shadows after only about 2 min. Its running at about 15 fps on my machien ad after 120 seconds it reaches about 100 samples .  I reduced the size of the region window and at about 200 samples, the shadows were buttery smooth, no noise, perfect gradients.

I also cranked down the number of GI bounces, as there aren't any highly reflective surfaces in the scene,  as well as the ray bounces, reduced that to 2, and didn't seem to affect the image, but the FPS jumped up a bit.

Now, I understand that those settings might not hold up with other objects in the scene, but just using your ball setup, making those tweaks seemed to get some good results.

I tried the new product mode as well, but as with the other product mode, even though my fps went up to 149, it took even longer to resolve a smooth noise-free shadow, so I think your solution is to use interior mode.


I did another check with interior mode...you are right...just works better...and it is not slower (not in my scene at least). The shadows look better and convince me more than the Product mode.
Please check the attachment.

Also want to add that the backdrop ramp has a different bump...so the noise is not particular a problem in comparison. It is just that It looks floating...the shadows are not accurate at all.

I remember that Esben had a tip about making the pin smaller to get more defined shadows...but I find the method a little bit counter intuitive. I am not an expert in lighting and hacking this to a small source without loosing the reflection is not easy for me.



mattjgerard

That's looking a lot better!

Smaller light source = sharper shadows
Larger light source = diffuse shadows

You can have both by having both large lighting features in your HDRI and get the sharper shadows by 1) adding smaller, brighter pin lights or 2) Adding IES practical lights to the scene. I personally find manipulating practical in-scene physical lights easier, as I'm not totally understanding how HDRI lighting works, so I usually end up adding spheres and planes with emissive or area light materials or using IES light objects.

In real world studio setups, this image is a good example. I have done 15 years worth of work with Toro on the video side, but the product shooters had the same setup every time. Huge overhead softboxes to cast general lighting and soft shadows, then practical floor lamps to hit features of the mowers and to cast those sharper shadows that would glue the product to the white floor and keep it from looking like it was floating.

https://www.toro.com/en/golf/fairway-mowers/reelmaster-3550

zooropa

#19
Quote from: mattjgerard on April 06, 2018, 06:40:18 AM
That's looking a lot better!

Smaller light source = sharper shadows
Larger light source = diffuse shadows

You can have both by having both large lighting features in your HDRI and get the sharper shadows by 1) adding smaller, brighter pin lights or 2) Adding IES practical lights to the scene. I personally find manipulating practical in-scene physical lights easier, as I'm not totally understanding how HDRI lighting works, so I usually end up adding spheres and planes with emissive or area light materials or using IES light objects.

In real world studio setups, this image is a good example. I have done 15 years worth of work with Toro on the video side, but the product shooters had the same setup every time. Huge overhead softboxes to cast general lighting and soft shadows, then practical floor lamps to hit features of the mowers and to cast those sharper shadows that would glue the product to the white floor and keep it from looking like it was floating.

https://www.toro.com/en/golf/fairway-mowers/reelmaster-3550

Added just for a test of a new scene.

Trying to follow your tip, think also Esben mention to me too.

I duplicated one light source and make it smaller and extremely brighter...
You can check the printscren, It is not working at all ...I do not know what happens with me this week ...but KS and I are not getting along.


Will Gibbons

Actually, Rhino does support UVing.

Here's an old video showing the process: https://www.youtube.com/watch?v=75cQX-iF8YA

As for the small pin... I think you made it too small. Turn off the big pin and make the pin size 5 and brightness 100. Should work. If your big pin is too bright, it's going to make the shadow of the small pin too difficult to see.

Esben Oxholm

Quote from: zooropa on April 06, 2018, 12:03:41 AM
I remember that Esben had a tip about making the pin smaller to get more defined shadows...but I find the method a little bit counter intuitive. I am not an expert in lighting and hacking this to a small source without loosing the reflection is not easy for me.

If you have trouble wrapping your head around the concept, then just think of the sun and a cloudy sky. Might help.
The sun (which is a tiny dot compared to the large sky) creates sharp defined shadows, while the cloudy sky (which covers a large area) creates soft shadows.

You'll need to have both to have clear defined shadows and larger reflections on your object as Matt states.

As for your latest test, I would try to make the small pin bigger as Will suggests. I really need something smaller than pin size 1.


Quote from: mattjgerard on April 06, 2018, 06:40:18 AM
In real world studio setups, this image is a good example. I have done 15 years worth of work with Toro on the video side, but the product shooters had the same setup every time. Huge overhead softboxes to cast general lighting and soft shadows, then practical floor lamps to hit features of the mowers and to cast those sharper shadows that would glue the product to the white floor and keep it from looking like it was floating.

https://www.toro.com/en/golf/fairway-mowers/reelmaster-3550
Cool example, Matt! I would have guessed it was a rendering if someone had asked. Pretty interesting.

zooropa

Quote from: Will Gibbons on April 06, 2018, 08:15:51 AM
Actually, Rhino does support UVing.

Here's an old video showing the process: https://www.youtube.com/watch?v=75cQX-iF8YA

As for the small pin... I think you made it too small. Turn off the big pin and make the pin size 5 and brightness 100. Should work. If your big pin is too bright, it's going to make the shadow of the small pin too difficult to see.

Thanks Will! Worked with the value at 25000 like Esben videos!

zooropa

Quote from: Esben Oxholm on April 07, 2018, 08:18:43 AM
Quote from: zooropa on April 06, 2018, 12:03:41 AM
I remember that Esben had a tip about making the pin smaller to get more defined shadows...but I find the method a little bit counter intuitive. I am not an expert in lighting and hacking this to a small source without loosing the reflection is not easy for me.

If you have trouble wrapping your head around the concept, then just think of the sun and a cloudy sky. Might help.
The sun (which is a tiny dot compared to the large sky) creates sharp defined shadows, while the cloudy sky (which covers a large area) creates soft shadows.

You'll need to have both to have clear defined shadows and larger reflections on your object as Matt states.

As for your latest test, I would try to make the small pin bigger as Will suggests. I really need something smaller than pin size 1.


Quote from: mattjgerard on April 06, 2018, 06:40:18 AM
In real world studio setups, this image is a good example. I have done 15 years worth of work with Toro on the video side, but the product shooters had the same setup every time. Huge overhead softboxes to cast general lighting and soft shadows, then practical floor lamps to hit features of the mowers and to cast those sharper shadows that would glue the product to the white floor and keep it from looking like it was floating.

https://www.toro.com/en/golf/fairway-mowers/reelmaster-3550
Cool example, Matt! I would have guessed it was a rendering if someone had asked. Pretty interesting.

Thanks Esben getting there...Still trying to manage the shadow on the plants. I guess a little bit more of work...also on the textures