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Panorama - 50 Shaders of Grey


Mark Aceto

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Thanks to VW Cloud Services cloud rendering, I'm getting reacquainted with Renderworks. Also, how is cloud rendering not the headline screaming from the mountain tops right now? I feel like I have a Threadripper with a 3080 next to my 6-year old MBP that's quietly letting me edit the model while multiple renders are being processed in the background (multitasking heaven).

 

I've watched the VW tutorials, and referenced @Andy Broomell's excellent guide to texture creation (that fills in all the undocumented explanations and techniques) but I'm having a bit of a design paradox... 

 

Client is converting an old venue into a black box. We're doing demo work, exposing brick walls, removing walls, keeping the art deco drop ceiling soffit feature... so I'm helping them visualize that transformation but I'm running into some design decision challenges:

  • True black textures seem to create a light-sucking void into a fourth dimension, so I've stopped them all at 1% (versus 0%)
  • Brick textures are bumped, parrallaxed, and displacement mapped but I'm not really seeing it because of the LX choices I've made
  • Color Force IES files were not visible at all as custom light sources
  • I tried a couple S4's but the file started freaking out, so I wanted to keep it simple for this round by using Light Source objects
    • Maybe I should reconsider that choice for Renderworks vs OpenGL?
      • Point lights in OpenGL worked great but they're kinda boring in a final render
      • Spot lights in OpenGL had amazing punch (and a chromatic vibrance) but cannot show bump or displacement mapping (plus limited to 8 lights)
  • Lit fog is usually my friend but it just mutes everything here, and hides the ceiling soffit
  • The more light bounces around the room, the greyer the room gets (makes sense)
    • Reflection is 0-3% on most textures
    • Blur is in the 5-10% range
  • Trying to find a balance of light scraping the bumped / displaced brick but the beam / field angles have a soft edge
  • At one point, I added "neon tube" tucked in the soffit (extrude along path with a glow texture) but I felt like that was faking it too much
    • Maybe that's something I should continue exploring?

Once we have a show in there, the black box will fade into the background as it should, so this is a strange challenge. I could add the existing work lights for accuracy, which I will in the next round but I doubt that will look very sexy.

 

I guess what I expected was hoping for was more of a glossy black look than a neutral grey... When I had reflections turned up, it was still grey but mirrored on the floor, walls and ceiling.

 

Maybe the solution is repositioning the lights closer to the walls, so they'll scrape the bricks (instead of washing them out at 45º tilt) because the trade-off of the beam spilling onto the floor is worth it... I'll say it's "dramatic" instead of unintentional. And use a plastic reflection on the painted black brick wall texture (similar to the one that I created for the truss).

 

Thanks in advance to the 3D artist render masters here in the forum!

 

The pano link below is best viewed on a phone or table (or Google cardboard) in full screen (on Safari: Hide Toolbar), and then tap the screen to hide the control panel:

 

https://cloud.vectorworks.net/links/11eb3086045e75ca89a10aa721e465bf/

 

Test Pano.jpg

Edited by Mark Aceto
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Getting warmer... 

 

https://cloud.vectorworks.net/links/11eb31531efd2cc89ae412923fa32d81/

 

598328250_TestPanov02.thumb.jpg.0efc106b2b4b08144f79dc8460793c31.jpg

 

Using image effects to B&W the stock brick image, and then inverting it helped with the bump. Now that I understand that I need the bricks to be light and the grout to be dark, I could bring back displacement mapping (if I was less concerned about render times in this fairly brick-heavy model; maybe as a last step in the final rev).

 

I was able to get the Studio Force IES file to work but it looked way too corny for this purpose. It was definitely the best example of contrast without that muted neutral gray washed out look though (obviously scraping bricks with strips is always the best for revealing the texture of the exposed bricks. Speaking of IES files and strips, I really wish we could still import them into Spotlight lighting devices... 

 

1660103354_TestPanoStrips.thumb.jpg.e9a47218969d58cb4088d06a6283baac.jpg

 

S4's worked too but I ultimately went with spots (which are actually the same light sources that lives inside the S4). Shutter cutting wasn't as necessary as I thought it would be for this exercise. Actually, it is starting to bother me looking that them side by side... 

 

Test Pano S4.jpg

 

One key learning for me is that I'll instinctively want to blame the object -- "there's a bug", "something must be corrupt", quit and restart (always worth a shot) -- but then I'll discover something random like having a heliodon outside the building leaking light through a doorway and causing havoc (as in the case below). Look at how the spot beams washing the floor look correct but where the beam scrapes the brick, it's actually a shadow (far left light in the image is the most extreme because there's an doorway facing it on the other side of the building):

 

Test Pano CA.jpg


Simplifying the number of bounces and reflections helped isolate the cause and effect. More isn't always better. I suspect that's one of the reasons OpenGL is so pleasing. KISS

 

Edited by Mark Aceto
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Are you sure that GI is what you want for this type of presentation?  You have a lot of negative space and most of those bounces are so low energy there is no real need for them.  I usually like to start off with a little bit of ambient light and ambient occlusion, to get the feel of the shots.  If GI really seems necessary, add it back in and remove the former.  But it is not the magic wand that most people think it is.  There might be more reward in setting up your cameras with different exposures.  

 

Black textures should never be completely black, and all textures should be "rich" in that they should contain at least some measure of all three pixel colors.  While it is true that all surfaces are reflective to some degree, I often question the merits of adding in reflectivity to everything.  Again, I would start off with reflectivity disabled, then add it back in and see if the increased render times are worth it. 

 

Overall I think your panorama is quite nicely rendered.  But it is important to ask at what point in time you are trying to make this rendering come from. To me it looks like what you would see the first 10 seconds you walked into this room from another, lit room.  But after a few more seconds of being in the room your eye would adjust to the low levels of lighting and you would see more.  A photographer might capture this by opening up the lens and gathering more information (hence my note above about exposures).

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10 hours ago, Tom W. said:

Just like to say I also think Andy Broomell's guides are excellent. I'd not seen this one on textures so thanks for sharing.

 

I think I found the link here in the forum, so I'm bookmarking it for later.

 

Wait -- now I'm wondering what other easter eggs there are on his site... 

 

Edited by Mark Aceto
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5 hours ago, grant_PD said:

Are you sure that GI is what you want for this type of presentation?  You have a lot of negative space and most of those bounces are so low energy there is no real need for them.  I usually like to start off with a little bit of ambient light and ambient occlusion, to get the feel of the shots.  If GI really seems necessary, add it back in and remove the former.  But it is not the magic wand that most people think it is.

 

Thanks -- these are great notes!

 

These are my GI settings (haven't saved it as a style yet). I'm OK with dropping it to 1% but my understanding is that turning it off can have some negative side effects with other textures and FX.

 

1835820376_ScreenShot2020-11-28at9_45_34AM.thumb.png.91418ba3704fba1c26d2ce96cd598bcc.png

 

5 hours ago, grant_PD said:

There might be more reward in setting up your cameras with different exposures.  

 

This is a 360 pano for viewing on a phone or tablet, so I only used a camera to set the origin, and then deleted it.

 

I'm reposting the link here: https://cloud.vectorworks.net/links/11eb31531efd2cc89ae412923fa32d81/

 

5 hours ago, grant_PD said:

Black textures should never be completely black, and all textures should be "rich" in that they should contain at least some measure of all three pixel colors.  While it is true that all surfaces are reflective to some degree, I often question the merits of adding in reflectivity to everything.  Again, I would start off with reflectivity disabled, then add it back in and see if the increased render times are worth it.

 

Thank you! I don't understand why this is or where it's documented but I've set all my "black" colors to 1% (99% black) in the color picker. However...  what I've discovered is that a non-reflective black surface will turn into flat grey and then white very quickly as the lighting intensity increases. That's where Andy's guide helped out with the plastic settings but it only works on curved surfaces. In my render, you'll notice that black truss and round walls are fairly successful examples of this. FWIW I started with the same procedure you mentioned, starting at 0%, and maxed it out at 3% with all textures (and blur up to 20%).  Here's the section that helped me understand that:

 

370689548_ScreenShot2020-11-28at9_53_42AM.thumb.png.8e83b8007d34a432c9ae105226a0c520.png

 

5 hours ago, grant_PD said:

To me it looks like what you would see the first 10 seconds you walked into this room from another, lit room.  But after a few more seconds of being in the room your eye would adjust to the low levels of lighting and you would see more.  A photographer might capture this by opening up the lens and gathering more information (hence my note above about exposures).

 

Yes -- exactly! This is such a great way of describing what I've been trying to solve! Increasing exposure time "lets more light in" but doesn't add watts / lumens / foot candles...  And black objects don't turn grey when our eyes adjust... 

 

I was thinking this exercise is a lot like audio engineering. If I had a PA at one side of the room with the mains shooting directly at the other side of the room, there'd be "slap back" (reflection). And it would also reflect off the side walls, floor and ceiling too. The way to overcome that is to place a lot of smaller low powered point source speakers in the room instead of a few high powered array speakers. Speakers and lights both have beams/dispersion angles, falloff, reflection... Even the language is the same. At the moment, I have 4 point lights running down the center of the room, and hot spots at either end. Each point light is set to 400 with a smooth falloff. I'm wondering if I should use 16 points lights set to 50 (like the point source audio engineering example). I'm picturing what a LIDAR camera sees but offset 5' from each wall. Then I wouldn't be blowing out the walls at either end, and I could just highlight the ceiling and walls as necessary with greater control / modulation.

 

BTW maybe your note about exposure could be a feature request for future versions of the 360 pano export (unless it already exists and I missed it). I would love an option for longer exposure vs brighter lights.

 

537473434_ScreenShot2020-11-28at10_03_57AM.thumb.png.f26f204db465341673b862b85505219a.png

Edited by Mark Aceto
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Yes, your soft lights are spheres of light, and since you can't control the falloff (in VW) you can only play with the intensity/distance to get them to read less.  I have worked with files were there was literally hundreds of omni lights all at 15% all throughout the room.  Here's a quick test of showing 4 surfaces illuminated only by 1 point light at their intersection.  Clockwise from 9 oclock each quadrant's rgb values are: 0,0,0/10,10,10/20,20,20/30,30,30.  I started the point light at 12' above, then moved down by 3' each time.  While it's true that the true black never turned grey, in real life that would never happen.  So you must choose where your black point is and adjust.  

 

An array of lights would give a more even look, hence the use of area lights.  I'm not sure if panoramas support those lights.  

Blacktest3.jpg

Blacktest1.jpg

Blacktest2.jpg

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@grant_PD thanks for the feedback -- this is super helpful!

 

I was thinking about the exposure analogy, and it seems like a longer exposure increases a uniformly distributed volume of light as compared to a flash which increases the intensity. Having a few point lights in the model is more like a flash that creates hotspots. If that's true, then the pano export ostensibly already supports a "long exposure".

 

Excited to try the array method next... If everything works like I hope, I can refocus my spots in the position I originally had them where I couldn't figure out what was wrong in half of them (presumably crazy aberrations from other light sources bouncing around the room vs an issue with the spots themselves).

 

Edited by Mark Aceto
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11 hours ago, Mark Aceto said:

 

I think I found the link here in the forum, so I'm bookmarking it for later.

 

Wait -- now I'm wondering what other easter eggs there are on his site... 

 

 

Glad you found my texture guide helpful! That page and a few others are actually unlisted on my website; they happen to be take-home guides for classes that I teach. I'm considering adding a few of them to my public "Resources" page though 🙂

 

https://www.andybroomell.com/resources

 

By the way, there's a spot to enter your email at the bottom of that page for anyone who'd like to be informed when I add new public content (which is not as often as I'd like since work has thankfully picked up recently). But over time I'm definitely hoping to add more stuff!

 

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@Mark Aceto I think you will find that adding more lights in a grid helps for less spotiness.  And you might try building an area light, which I have had some success with in VW.  

I am also a fan of ambient light+ ambient occlusion, which some people say is heresy in this age.  But these are just all tools in your toolkit in my opinion.  I certainly would at least try turning it on before I switched on maximum bounces in a GI solution (I would never turn on maximum bounces in a GI solution 😎).

 

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Half a day, and 20 revisions later, I've come full circle.

 

The black truss still looks great. The round walls still look good.

 

But the fact that Default Instrument Texture on the S4's is white... I'm beyond frustrated. I know it's caused by the Point lights. I think the only way around that would be to use Spots on the floor focused up (with smooth falloff), so the beams won't touch the S4's. At one point, I had 32 Point lights in an array but it was washing everything out while also not bright enough. At this point (pardon these puns), I feel like Point lights should only be used sparingly in lazy OpenGL saved views / VP's.

 

I tried to get the Area Light to work but my guess is that tool has been deprecated along with the Line light. Even setting quality to Very High did nothing.

 

I'm wondering if bringing back displacement mapping to the brick texture will help with that flat (albeit bumped) surface... 

 

1535524959_TestPanov03.thumb.jpg.31a9166ff6439b586f3a1cbb8d4d511e.jpg 

Edited by Mark Aceto
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Here's what the model looks like with a totally bottomed out working render style, and no data viz:

 

1621633012_ScreenShot2020-11-30at12_18_06AM.thumb.png.0a8d5d1aa1594178beb9fc4593d68184.png

 

And here's what it looks like with all data viz checked (painted black):

 

[VW crashed and lost 30 min worth of work, and AutoSave didn't save it (including the Saved View that ironically tragically didn't get saved), so suffice to say you would not be able to see any of the lights at all; literally a black void]

 

Basically, I have to ratchet up the lighting brightness "percentage" of all lights to a factor of 4. The S4's that are at 200% in the "before" screenshot are at 800% in the "after" (we paint it black) screenshot. And then all the flat surfaces (and S4's) turn from black to grey.

 

There's just some rendering magic trick I haven't learned yet to light black surfaces... 

 

All of this rendering sparks joy on a 6-year old MacBook Pro driving a 4k display 😕  I need to delete about 50 lights so I can go back to using OpenGL.

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Get reference photos! Our perception is strange and often things are different than we think.
For example, a black surface no longer appears black when it is hit by light. Our brain calculates from the context that a certain light gray surface is actually black.  So don't be afraid that some black surfaces in your picture are white when they are directly under the light source. That is the reality. What you need is context. For example in this first photo: the top wall is almost white under the light. The black wall at this point has practically the same brightness value as the white wall at its brightest point in the second photo. The only difference is the context. Nevertheless, the viewer realizes that the wall in the first foto would actually be black. So what is needed is cleverly placed contexts e.g. some brighter left lying around platforms of the seating, or a brighter floor.

Theatre-Facilities-01.jpg17-Inspiring-Wonderful-Black-and-White-Contemporary-Interior-Designs..jpg

 

Btw: this one is 99% black. So you can use much brighter values for what we consider black in everyday life.

15544779-v0-p90363154-highres-the-bmw-vantablack-x-1.jpg?imwidth=1000&ratio=16_9&x=0&y=75&width=2756&height=1551

Edited by herbieherb
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