Author Topic: Black reflections of lights on low glossiness surfaces  (Read 14834 times)

2016-11-11, 10:08:30

mrsacan

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Now this is interesting,
I have a very simple wall material there.
If I use 1.0 glossiness you can see that spotlights reflect.
But if I use a lower value like 0.66 etc you can see a dark blurred reflection instead of a bright one.

Am I missing something or is this a bug?
« Last Edit: 2016-11-11, 14:57:17 by romullus »

2016-11-11, 10:20:41
Reply #1

pokoy

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I guess this should be move to the bug reports section, looks really wrong. Also, rename the thread to something that catches devs' attention ;)

2016-11-11, 10:32:09
Reply #2

mrsacan

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yea, something wrong about lights I think

2016-11-11, 10:34:17
Reply #3

romullus

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What version you're using? Can you attach simplified scene where this behaviour still reproducible?
I'm not Corona Team member. Everything i say, is my personal opinion only.
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2016-11-11, 10:42:39
Reply #4

pokoy

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Also, does this also happen when visibility for the light is enabled?

2016-11-11, 10:56:24
Reply #5

mrsacan

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version is 1.5 hotfix 1, I attached simplified max file with that room, I think textures don't matter so I didn't include them.

when I select "visible directly" it's still a black reflection in the middle.

2016-11-11, 12:15:41
Reply #6

Nekrobul

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Is Occlude other lights is turned on?
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2016-11-11, 12:41:54
Reply #7

mrsacan

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@nekrobul

no, it's always off if I use as a hidden light

2016-11-11, 14:13:09
Reply #8

Frood

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I remember having this a while ago, as far as I remember that dark reflection was only visible with a glossiness between 0,6-0,9. Had no time to dig deeper, it´s a bug imho. Attached the questionable area, you can see the lights floating in the air used to lighten the logowall as dark reflection. No change in the visibility group could prevent them from appearing. It´s as if the reflection sees a dark light geometry even when "Visible in reflections" is turned off.

Good Luck

Edit: attached minimized scene showing the effect
« Last Edit: 2016-11-11, 14:26:48 by Frood »
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2016-11-11, 14:55:57
Reply #9

romullus

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Ok, renaming and moving this to bug report board.
I'm not Corona Team member. Everything i say, is my personal opinion only.
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2016-11-11, 17:05:52
Reply #10

maru

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This looks like the old "reflection of a refraction" problem, only without the refraction part...
Aleeriza - are you sure that you are using the newest version of Corona? Can you re-install it just to be sure?
Marcin Miodek | chaos-corona.com
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2016-11-14, 07:11:12
Reply #11

mrsacan

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@maru

this morning I downloaded, reinstalled (1.5 hotfix 1) again, unfortunately the bug still exists. It's out there.. Waiting for us.. waiting.. the deadline..

2016-11-14, 15:09:31
Reply #12

maru

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That's strange, but I have problem with reproducing this, even in the submitted scenes. That's why I have some questions:
1. What kind of camera are you using? (or "is this also happening without using vray camera")
2. Is this also happening if camera clipping is disabled?
3. Is this happening only if PBR mode in material's advanced settings is disabled or only if it's enabled?


Ok, works in Frood's scene. Ondra has to check it. The effect only appears if "visible in reflections" is unchecked.
« Last Edit: 2016-11-14, 15:14:45 by maru »
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2016-11-15, 08:56:17
Reply #13

mrsacan

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with hotfix 2 :

2016-11-15, 12:49:08
Reply #14

shadowman

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It seems that the something similar happens in situation when sunlight goes through CoronaLightMtl, "emit light" unchecked.
Got this round shadow on glossy surface..

2016-11-15, 15:29:47
Reply #15

maru

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Well, now we can only wait for Ondra's intervention.
Marcin Miodek | chaos-corona.com
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2016-12-05, 18:26:06
Reply #16

shadowman

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Ok, works in Frood's scene. Ondra has to check it. The effect only appears if "visible in reflections" is unchecked.
Is there something new about this bug?
Was it submitted to mantis?

2016-12-06, 15:32:24
Reply #17

Ondra

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this will be probably a case of "2 fakes not working well together"... let me take a look when I get to debugging ;)
Rendering is magic.How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2016-12-06, 16:04:54
Reply #18

shadowman

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2017-03-29, 16:19:20
Reply #19

shadowman

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Up.
(as it was buried somehow) :)

2017-04-02, 12:49:16
Reply #20

Ondra

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This is again a problem of deciding what is diffuse (and should reflect the light) and what is reflection (and should not). Currently not easily fixable
Rendering is magic.How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2017-04-11, 23:37:53
Reply #21

Ondra

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cleaning this as I am moving all similar reports to our internal tracking system. We will give it a shot for 1.7
Rendering is magic.How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2018-03-06, 10:43:24
Reply #22

PastaJackal

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Hi, having the same issue using 1.7 hotfix 2. Any progress or work arounds on this at all?

We are constantly using backplates for our archviz images with a CoronaLightMtl and run into this issue frequently as a result.

Thanks!

2018-03-06, 10:59:51
Reply #23

Dionysios.TS

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It seems that the something similar happens in situation when sunlight goes through CoronaLightMtl, "emit light" unchecked.
Got this round shadow on glossy surface..

It seems like a behavior I got some days ago in an exterior scene where the sun was producing a big black spot on a surface.
I posted here in the forum the problem btw.

Dionysios -

2019-06-19, 10:24:07
Reply #24

mrsacan

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I don't think this resolved.. but ok.

2019-07-02, 11:54:34
Reply #25

maru

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I don't think this resolved.. but ok.
The issue itself is not resolved, you can read about it here: https://coronarenderer.freshdesk.com/support/solutions/articles/5000516180-known-bugs-and-limitations
But the thread/report is, as we already have it logged in our internal tracker.
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