topic Re: Arnold | Mystery Blue Light in 3ds Max Shading, Lighting and Rendering Forum

Arnold | Mystery Blue Light

Anonymous — Fri, 31 Aug 2018 17:41:00 GMT

As I attempt to render some scenes, I have been encountering a problem in the form of a mysterious blue emission. Attached are a series of images to show the extent of the issue. Note, I've checked the emission values of all near by materials, and have eliminated the possibility of some mistaken value as being the source of the problem. The following are some characteristics that I've noted over time:

1). It grows. The problem started off as a couple of discolored pixels and, through iterations of renderings, has grown to the extent you see in the first attached image (1). The problem was actually larger (on the white of the door at the end of the hallway), which leads to the second point.

2). It can be 'deleted'. If the objects that are "infected" are deleted and re-imported, the issue occasionally disappears (in the case of the door). The remaining blue seen in the first attached image seems to be stubbornly sticking on.

3). It shows up in the following tested AOVs (all direct & indirect): diffuse, specular, sss, transmission. Attached is the PSD file (2), compressed and cropped from an EXR file. Note how it always shows up as a very saturated blue, regardless of the AOV.

4). It is in multiple locations. See the last attached image (3). One can identify the beginnings of this growing blue infection, highlighted with a red outlined box.

5). The commonality between all places where it appears seems to be that it is ON a specific material (a black, glossy acrylic). There are no blue lights in the scene (though there are magenta ones in one of the scenes).

6). If I move the "infected" object out of the scene, it carries this "infection" with it.

Wondering if anyone has encountered this. If so, and if you solved it, I'd greatly appreciate hearing about your solution. Alternatively, if any of you have ideas on how this can be resolved, I'd greatly appreciate some suggestions.

Thank you.

Re: Arnold | Mystery Blue Light

RGhost77 — Mon, 03 Sep 2018 04:08:53 GMT

I don't think that without scene we can found whats happens.

But, just guessing... maybe something in background color and some rays shoots in gaps between walls...

Re: Arnold | Mystery Blue Light

Anonymous — Tue, 04 Sep 2018 00:50:49 GMT

As in uploading the model may help diagnose the problem?

The issue is there's nothing in the scene that is as blue as this mysterious blue emission.

Re: Arnold | Mystery Blue Light

Stephen.Blair — Tue, 04 Sep 2018 18:37:23 GMT

Can you post a detailed Arnold log?

Blue is the color for NaN errors.

More experienced Arnold users are able to troubleshoot scenes.

Re: Arnold | Mystery Blue Light

Anonymous — Thu, 06 Sep 2018 11:18:54 GMT

That sounds great, I will get that log uploaded here as soon as I return from my travels (September 16).

Good to know that blue correlates to a specific error. Naming the monster is the first step to defeating it.

My apologies for the delayed response here (also a result of my travels).

Re: Arnold | Mystery Blue Light

Anonymous — Tue, 18 Sep 2018 14:22:16 GMT

Hello,

Following up on this, as I am back from my trip. Attached is a Render Log, let me know if this is what was sought out. If not, please advise on how I can retrieve the desired detailed log.

Thank you again for your help.

Best,

Mako