Background image not rendering behind windows

[Anonymous]

I'm having a problem with my rendered images where the background image does not show behind transparent surfaces, as in the image below. I am using a custom scene, and the problem does not occur with 'Outdoor Daylight Medium', and possibly other scenes, but I don't know what settings to look at to get it to work the same. I didn't think I had changes that much between that scene and my custom one. Can anyone suggest how I can fix this? Thanks.

[Barry Kelly]

You will probably want to adjust the ray threshold and ray depth settings.
See this post for more info and links.

http://archicad-talk.graphisoft.com/viewtopic.php?t=49107

Barry.

[Anonymous]

Thanks Barry, I had come across that issue that other people have been having, and after you suggested it I tried playing with those settings, but that didn't fix the issue. Obviously I couldn't try every combination of numbers, but I tried adjusting Ray Threshold, Ray Depth and Reflection Depth individually between 0 and 100, and the main difference was windows either being black or clear.

I was also able to get the closer windows to be clear, and the far windows to be black, which suggests that when they show the blue behind them, it should actually be the background image, and that it is another problem that is causing the background image not to show. And the blue is actually the 'Sky Visibility' from the Environment Settings - as in, if I turned Sky Visibility on under 'Compositing', that would become the background for the whole render, and the windows would look the same as they do in the image above.

Actually, I've just narrowed it down a bit, because when I turn off Sky under Environment > Physical Sky in the render settings, the background image comes through as it should. That is what I did originally when I said the render worked correctly with the stock scenes, because I thought that was how you used a custom background image. Then I remembered the setting I needed was under Compositing.

So based on that, does anyone know what I could change to get the desired result? Obviously turning off Sky completely changes the lighting, so I don't want to do that.

[Anonymous]

Hi Ben,

I will ask one of our team member to give you a call and hi will provide you with some suggestions.
good news is, I have tested it in V19 and it works fine. (yes, it was an issue in the previous version)

FYI, our V19 official release date is on 27th July.

Cheers,

[Anonymous]

Thanks Kevin, that would be good.

[Anonymous]

Wow that would explain why I was having such a headache last year doing a pool rendering with sun-rays going throw the window and the pool surface and getting the background image to reflect on the pool was a nightmare!! I am going to test this in AC19 myself..... Hope it works...

GSAUS_Kevin wrote:
Hi Ben,

I will ask one of our team member to give you a call and hi will provide you with some suggestions.
good news is, I have tested it in V19 and it works fine. (yes, it was an issue in the previous version)

FYI, our V19 official release date is on 27th July.

Cheers,

[Anonymous]

One of our C4D guru found an option in the detailed setting to control this option. (regardless of AC versions)

Try turning off "Sky visibility" and "Sky Refraction" from C4D detailed setting.

See how it goes.

[Anonymous]

I have the same problem but I cannot obtain the background image. How do you do that? I used Outdoor Light Fast (OLF) but the background is stuck with OLF. I wanted to use my own background image but the alpha button is fade. Any idea? That would be great to know how you guys did that.

I just started using AC19, never used 18. Skipped from AC17.

[David Maudlin]

cadpg:

With the PhotoRendering Settings > Detailed Settings unchecked (this simplifies the dialog box), Environment > Sky Setup: None, and Background > Background: Image and Browse... for the image you want to use for the background. Changing from Physical Sky to None may change some lighting aspects of the rendering, so be prepared for further tweaking.

David

[Anonymous]

Thank you David for a great tip....

However, I still wanted the shading or shadow to be lighter. Too dominated and very dark if I used without physical Sky. What a bummer. I really like the OLF with the background image, not separate. MMM... It has to be a way around just like old AC17. That is what i always used.