Moderately desperate shadow catcher question

[pjano]

Hi,
I am usually good at trying to solve problems by googling and browsing tutorials but here I am stuck.
I am trying to learn how to integrate 3d objects into images. I know that a much more flexible and elegant solutions is to export
render layers and passes in order to have maximum flexibility in compositing bit I am trying to use the matte option in the common TAG of the shadow material for quick previews.
Nothing fancy, just to have a shadow from the object on the background image. But when I activate that option I am getting a weird result where the shadow is actually brighter than darker. Please don't mind the quality of light and shadows. It is just for quick testing. I did everything that most tutorials showed. (and actually there are not that many that show a integration of 3d objects into images or footage in the c4d/octane scenario) .
One of the tutorials that show that pretty well is:
https://www.youtube.com/watch?v=mST_-dmZYHc
I followed everything that was there in the first part. He is getting a regular dark shadow and I am getting a fain white shadow
Can anyone point me to a solution?
Thank You
Piotr

[jayroth2020]

The white color is caused by your default environment. Change that to black and it should look much better.

[pjano]

Thank You.
I changed the deafult enviroment color to black in Octane settings but I am still getting the same result.
piotr

[jayroth2020]

Do you want to post your scene so that we can take a peek?

[pjano]

yes! absolutely! Thank You so much for taking the time to look into it.
cheers
piotr

[jayroth2020]

Hi Piotr,

I have included a file that works. Several things:

1. The file you included had the environment color set to almost white (the default). I set that color to black. That setting is located in Live Viewer > Settings > Env. tab, default environment color. Normally, that recommendation would have worked, but in this case, it did not.

2. You were using the OctaneDayLight as your scene illumination, and that is why your shadow was white, as the type was set to Primary environment. When I set your Type to visible environment, with reflections and refractions enabled, the shadow disappeared.

3. I placed a targeted OctaneLight into the scene, and then the shadow effect worked.

4. I balanced out the lighting by changing the OctaneLight to spherical, and positioning the light above the cube object and to the right. In your background plate, the lighting is very overcast, so you would NOT have strong shadows in this case. By changing the light to spherical, it really softens the shadow. As is my habit, I changed the dropoff to Inverse Square, which is the most realistic. I also balanced out the size of the light to the power value of the light to get the illumination close. I also enabled the Use primitives option and the AI light option to get the benefit of the Spectron tech in Octane.

5. I added a material to the cube that would help to fit better in the scene.

6. I converted your background material to an Octane material, added an Octane Object tag to the Background object, and set up your scene so that the background will render properly in Picture Viewer.

I'll note that I was not aware that you could not use an OctaneDayLight with a shadow catcher, but the above steps remedy the issue.

Here is the resulting image:

Here is the scene:

testShadow_v001.rar

(111.82 KiB) Downloaded 122 times

[pjano]

Thank You so much!
You have saved me a lot of headache. I wasn't aware that the enviroment color was set to white although I thought I changed it. Also I always thought that any ligtht in the scene
cancels out the enviroment color. Interesting that the Octane Daylight is not working with a shadow catcher but I have to add that I am using the new Octane for mac so maybe not everything has been ported yet.
Thank You also for the addtional steps in integrating the object. I learned something extra.
Again, I really appeciate this
Thank You
Piotr

[ceen]

Is there a way to change the default white to black as default setup?

[jayroth2020]

You're welcome Piotr! Ceen, the reason that the environment color is set to near white is so that you see something in Live Viewer when you first start it up (assuming you have not set any lights yet). If the environment color were set to black as a default, then your whole scene would be black -- unless you have added a light source.

[ceen]

Thx, yes I understand that. But I always have a light setup in my scenes and find myself changing the environment like three times every day.