Rendering objects (e.g. products) with 1. a pure white background and 2. a transparent background

[Soluna]

Hey

I´ve been working with vray for a couple of years now but one thing I still haven´t figured out is how to render out products in front of a pure white background (which was always requested by a company I worked for) or in front of a transparent background so that I can change the background later in post. I´ve tried many approaches I found in YouTube videos but I couldn´t really find a solution that works great for me. But since this is something that customers have already asked a couple of times I´d really love to know how this works.

I haven´t really worked with Blender a lot before but one thing I noticed is that there´s a tiny checkbox called "Transparent" with an additional option for "Transparent Glass" which works like magic! I attached a screenshot of a super basic glass object which I could render with pretty much 0 knowledge in Blender within maybe 2 minutes. Is this somehow possible in VRay? If not, is there any chance you can implement something like this? I´m pretty sure that many other VRay users (especially the ones that haven´t been working in the industry for a really long time) are struggling with this, too. Pure white backgrounds (or transparent backgrounds) are just really handy to have, whether it´s for commercial shots or for customers who´d like to have a higher flexibility in post or just in general for personal projects .

If this option already exists it´d be amazing if someone could help me with this. If not it might be a good addition to upcoming VRay versions?!

Thanks a lot in advance for your help!

Kind regards,

Soluna

[Joelaff]

You should be able to create a similar effect by enabling alpha for reflection and refraction in your material:

[Soluna]

Thanks a lot! That helped me a bit already. I exported the exact scene that I had in Blender to 3ds max. Same HDRI, standard VRay glass material but no matter what I try, the result is never rlly satisfying. I attached both results that I got right after rendering with no additional corrections. (I´ve tried playing around with the glass material values in VRay, too, but without any success).

[Joelaff]

Looks like the Blender glass is perhaps less transparent? Also I think it has reflect on backside turned on, some texture maps or procedurals for dirt and variance, and perhaps a better environment (lighting setup)

[Soluna]

So, after tweaking the materials and lighting a little bit I managed to get a result which is comparable to the one that I have in Blender . Thanks a lot already for your help!

The only thing I´d be interested in now is how VRay professionals handle transparent objects in general. Let´s say a customer wants you to create a product animation of a glass object (e.g. a vase) on a pure white background. Would you work with a white backdrop then? I noticed that when adding a backdrop the glass doesn´t look good anymore. So is there a way to add the white background maybe in post so that you can still keep the refractive glass look in the renderer? Or how would you approach that?

[Vizioen]

If you could show an example of what you are after we could direct you.

[Soluna]

This product on Amazon for example is on a pure white background. I think this one is cut out with Photoshop though since there´s no shadow or any kind of ground in general. But this is pretty much what I´d like to achieve. Background pure white with a product rendering of a glass, or (which would even better) a way to change the background completely in post. That way if my boss tells me that he suddenly wants a pure red background instead of white I could just do that in Photoshop without having to re-render it. I´m not really sure if that´d be possible because of the refraction of the glass. Not sure if and how I could simply change the background while still maintaining the correct refraction, etc.
https://www.amazon.de/Boule-Weingl%C.../dp/B06XWVSV73

I also attached 2 images that I rendered in Blender where I can now easily change the background with the internal compositing window.

[fixeighted]

Depending on the shape of the object and how it reflects, there's not one perfect setup. This image is
a stock Cosmos glass (minus liquid) with no ground plane, one plane light as a backlight and 2 invisible black cards
which are visible to refl/refr which add some definition. Shown with a white bkg.
So variations on that theme may be what you're after.

[Soluna]

I´ll have to try it out on the weekend Thanks a lot already for your help!