Tea, Anyone?

One thing I learned from this project is rendering glass in cycles can be very tricky.


lovely scene… love the atmosphere of it… feels like a nice old morning to me…

Very nice, maybe a little more exiting lighting would lift it further.

svenska bär :slight_smile:


everything looks perfect!

I would have used a cup like this one:


The one in the image isn’t quite tea-ish. The quality of render is great, tho.

I think the lighting is nice, and the thing that stands out to me is that you nailed the material on the metal can.

That glass is wrong. You have wrong the interface between glass and liquid.

This is correct (a quick search in google, not my image):

These are the three IORs and the way the normals must be in each of the three meshes:
(the way to calculate the IOR is: you take the IOR where the normal births and divide between the IOR of the material where the normal enters. For example for the green mesh it is 1.5/1 (1 is the air). For the blue mesh it is 1.3/1 (1 again is the air). but for the violet mesh it is 1.5/1.3=1.15

Note: Look that the liquid is only that blue line, it doesn’t have the violet mesh forming part of the liquid like you probably are using. it is simply a “circular planar surface” without volume.


Thank you everyone. I really appreciate your input.

@Bao2-- The liquid is sitting on top of the glass inside the cup. The liquid is actually hitting the side walls of the cup.

Here is a close ref pic I was looking at when I was modeling.


Yes, that is the problem. Bao2 is right. Both the glass and the liquid are calculated in IOR here, where in reality, there is only one refractive barrier…

But I really like it. Maybe a bit post work, some contrast as the glass is a tad washed out, but very nice. :slight_smile:

Edit: Wow. The image Bao2 posted was rendered in under 2 minutes. Using what? The Space Shuttle engines? The NSA Echelon backbone? Well, I’m exaggerating a little, but that’s fast… ;D

@Bao2 and Farmfield – I finally get what you mean. I will redo it. This is great. I’ve learned a bunch today. Thank you!

If that is a real image and not CG then that is not glass but some type of plastic. Glass doesn’t show the liquid floating inside like that. Look the image in post 7, you don’t see that liquid “floating” inside the glass but touching the exterior of the glass (because the distortion caused by the IOR).

That is a real glass. The company that makes them is called bodum. I have several of those glass cups that I use for drinking coffee and tea. The liquid is not floating. The glass gas an empty space, it’s quite cool how they make those. That way the outer wall doesn’t get hot.

You see that the bodum cup you posted is way more thick than the glass you rendered, so considering gas, etc. the IOR matter becomes even more complicated.
The original image is very nice, though, and, even if I don’t appreciate tea very much, I like the feeling it conveys. :slight_smile: