Strange Glass Reflectivity in Wine Bottle Scene

Question

I am testing out some materials and put together a simple wine scene from some downloaded assets.

This is the render:

Anyway, there are parts of the render that look pretty unnatural. I've pointed them out here:

1. The wine glass bottoms are unnaturally reflective. They almost look like metal.
2. There is some weirdness happening with the wine glass on the left.
3. There is a lot of noise only in the wine bottle side where it is reflecting the wine glasses.

Example of the noisy reflections I'm talking about (this is even after Optix):

Here's the glass shader I'm using for the glasses:

Here is my render setup and light paths:

I've deliberately cranked the Gloss, Transparency, and Transmission values to 32 after watching a talk about rendering glass accurately here. I've deliberately disabled caustics because well, cycles sucks at them.

Anyway, my questions:

1. How can I fix the unnatural reflections in the bottom of the wine glasses?
2. How can I denoise the reflections on the sides of the wine bottles?

Thanks for reading and for any assistance!

Edit:

Here is the blend file. I had to go with Dropbox because the file was too big for Blend-Exchange. Feel free to tinker with it and optimize anything.

Answer 1

A few comments:

• The bottom of the glass is flat, making a horrible thick mass of glass. Most glasses are concave like this:

• Use more samples for the render and less for the preview (to keep the interface more responsive and get better quality renders)

• Use more light bounces

• Turn Off ambient occlusion. In cycles you don't need it.

• To have less fireflies bring down the indirect light clamping. Most fireflies come from indirect sources.

• In my opinion the shader you are using doesn't improve the results of a regular glass shader.

• Don't use overlapping geometry, it will only yield problems, like Z-figthing, where the depth buffer will have a hard time differentiating faces that are close together.

Same thing with the labels, for very thin paper it is easier to work the materials part of the bottle and not as separate objects.

As for the lighting:

It is hard (I would dare to say that is impossible) that you will find an HDR environment that suits the scene perfectly, as lighting glass and highly reflective objects is an advanced task that requires careful planing of the reflected objects on the scene. Remember that you are not lighting the scene, but creating the reflections that will bring out the qualities of the objects depicted (reflectivity, opacity, transparency, shape, volume, roundness, etc).

How can I render objects with very shiny surfaces?

Take the advice from that link, and you disconnect the environment and start trying a single light source at the time. Make a single very big area light and play with it so that you understand what it does, how it is reflected on the objects and how the shapes are revealed,

Once you find a suitable placement for it, and only then, add a second one and evaluate the results until you are happy. Bring in only as many lights as you need for the effect you are after. The more sources you bring in the more shadows and reflections you will have to control, so be judicious and spartan when it comes to lights.

Use also black elements to create dark reflections among the bright sources.

There are countless articles on the internet on how to light and photograph wine, glass and shiny objects. Do your homework and learn from those who charge a fortune to do that (and don't forget to have fun doing it).