Glass in render or in post?!

[D C]

We work on large buildings, skycrapers with tons of glass! Often I'm not happy how well glass turns out in the render using correct material setup. We generally do high noon sunny day exteriors, sat within a park public realm area and the client would like to show this area receving lots of sunlight. This causes issues with glass on tall glassy buildings as this time of day such as the elevations on the facade not in direct light look too dark due to sun contrast.

I'm honestly just thinking I photoshop all of my glass instead now with 2d imagery in post so I have full control of it, and then I can fake it in and lighten things up a bit. The problem with this being it takes more time and may not produce ideal results by the end of it all.

How are you guy approaching glass on large projects?

 

 

 

 

[Francisco Penaloza]

Glass is a very subjective material, in my opinion.  Everyone has an idea or a concept how glass should react, but with all new render engines, glass work like glass. it reflect and refract depending on lighting and environment.

To get a rich reflective glass, you need a rich environment. If your building is very tall then it all depends on the camera angle and how many clouds are in your environment.

Having said that I always post process glass on still or animations. There is nothing wrong with that. Actually for me is as flexible as it gets. If you know what you want to get, then it should not take too long. If you need more flexibility, then you should render a few passes to help you in your post, Reflection, Refraction, Glossies. are typical passes for me to get the glass the clients want.

[Scott Schroeder]

I used to do glass as its own separate pass. So I'd have the exterior as one pass, the interiors as one pass, and the glass panels themselves as one pass. This gave me incredible flexibility, but the cost was the time to set it all up and deal with it when the project went into revision hell. For the most part, I've abandoned that workflow to do everything in one pass and only make minor adjustments to the glass in post. I've been fairly successful in getting clients on board with glass acting like real glass, so the nitpicking has slowed down quite a bit. I try to guide them in how best to show the glass from a camera view. An example is they tend to want aerial views looking down, which when the glass reflects all of the ground it tends to be somewhat dark looking. If you look at it from the ground up, you can get a much lighter looking glass as it is reflecting mostly sky.

Another method is to guide them into dusk scenes so the interiors glow more than they would during the day. With tools at our disposal like Forest and RailClone, populating interiors of large buildings is a snap.