Real looking glass (yes, again)

[beestee]

Why look at renderings as examples without context of what you are expecting to see? Here are some photos for reference in comparison:

Storefront glazing

The biggest difference I notice is that nobody would typically take the time to model and place believable surroundings when the only purpose is to make the reflections in the glass more believable...but it has been done many times and there are many examples that prove this.

One of the shortcuts that many professional visualizers make is to only model what you would see, but what most of us do not account for is what would be seen behind the camera and only seen in the reflections.

[Sawyer]

Now beestee what you posted is not what is being worked on in max. What I see in those images is colored glass not just a flat plane. I do find glass hit and miss often I think its because I have imported files from Revit or Cad and the modeling is funky. Often architectural glass has a tint and colored edges. And some surface tension bump something. And I do agree that glass can kill a rendering but I dont see those maxwell images as looking that different.

[Lupaz]

Check out this image.
http://www.cgarchitect.com/content/p...p/image005.jpg

You can't say the guy has a lot of experience. It's done in sketchup and maxwell.
And yet, look at the glass on the right. That looks like real glass. Don't you agree?

And you can't say that this person is doing something that we aren't with vray.
I mean, it's sketchup for crying out loud.

[Sawyer]

And then you are saying that you think vray cant do this level? I would like to see a real world example - where you take a model render it out and see what you think the outcome should be then lets look at that otherwise we are just comparing oranges to apples. Something more than a glass plane in a sky.

So for spit and giggles I put this together, nothing fancy some greeble and an hdr.

[Lupaz]

For the record, I never said that I think vray can't do this. It's just that it seems that with maxwell it comes out much easier. I also said that I, and I emphasize "I", can't get to good glass easily, and many people using vray (including 10 professional renderers in my office) had and have the same problem.
That's why I was asking chaos group if they have a clue of why maxwell gets those results, IF they see any difference I guess.

[flino2004]

Lupaz.... I think we all have different standards for what is good and realistic..... The examples that you posted are way far from being photorealistic ones but you are happy with the glass. Glass is not difficult to get it acceptable good for common eyes.

[PIXELBOX_SRO]

Lupaz,
just read the whole thread and i think youre sufferign from "imprint".
You fell in love with Maxwell glass and from now on you will always compare it with everything else.
If you were shown 2 images done in vray, one with slightly better glass and one with "normal" glass and someone told you the "better" one (although slightly noisy) is done in maxwell, youll say you like it.
Get rid of this imprint and set yourself free.

None of the images you showed and said have great glass look nice (well at least the glass there)...or lets be more correct...there is nothing special about it.

1st of all you cant expect to have a perfect glass if you drop in a glass pane and HDRI...it will never look AMAZING.

If i were u i would try this simple setup:
Pure black diffuse
Pure white reflect
Fresnel checked and set to something around 2
Use realworld IOR value
Set reflection cutoff to 0 or 0.001
Use some colored fog so you get some nice colored edges. Only tiny amount though.
Use reflect on both sides option
Set the Reflection and refraction bounces at least to 10

and most importantly, use all this in a scene where there is something to reflect, not just a sky. HDRIs usually are not that good to make nice sharp reflections...even those 16000px ones.

No offence, just trying to help.

M

[samuel_bubat]

May be the fresnel curve that vray uses is not accurate?

That´s nonesense.. the range of your hdrs propabely are not correct. You can find hdrs with a range of 5 and hdrs with a range of more than 1000.
It´s not about the render engine but about the missing background knowledge.. sorry. A fresnel surface looked at from the front has a very very low reflectivity
but it has reflectivity. This is important ! Now when you have a sun from an hdr reflecting with a range of ~5 will look dull. Having a much higher range will make
the sun reflect while nothing else is reflected. Now it ´s all about the artist to get a balance between highlight and environment reflection. That´s why i never ever
use HDRs for flat windows. Also because the resolution is usually much to low when spherical mapped even when the hdr is 20k and larger. They are nice for cars
and rounded surfaces but not for windows. You can for example just take a gradient and adjust the range by adjusting the rgb multiplier from the map output to
get the desired range to make it hdr (hdr doesn´t mean it must be an hdr image just means values higher than 1 or 255). This may vary as your exposure or materials may vary. It ´s all about the artist not the render engine. because keep in mind physical correct rendering is a myth.
You can have a physical correct light distribution and physical correct reflections but you can´t have physical correct ranges nor can you have physical correct textures. Why can´t you have correct textures ? Question ! at wich lighting, exposure using wich camera do you photograph a texture to make it physical correct ?
You can´t, they´re all as correct as they are incorrect.
Why can´t you have a correct range ? As an example the Vray sun. It currently has a range of roughly 70 when set to noon. Now imagine having a monitor
that can be as bright as a real sun. Than you of course would need a range of 1. Because white would be the exact intensity as the real sun. So as an artist
you always need to keep this in mind. Take a close look at glass in the realworld. A common phenomenon when looking at windowed glas that reflects trees.
Where the trees are "reflected" you can see through the glas. Because the are much to dark to "trigger" reflections on a fresnel surface. The sky behind the trees
on the other hand is much brighter wich causes a reflections and you won´t be able to see through the glas in this areas.
here is a good example.
http://www.flickr.com/photos/marlowpics/2665324804/
Now imagine recreating this window in 3D. In case your HDRI has a to low range, most people would increase the reflection or adjust the ior to make the sky reflect
more. But than more reflection would also happen in areas where this wouldn´t happen in realworld. If your HDRI has a much to high range you would need to
decrease the reflection wich would result in nearly no reflection in other areas making it unrealistic as well. So it´s really all about the artist to go look in realworld
for a desired effect and being able to adjust the right parameters.

[grantwarwick]

The amount of times I've face palmed at Lupaz in this thread, hilarious.
Are you trolling mate?

[Pixelcon]

If posting a link to Peter Guthrie's work doesn't put an end to this thread, what will?
http://www.peterguthrie.net/

Look. Be in Awe. Take note that he uses very little post production. This is Peter using detailed environment, quality HDRIs and physically plausible shaders.

Enough said!?

Your examples don't even come close to his Allandale House series.

[grantwarwick]

If posting a link to Peter Guthrie's work doesn't put an end to this thread, what will?
http://www.peterguthrie.net/

Look. Be in Awe. Take note that he uses very little post production. This is Peter using detailed environment, quality HDRIs and physically plausible shaders.

Enough said!?

Your examples don't even come close to his Allandale House series.

There is a lot of post work on some of those images :P

[squintnic]

what a terrible thread lol
lupaz is all thats wrong with 'arch vis' IMO (no offence mate)

the black, 1.57 IOR, fresnel and *almost* full refraction with some fog perhaps for edge colour is the basic formula....
after that is environment, extra glass shader details such as bump/distortion, perhaps a vray blend if doing coated glass

i reckon more experimenting, more observing real world, more looking at photos (not renders) and less talking is going to go along way to solving this problem.

[Pixelcon]

He really doesn't use much. He uses lightroom for a photographic approach to post work. Very little to no matte work/passed based work/selection based adjustments).

There is a lot of post work on some of those images :P

[grantwarwick]

I tell people the same thing sometimes, trade secrets, ego, sometimes just can't be fucked dealing with the "how to" questions.
The fact is, color wise, you can do drastic changes with "little work"

[Neilg]

I get what he meant by little work - there's a large color change, but there isnt a folder filled with 100 adjustment layers with masks for every object in the scene with photography pasted over. The feels and colors are different but it's been pushed around as a whole.

More power to him, but we still render with no glass and build it all up in post. all about that super fine control and bending the truth.