Glass Reflection

[Infrared digital]

Hi

Usually when I want to have glass reflect the context, I would apply maps to planes and locate them at key points around the building to create good reflections but this can be time consuming.

So, I was wondering if anyone applied the reflections directly onto the glass geometry? This would allow for precise location of reflections.

In an attempt to do this, I have put a mix map in the reflection slot with 2 jpegs of the context mixed with the opacity map. The outcome is that it nearly works but the reflected building on the lower part of the glass lacks contrast.









If anyone has any ideas on how to make this better/more realistic - please let me know.

Regards

N

[tct70]

I add reflections in photoshop with a screen layer mode. You can then adjust its opacity for greater control. If you render a VrayMatID pass it makes slecting the glass very easy in Photoshop.

Trev

[Infrared digital]

Hi Trev

yeah, I'm aware of that method but would like to explore and see if it can be done mostly in Max as this would save alot of time and also, the building I am working on presently has alot of angles as opposed to just one plane of glazing.

[tricky]

If you render a VrayMatID pass it makes slecting the glass very easy in Photoshop.

Doesn't this create a very jagged edged selection?

[tct70]

Somewhat jagged yes.............but fine for creating a selection in Photoshop for reflections or colour adjustments etc.

[Infrared digital]

I think you have to assign red, green or blue colour to the geometry to get the MatID to select out correctly in PShop.

[tct70]

I just assign a number from the material ID channel in the Material editor and the colours are automatically assigned to the MatID pass.

[tricky]

But if you work with high res images, you need the AA to be sorted on the masks - only 100% red, 100% ble and 100% green will give you that accuracy.

MaterialID would be great, but I really don't think it is accurate enough. We recently did an animation where we used material IDs to re-colour certain geometry (just block colours) and the only way we could get it to work was to render the materialID passes at twice the resolution and scale them down to achieve reasonable AA.

[tct70]

Tricky,

I've had more success with the Vray Material Select element. AA seems to be significantly better.

[Paul Oblomov]

Use feather in post.