How can I add reflections on glass using HDRI?

[leorobleto]

I have an outdoor scene of a small information booth. Made out of glass and concrete and wood.
I am using VraySUn and VRay Sky as my environment.
However, I want some reflections on the glass to improve "realism".
I used an HDRI image on the Reflections dialog under the Environment Tab (See Images).
When I rendered, the glass shows no reflections.
Is it my material or anyhting else I am doing wrong?

Thanks for the help

[leorobleto]

Re: How can I add reflections on glass using HDRI?

I tried uploading images but a message says "upload server is full".
Once its freed up Ill post them for your comments.
Thanks

[rmehta]

Re: How can I add reflections on glass using HDRI?

What angle are you looking at the glass at? If you're above the bldg looking down, you will only see the ground reflected. You must be a eye level or lower in order to see the sky reflected. Also, check the multiplier on the hdr image. when using the sun, i've found I need to use something like a 30,000 multiplier for the image show up. The easiest way to get this right that i've found, is to change the glass to chrome and render it to see what the reflections are doing. then when you have the multiplier/angle right, change back to glass.

[schultzeworks]

The trick with reflections

A flat area will only reflect a very tiny part of the background, so it usually looks like its not reflecting at all. To see exactly what is going on, I usually place a temporary chrome sphere in the scene. It works great as a guide to show you everything that is in the 180 degree hemisphere facing the camera. This will help you to then rotate the background -- or move the camera -- so the "interesting parts" of the reflection end up where you want them.

[schultzeworks]

Example of the test sphere

In this example, I used an HDRI background to add a little spice to the studio set for the products. You'll notice that in the flat areas of the black MP3 players, you see very little of the HDRI background -- while you get more on the corners and fillets. Of course, the chrome sphere is out-of-control and shows everything.