Have you experience some problem regarding your glass reflection. Here are some tips that greatly affect reflections and glossiness of our glass materials
1. First i create a scene ( hallway and entrance) with Aluminum Framed Glass Door, then create another glass wall on the opposite side. see sample image.
2. For glass materials, set initial settings and see the image
3. Now play on Refl Glossiness amount. The glossiness amount have a major impact on glass materials we are using
4. As you could see theimage has a black colored on the reflection, it was caused by the numbe of Maxdepth, on the above image, if you will count the number of reflection, we have just only one. Now change Maxdepth to 2
then to 5
then to 20
Here is on my sample image using the same glass material setup

Happy Reading
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Vray Glass reflections and Glossiness Tutorials
arch ronel k. pabico
rpadc2002@yahoo.com