What is different of the 3D Obsidian ALR and the normally Obsidian ALR?

VIVIDSTORM always want to offer the best choice for different projector's request;

If your projector has low lumens, use a projector with a long throw or standard throw;
But want to watch the screen under low light conditions;

Because we have 3D Obsidian ALR and the normally Obsidian ALR screen material can be choice,it will make confuse when you purchase it before;

We suggest that you can choose the screen material that suits you through the video:

Summarize:
Please remember that there are falsely labeled lumens indicators on the market, so please refer to ANSI lumens as the standard reference value;

A: If the ANSI lumens of your projector is lower than 1800, we suggest you choose 1.2 gain 3D Obsidian ALR screen material

B: If the ANSI lumens of your projector is higher than 1800, we suggest you choose 0.8 gain the normally Obsidian ALR screen material