Problem

Adjusting material translucency causes scene to render brighter.

Step to reproduce:
1. Render scene
    Note the current brightness level.
2. Open Material editor
3. Choose or modify a material with translucency > 0.
4. Adjust any material setting.
5. Render scene again.
    Notice brightness level increases.

Note:
- Reproducible in all rendering modes that calculate light.
- Material being adjusted does not need to be applied to elements in scene.
- Scene will get progressively brighter each time the material is accessed in the same session.
- Re-opening the file will correct the rendering, until the material is accessed.

Solution

Possible reasons:
- This might be caused by a corrupted User Preference file (UPF)
  Try to re-create a new clean user preferences file:

http://communities.bentley.com/products/microstation/w/microstation__wiki/8978.aspx

- Using Visualization enhancement on an uncertified version of MicroStation.

Solution:

Install 08.05.02.27 (which includes all visualization enhancements up to 08. 05.10.01) in a new folder.