AutoCAD Inventor :: Bitmap Differences In 2013?

When using a diamondplate bitmap (same one we have used for years), it looks like this:

However, when introduced into an idw or iam (in 2013), it turns darker, like this:

how to make this brighter outside of the ipt environment?

The brighter bitmap was acheived by going into the styles editor, and cranking up the brightness and the ambience:

We are using I2013; this style has been uploaded from 2012. In 2012 and before, this bitmap was as bright as the first caption.