Specularity and reflection will inhibit the transparency, But so will diffuse and ambient. Also lighting and camera angles. Here are some guide line I use when making materials: Value or Optic Channels: Ambient and Diffused, Added together never = over 100% Reflection and Transparency, Added together never = over 100% Reflection and Diffused, Added together never = over 100% ( with Refection and Diffused, take into consideration that Diffused is the primary value as opposed to ambient ) When using a texture window to drive a value channel enable Alpha Scaling ( option at the bottom of mapping modes ) With alpha scaling enable the slider will set how much alpha is used drive the channel, instead of it being automatic 100%.

Stephen Ray