[vtkusers] "Flickering" in 2D images

[luis.uriarte at philips.com]

Hello vtker´s

I´m using vtkWin32OpenGLImageWindow to display 2D medical images in Win95 using VC++ 6.0 and VTK 3.1.2. I have no problem displaying them but when I change the grayscale I have an annoying effect. The window first goes black and after a short instant the 
new image is displayed. This really bothers when you try to change the grayscale in a continuous way, because it makes some kind of flickering on the window.
I have played with the Erase and DoubleBuffer attributes with no positive results.
Can anybody give a hint on what I´m missing?
Thanks a lot

Luis.