[vtkusers] Why would my TIFF or BMP image look dark?

[Alex Lear]

I have used vtkTIFFReader (or vtkBMPReader) to read in an image and 
displayed it with vtkMapper2D and vtkActor2D.  The image is a line drawing 
with black background and white lines which show up good in photoshop and 
gimp.  In the vtkRenderWindow the white lines show up dark grey and hard to 
see.  I have messed with the actor properties and the little/big endian 
settings in the reader.

Does someone have some thoughts on why this might be happening or settings 
to try?

Thanks,
Alex