Quick tip for photography......tracing paper. Yup, use tracing paper as a "filter". It is what I use on my work lights when I want to take photos. The tracing paper kills the sharpness of the light so that you still get the brightness, but without the glare. The sheets may be too small as is for your needs, but use some clear tape to join together enough to make a sort of umbrella. If you angle the setup just right you should get exactly what you are looking for....good light without the glare.
Brian