I believe some CCD cameras adjust the pixel gain automatically depending
on the overall image intensity.
Maybe you should check you camera settings?

Gareth

Vishwanath Somashekar wrote:

> The flow rates  in both cases are the same, the
> streams 1,2 and 3 are all dye solution of same concentration, the
> lighting condition remains the same. the exposure time remains the
> same. But why the change in intensity value?
>
> Has any one of you faced this problem? If so, can you suggest as to
> why this is happening.
>