Hello All, I am running some experiments using Particle Image Velocimetry and Laser Doppler Velocimetry techniques. There is a slight mismatch in the Refractive Index of the fluid and my model (Approximately 5% difference) which is creating some uncertainty in my measurements. I was wondering if anyone has any ideas as to how I would be able to quantify the uncertainty in my calculations knowing that the refractive index of the fluid (n1) and model (n2). For simplicity, the model I am using is a spherical shell with the fluid inside. If someone can direct me toward finding a solution, it would be appreciated.