Measuring Ca²⁺ or pH in microscopy is important because both are fundamental regulators of cellular activity. Calcium controls processes such as signaling, contraction, and secretion, while pH influences enzyme activity, metabolism, and organelle function. Imaging these parameters in real time reveals how cells dynamically respond to stimuli, stress, or drugs, providing key insights into physiology and disease mechanisms. Experiments of this kind require special microscopes and particular expertise in sample preparation.