A: Both are drum-based systems. The **5-Step system** offers more intermediate magnification levels, providing finer control and more options for viewing different depths or areas, while the **3-Step system** offers fewer, broader jumps in magnification, often preferred for its simplicity and robustness in standard procedures.

A: Coaxial illumination means the light source is aligned along the same path as the observation optics. This configuration effectively **eliminates shadows** within the deep surgical cavity (like the ear canal), ensuring the surgeon sees a consistently bright and fully illuminated operative field without obstruction.

A: Absolutely. Most models feature a **trinocular head** and beam splitter, allowing for the attachment of an observer tube or a video camera system. This setup is mandatory for surgical training, enabling students and residents to observe the procedure exactly as the primary surgeon sees it.

A: The **Green Filter** enhances the contrast of red structures (blood vessels), which is crucial for safety and precision. The **Yellow Filter** is sometimes used to improve visualization of specific tissues or to reduce glare when working with highly reflective surfaces in deep cavities.