Yes, it's nearing a necessity for many situations:
* Video Recording: IS is *almost* essential for handheld video. Without it, your footage can look shaky and unprofessional, especially when walking, moving, or even just holding the camera for extended periods. Even "cinematic" wobble needs to be controlled.
* Low-Light Photography: IS allows you to use slower shutter speeds without blurring the image due to camera shake. This is critical in low-light situations where you don't want to crank up the ISO (which introduces noise) or use flash (which can be unflattering).
* Long Zoom Lenses: The longer the focal length of your lens, the more magnified any camera shake becomes. IS is incredibly helpful for getting sharp images with telephoto lenses, especially when shooting handheld. Think wildlife, sports, or even distant landscapes.
* Smaller Sensors (Smartphones/Compact Cameras): The smaller the sensor, the more noticeable camera shake becomes. While software stabilization has improved dramatically, optical image stabilization still offers a significant advantage in many cases, particularly in video.
* Casual Photography: For everyday snapshots, especially with your phone, IS is invaluable. It allows you to get clearer pictures in various lighting conditions without having to worry too much about perfect technique.
No, it's not *always* a necessity:
* Tripod Usage: If you primarily use a tripod, image stabilization is redundant. The tripod already eliminates camera shake. You can even disable IS when using a tripod, as it can sometimes interfere with stability.
* Bright Light & Fast Shutter Speeds: In bright daylight or when using fast shutter speeds (1/250th of a second or faster), camera shake is less of a problem. You can often get away without IS in these situations.
* Studio Photography: In a controlled studio environment with controlled lighting and subjects, IS is less critical.
* Certain Creative Effects: Sometimes, intentional motion blur is desired (e.g., panning shots of moving vehicles). In these cases, IS would work against your creative goals.
* Specific Lenses: Some older, very high-quality prime lenses (especially wide-angle lenses) can be used without IS in many situations due to their inherent sharpness and wider field of view. Also, some photographers are very skilled at bracing themselves and holding a camera steady.
Alternatives to Image Stabilization:
* Good Technique: Learning proper camera holding techniques (bracing, breathing control) can significantly reduce camera shake.
* Faster Lenses: Lenses with wider apertures (e.g., f/1.8, f/2.8) allow you to use faster shutter speeds in low light, minimizing the need for IS.
* Increasing ISO: While it can introduce noise, increasing ISO can allow for faster shutter speeds. Modern cameras handle high ISO much better than older models.
* Tripod/Monopod: As mentioned above, these provide a stable platform.
Conclusion:
For the vast majority of photographers and videographers, especially those who shoot handheld, image stabilization is incredibly beneficial and often crucial for achieving sharp, stable results. It reduces the need for perfect technique and expands your shooting possibilities in challenging conditions.
While not *always* a necessity, it's a feature that greatly enhances the versatility and usability of a camera system. If you're buying a new camera or lens, prioritize IS unless you have very specific needs where it's not relevant. Consider it a very important and common feature, especially given how well it works in current technology.