Thank for the information. What is the reason that the camera lens gives the 35mm equivalent?
That's just for allowing you to do an "apples to apples" comparison when shopping.
Cameras have different physical sensor sizes. For example... if I put a 50mm lens on a "full frame" DSLR and take a photo, then move that SAME 50mm lens to an APS-C crop-frame DSLR camera, and take a photo of the same subject from the same location (without moving the camera), the resulting image will appear as though I've zoomed in.... some 50-60% closer, in fact.
So simply stating a lenses "true" focal length can result in wildly different results if you do not ALSO know the physical sensor size of the camera.
For examples of sensor sizes, see:
Digital Camera Sensor Sizes: How it Influences Your Photography
To help provide a common frame of reference for comparisons, lots of companies provide the "35mm equivalent" because it was the dominant camera type for so many years that it can be used for comparison purposes.
Your camera tells you that it has a 4.3-150mm zoom lens. But that wont give you any idea of what the images will look like because you don't know how big the sensor is. They could tell you how big the sensor is (and they do) but then you'd have to know how to do the math. Instead... they just tell you that "if this were a 35mm camera, then you'd need a zoom lens that goes from 24mm-840mm in order to have the same wide-angle to zoom magnification range."
You could then move on to some other camera and it might have a completely different lens. But if it doesn't have a sensor size identical to your SX30, then the lens size would be meaningless because you still wouldn't know roughly how much "wide angle" or "telephoto zoom" available. If, however, they ALSO state their "35mm equivalent"... well now you have a common frame of reference. Now you can do an apples to apples comparison and realize that camera 'b' has a lens that can do a bit more "wide angle" but maybe not as much "telephoto".
