Canon Lens Hood LH-DC70 for Canon PowerShot G1 X Digital Camera
Lens hoods are primarily designed to prevent unwanted stray light  from entering by extending and shading the end of the lens, ensuring no  problems with vignetting or motor functions. Additionally, since the end  of the lens is extended, you also get the added benefit of some extra  protection from accidental impact. Lens hoods match the specific focal  length of the lens it was designed for.