Dispersion is a common optical phenomenon, especially with fast lenses. The 90mm f1.25 lens uses 4 sets of achromatic doublets to significantly improve chromatic aberration and resolving power, and achieve excellent image quality. Its high speed and unique depth-of-field aesthetics make this telephoto lens the first choice for portrait photographers. The angle of view is 27 degrees. It highlights the main body and avoids the suffocating feeling of space compression that super telephoto lenses cause. The extremely fast f/1.25 aperture provides remarkable control over depth of field for selective focus shooting, and is also advantageous for handheld shooting in difficult lighting conditions. The convenient reversible design lets you attach the hood in reverse for easy storage. With the extended lens end, it can protect the lens from moisture, wind and shock. The aperture ring is graduated with the right amount of resistance and detent, marking full apertures from f/1.25 to f/16.