Is the grain taken at the telephoto end of the camera (especially the telephoto camera) coarser than at the wide-angle end?

The image quality produced at the telephoto end of the camera is not necessarily worse than at the wide-angle end.

The so-called graininess is actually the noise caused by high sensitivity. Controlling ISO at the telephoto end is no more difficult than controlling it at the wide-angle end. As long as you control the iso within a reasonable range when shooting, such as manually setting the iso, or setting the iso to automatic, but reasonably control the upper limit... As long as the iso is within 1600, there will be no problem. At least it won't degrade the image quality.

As far as the camera itself is concerned, when designing the camera, especially the lens, the manufacturer attaches equal importance to the image quality at the wide-angle end and the telephoto end. Even more effort is put into controlling the image quality at the telephoto end (for telephoto cameras, the image quality at the telephoto end is particularly important. This is what consumers pay attention to. How dare manufacturers despise it!). Therefore, in theory, the image quality at the telephoto end of the camera will not be worse than at the wide-angle end.

Of course, in the actual shooting process, shooting at the telephoto end is indeed more difficult. Let’s not talk about the issue of anti-shake. Just to ensure a safe shutter, we need to set various parameters such as aperture and shutter reasonably; for example, we need better air quality when shooting, etc. (When taking a telephoto shot, the air quality is poor, If the purity is not high, the image quality will be greatly affected, and the photo will look gray). For the former, you need to improve your photography skills to solve it.

For the latter, both the photographer and the camera are powerless...the only option is to choose good weather to shoot...