General reply, no, they are not. Specifically, what kind of grain, how is your process to enlarge. You have the color grain that can be erased as noise by several applications or with a system of filter layers in photoshop. But Luminance grain if reduced affect the sharpness of the image. Are you enlarging from classical process? the only way to reduce a bit the grain is make the prints with diffusion light enlargers. If you are scanning, depends of the scanner and software of the scan how to avoid grain and how well exposed and developed are your negatives. There are some scanners that have an inner unsharp mask that sometimes is too harsh. You can disable this function and then locally sharpen those images to avoid huge grain in clean spaces like skies.