Starting trait

Trait Name:Eye of the Hunter
Trait Tier:D
Trait Requirement:Ranger Class
Trait Description: Through training and hunting the user's eyes are better than normal.  
Trait Effect: The user is able to see speeds of even the fastest beast within the land, allowing the user to see speeds that would be normally blurring to others while granting a clearer sight to the user. This effect has a 10 meter range, everything outside of 10 meters is hazy, but still visible.

For a D-tier trait it's fine for the most part, but I don't think D-tier would be enough who are to fast to even comprehend like the flash step. As with this trait your eyes would only be slightly better than a normal humans and it would need to be higher to have stronger range, and use.

This traits only allows me a clear sight of A tier speeds, since you yourself said A tier speeds which are "blurry" to normal people yet you can still see them just not clearly.

This true, but there are some things which would be faster than what you can see. Afterall this is only a dtier trait, I'd give it a short range of 10m is how far you can see them clearly and anything beyond that is a little hazy but you can still make them out.

Edited