Got a Real-World Weapon, Armour or Tactics Question? Mk. XXVIII

[AdAstra]

From my knowledge, the distance at which you can actually recognize what you see is highly dependent on what you're looking at/for. It's far from just comparing size and distance: something as simple as a person looking towards or away from you could change whether you notice them at all (people are really good at recognizing faces, and really human shapes in general). Is the object moving in relation to the background? What color is it? Does it have a clear silhouette? How does the visual "noise" in their vicinity compare to that of the object (i.e. cluttered terrain makes solid colors stand out and vice-versa)? These things are far more likely to shift the likelihood of perception than just distance, and should at least give advantage/disadvantage if enough of them are stacked up at once. One thing's for sure, don't just make an equation where say, size/distance x n = DC and call it a day, and the same would go for maximum distances.