I've been having some difficulties getting visual contact on aircraft while merging; this is particularly problematic for me in actual missions where I always seem to merge completely blind because I can't seem to spot the incoming aircraft, even if I know their altitudes and approximate azimuth.
To demonstrate this, I made a custom mission. I've attached a full resolution (1440p) screenshot highlighting an Su-30 at 3.2 miles, which is clearly visible, and another screenshot at 2.4 miles, where I literally can't see anything. As reference, there is a second Su-30 a mile or so further back, which remains visible in both screenshots. As I continue to approach then I can start to make out the wings of the aircraft that I've got a lock on, but it seems to be more of a horizontal profile and very hard to see, especially if I don't know where it is. I'm not sure if others experience this or if it is purely related to my graphics settings?