Truth is objective. It is unwavering and absolute. Imagine it as a straight line.
Perception is not unwavering. Perception constantly interprets that which is, wrongly or rightly, mis-perceives, wanders off in the wrong direction or hits upon the truth, at least once in a while.
Below is a graph of person A's perception, represented by the oscillating wave that intersects the horizontal 'truth' line, who perceives truth only so often. However, the oscillating wave is relatively close to the horizontal line, suggesting that person A's perception keeps a close relationship with truth.
Below is a graph of person B's perception, represented by the oscillating wave that intersects the horizontal 'truth' line, who perceives the truth more often than person B but is not omniscient nor completely aligned with truth either. And indeed, the oscillating wave is further removed in its wave pattern from the horizontal 'truth' line than person A, suggesting that person B's perception is further removed from truth generally but hits upon it completely more often.
The better in-formed you are, the more in line you are with factual truth, that which has occurred and is occurring, the more you are likely to be in line with philosophical truth, taking as it does its nourishment from factual reality and the more your perception will hit upon the truth exactly.
That being said, no one is God and no one has a complete grasp of the horizontal line. The most one can hope for is to intersect the horizontal line of truth on a more regular basis through self-introspection, self-information and self-wisdom (knowing what to do with what you know) and, equally, not veer from it too much as in the case of Person B through possible mis-information and a lack of discernment.