The phrase "a perceptive observer" is correct and usable in written English.
You can use it to describe someone who is highly observant and able to notice and understand things that are not immediately obvious.
Example: "As a perceptive observer of human behavior, she quickly picked up on the subtle tensions in the room."
Alternatives: "an astute observer" or "a keen observer."
Heilemann is a perceptive observer and a fine writer..
Along with being a perceptive observer of the human condition, he was a theatrical showman.
Chung is a perceptive observer, especially of her own inner life.
He is a perceptive observer of social behavior, but in "Two Thousand Years" there is more discussion than behavior.
Her richly detailed account presents a woman who was at once idealistic and elitist, fearless and vain, and a perceptive observer of society.
The answer, according to Alexis Madrigal, a perceptive observer of these things, lies in a decision made by the company's executives in 2009 to introduce a "retweet" button.
Trachtenberg is an extraordinarily perceptive observer of cats and persons, but to observe, after all, is never to truly know.
I grow a bit apprehensive too, recalling the words of an extraordinarily perceptive observer of Egypt's struggles in the past: "The edifice of despotic government totters to its fall.
"Fiedler comes across as a decent, bright and perceptive observer who admires the Met and is not entirely comfortable relating all the gossip she knows her readers are counting on," Anthony Tommasini wrote in The New York Times in 2001.
Fiedler comes across as a decent, bright and perceptive observer who admires the Met and is not entirely comfortable relating all the gossip she knows her readers are counting on.
As Israeli columnist Shmuel Rosner, a very centrist but perceptive observer of U.S. - Israeli relations, put it, if Obama "signaled that Israel could no longer take unconditional US support for granted, Mr. Netanyahu's domestic support would quickly evaporate".
