The phrase "a vague image of" is correct and usable in written English.
You can use it when describing something that is not clearly defined or is only partially understood.
Example: "As she spoke, I could only form a vague image of the place she was describing."
Alternatives: "an unclear picture of" or "a hazy impression of".
A vague image of what was later diagnosed as a super giant cerebral aneursym.
Until last week, most Americans familiar with Freddie Mac or Fannie Mae probably had a vague image of benevolent government agencies helping young couples get their first mortgages.
Those who still harbor a vague image of Robby Benson as a wholesome teenage heartthrob from films like "Ice Castles" may be surprised to find, during an odd sing-along moment in his new stage musical, that they are asked to belt out lyrics whose main component is the most vulgar of curse words.
Mulder's wilted office poster displayed a a vague image of a UFO with the bold, white text, "I want to believe".
When the name Sam Maloof came up twice in one day recently, I realized I didn't know much about him -- I had a vague image of a rocking chair in my mind.
Their bodies are limp and unresisting as they conjure vague images of social dancing to a collage of recorded waltzes.
I was like Emma Rouault before she became Madame Bovary, someone whose most intense life was in books, from which I had formed vague images of passion and adventure, love and weddings, marriage and children.
It brings to mind a vaguely Romantic image of solitary figures meandering along circuitous paths.
It allows for a vague and hazy image of war and its toll.
In return we cultivate a vague, almost occult image of artists and artistic production, characterized by long, moody walks and tormented bursts of inspiration.
In "Brother, Sister," the smoky tones are applied to a buccaneering, vaguely predatory image of exotic adventure in uncharted waters.
