MIXED MEDIA : *** 1/2 “THE VALUE OF IGNORANCE” Sinead O’Connor, <i> PolyGram Music Video ($19.95)</i> : <i> Items in this periodic survey of pop-related books, videocassettes and laser discs are rated on a scale of one star (poor) to five (a classic).</i>

O’Connor and director John Maybury avoid the most obvious--and ignorant--approaches to filming music in this 35-minute video of a 1988 London concert. Nearly all camera angles are close-ups of her famous profile; though a backing band and crowd noise are heard, one fleeting look at the drummer is the only non-O’Connor shot. Sound static? Hardly. All sorts of colorful, abstract visual overlays add to and play with the black-and-white footage, somehow never distracting from the intimate tone the Irish singer strikes on stage; it remains baldly emotional. Johnny-come-lately fans take note: Seven of the eight songs come from her first album, not its current successor.