ABC's Closeup documentary on mental illness, "They Have Souls Too," to be broadcast tonight at 8:30 on Channel 7, is rather more myopic than close.

It is also superficial and often irrelevant.

Much of the first part of the program deals with the horrors of insane asylums of two or three decades ago -- patients lobotomized, raped, or victims of insulin shock therapy and inept electroshock therapy.

Most of the rest of it deals with personal stories of the mentally ill on the streets of this country's large cities. This is indeed a serious problem -- an estimated one-third of the homeless are mentally ill, many of them deinstitutionalized in the mass exodus from mental hospitals of the '60s and '70s.

But nowhere in this Closeup do we hear more than cursory reference to attempts to remedy the situation. And only one physician, not identified as a psychiatrist but sounding like one, is quoted. Without doubt, the problem of the mentally ill on the streets is a nasty one, but this documentary purports to deal with mental illness in general, and after presenting its horror story of the homeless it just sort of clucks and pans away.

Even the upper-middle-class family with a son described as "suffering from a psychosis" (but who manifests a lot of symptoms of schizophrenia) seems to have had nothing but bad experiences with the mental health establishment. Yet more successful treatments and therapies exist for mental illness than ever before in the history of humanity.

Nor is the term "mental illness" ever broken down into its myriad parts -- depression, manic-depressive illness, schizophrenia, among others. Some of these -- especially the depressions, with or without cycles of mania -- are eminently treatable, usually with a combination of drugs and psychotherapy. Even electroshock therapy, relegated by this program to the horrors of the past, is newly respectable. New knowledge about the electricity of the brain, combined with high technology and more refined techniques, has made electroconvulsive therapy (ECT) a useful, often singularly successful tool in the hands of trained specialists.

Finally, there are a burgeoning number of support organizations for mentally ill patients and their families -- the National Alliance for the Mentally Ill is one -- and there has been a concerted effort on the part of psychiatrists and these organizations to strip away the lingering stigma attached to mental illness. ABC has done very little to aid these efforts. 'Evening at Pops'

Ultimately, your reaction to tonight's "Evening at Pops" program on PBS (Channel 26, 9 p.m.) may depend on how you feel about Norman Rockwell.

The program is not a single Boston Pops concert but an hour-long anthology of what someone considers the best moments from a whole series of concerts -- a cavalcade of stars featuring Andy Williams, Cleo Laine, Oscar Peterson, Ray Charles and Peter, Paul and Mary.

But Norman Rockwell, without singing a note, may have stolen the show from all of them, because television is much more his medium than theirs. For the average American, the visual pleasure of Andy Williams singing "Moon River" in close-up begins to fade after about 10 seconds. The joy of watching Cleo Laine sing "Turkish Delight" (to the tune of Mozart's "Turkish Rondo") may last a bit longer because she has interesting, expressive features and she is engaged in something challenging. But no singer -- not even Peter, Paul and Mary combined, gyrating through "This Land Is Your Land" with the audience singing and clapping along -- can match the visual impact of a camera panning slowly, tenderly over a series of Norman Rockwell paintings.

Rockwell comes in toward the end of the show, with composer-conductor John Williams leading a quick tour through the Norman Rockwell Museum in Stockbridge, Mass. Why this excursion from music into graphics? The answer becomes clear with the transition into the final number on the program: Rockwell will be used to illustrate Williams' inspirational song, "America -- And the Dream Goes On." It is a cleverly parasitical arrangement, except that Rockwell's technically clean and conceptually honest (if not particularly deep) visuals completely outclass the easy sentimentality of Williams' music. This is the second piece by Williams on the show. The other is from the sound track of "E.T." and sounds emptily repetitious without the visuals.

Otherwise, the show is good, notably in a splendidly imaginative "Body and Soul" by Peterson and an intense "Georgia on My Mind" by Charles. There are problems with this kind of show, but they reflect on the packagers, not the performers.

One problem is that a great orchestra spends much of the hour sitting and watching performances of music that has nothing to do with an orchestra, pops or otherwise. Another problem is that (unlike the programs of Arthur Fiedler in his pretelevision heyday), this concert gives listeners only the haziest idea that there might be worthwhile music older or more complex than "This Land Is Your Land." A third is that the medium and format focus attention on the performers' personalities rather than the music they are performing -- a distortion of artistic priorities.

Laine, Charles and Peterson are all well worth watching. But they do not really need the Boston Pops for accompaniment, and the Pops should be heard more in its own repertoire.