How to solve the dual camera, dual scene post rendering use EffectComposer

in my case:

let camera = new PerspectiveCamera( fieldOfView, aspectRatio, nearPlane, farPlane );
let cameraOrtho = new OrthographicCamera( -width / 2, width / 2, height / 2, -height / 2, 1, 10 );

let scene = new Scene();
let sceneOrtho = new Scene()

Both scene and camera will be rendered to rendeder at the same time.
Now I want to add post rendering to the first scene,But when I did this, the second scene in the scene disappeared。
like this:

 if(this.composer) {
            this.renderer.render( this.scene, );
    this.renderer.render( this.sceneOrtho, this.cameraOrtho );

what should I do?

Since you are performing multiple renderings for a single frame, you have to set renderer.autoClear to false. At the beginning of your render() function, call renderer.clear() manually. This approach is used in the official examples multiple times, e.g. in webgl_camera.