Take Screenshot Before any ARCore model is rendered - unity3d

Question

I'm using Screenshot code to take a screenshot of the screen which is working fine but its also taking the arcore models with it. Is there a way to take a screenshot before models are rendered?
I tried to SetActive(false) then take a screenshot then SetActive(true), it does work but there's a noticeable difference i.e. model disappears than reappears.
Update: This is a script applied on ScreenShotCamera and it is updated after removing all the bugs (thanks to #Shingo), feel free to use it it's working properly
using GoogleARCore;
using OpenCVForUnitySample;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR;
[RequireComponent(typeof(Camera))]
public class SnapshotCamera : MonoBehaviour
{
Camera snapCam;
public UnityEngine.UI.Text text;
public RenderTexture mRenderTexture;
int resWidth=480;
int resHeight=800;
// Start is called before the first frame update
public void initialize(ARBackgroundRenderer background, Material material)
{
background = new ARBackgroundRenderer();
snapCam = GetComponent<Camera>();
background.backgroundMaterial = material;
background.camera = snapCam;
background.mode = ARRenderMode.MaterialAsBackground;
if (snapCam.targetTexture == null)
{
snapCam.targetTexture = new RenderTexture(resWidth, resHeight, 24);
}
else
{
snapCam.targetTexture.height = resHeight;
snapCam.targetTexture.width = resWidth;
//resHeight = snapCam.targetTexture.height;
//resWidth = snapCam.targetTexture.width;
}
background.camera.cullingMask = LayerMask.NameToLayer("Default");
//snapCam.CopyFrom(background.camera);
snapCam.gameObject.SetActive(false);
}
public void TakeSnapShot()
{
snapCam.gameObject.SetActive(true);
}
void LateUpdate()
{
if (snapCam.gameObject.activeInHierarchy)
{
snapCam.cullingMask = LayerMask.NameToLayer("Default");
if (ARCoreBackgroundRenderer.screenShot == null)
ARCoreBackgroundRenderer.screenShot = new Texture2D(resWidth, resHeight, TextureFormat.RGB24, false);
snapCam.Render();
RenderTexture.active = snapCam.targetTexture;
ARCoreBackgroundRenderer.screenShot.ReadPixels(new Rect(0, 0, resWidth, resHeight), 0, 0);
ARCoreBackgroundRenderer.screenShot.Apply();
snapCam.gameObject.SetActive(false);
HandPoseRecognition.captureTexture = false;
//string name = string.Format("{0}_Capture{1}_{2}.png", Application.productName, "{0}", System.DateTime.Now.ToString("yyyy-MM-dd_HH-mm-ss"));
//UnityEngine.Debug.Log("Permission result: " + NativeGallery.SaveImageToGallery(ARCoreBackgroundRenderer.screenShot, Application.productName + " Captures", name));
}
}
}
Perhaps I was a little ambiguous, what u mentioned in the comment has already been resolved thanks to you but the problem now is.
I'll show you the images:
These are the 2 cameras I have:
This is what my Main (ARCore Camera) shows
And this is what the (ScreenShot Camera) Shows

Answer 1

You can use layer, put every arcore models in one layer (eg. ARLAYER), then set camera's culling mask to avoid these models.
Pseudo code:
// Set models' layer
foreach (GameObject arcoreModel in arcoreModels)
arcoreModel.layer = ARLAYER;
// Set camera's culling mask
camera.cullingMask = ~(1 << ARLAYER);
camera.Render();
Create screenshot camera from another camera
var go = new GameObject("screenshotcamera");
// Copy transform
go.transform.position = mainCamera.transform.position.
...
// Copy camera
var screenshotcamera= go.AddComopnent<Camera>();
screenshotcamera.CopyFrom(mainCamera);
Update with your script
snapCam = GetComponent<Camera>();