How to save image from picturebox using c#

Question

Hi,

i need help on how to save the image that return from picturebox?

basically the program works,
1)Read image (.png)--> load into pictureBox1
2)Fire button save to save the image from pictureBox1

Here i place code:

 using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace OpenSaveImage
{
    public partial class Form1 : Form
    {
        
        public Form1()
        {
            InitializeComponent();
        }

        Bitmap OriginalImage;

     
        private void btnOpen_Click(object sender, EventArgs e)
        {
            //Open File Dialog to load image files
            openFileDialog1.FileName = "";
            openFileDialog1.Title = "Images";

            //Filter the filedialog, so that it will show only the mentioned format images
            openFileDialog1.Filter = "PNG Image(*.png)|*.png|JPG Image(*.jpg)|*.jpg|BMP Image(*.bmp)|*.bmp";
            openFileDialog1.ShowDialog();

            if (openFileDialog1.FileName.ToString() != "")
            {
                pictureBox1.ImageLocation = openFileDialog1.FileName.ToString();
                OriginalImage = new Bitmap(openFileDialog1.FileName.ToString());
            }

            butSave.Enabled = true;
        }

       // private void butSave_Click(object sender, EventArgs e)
       // {
         //   SaveFileDialog saveFileDialog1 = new SaveFileDialog();
         //   saveFileDialog1.Filter = "PNG Image(*.png)";
         //   if (saveFileDialog1.ShowDialog() == DialogResult.OK)
         //   {
                //saveImg(saveFileDialog1.FileName, new Bitmap(OriginalImage), 85L);
         //   }
    //    }


        /*
         * Code for save image
         */
        
    


    }
}

hope someone could help me, thank you