This might work for you
private void ButtonTest_Click(object sender, EventArgs e)
{
using (Graphics g = pictureBox.CreateGraphics())
{
g.Clear(Color.Transparent);
float ticksPerSide = 7;
float tickLength = 20;
float horzSeperation = pictureBox.Width / ticksPerSide;
float vertSeperation = pictureBox.Height / ticksPerSide;
Image image = Image.FromFile("c:\\temp\\image.jpg");
g.DrawImage(image, new RectangleF(0, 0, pictureBox.Width, pictureBox.Height));
Pen p = new Pen(Color.Red, 2.0f);
for (int n = 0; n <= ticksPerSide; n++)
{
g.DrawLine(p, n * horzSeperation, 0, n * horzSeperation, tickLength);
g.DrawLine(p, n * horzSeperation, pictureBox.Height, n * horzSeperation, pictureBox.Height - tickLength);
g.DrawLine(p, 0, n * vertSeperation, tickLength, n * vertSeperation);
g.DrawLine(p, pictureBox.Width - tickLength, n * vertSeperation, pictureBox.Width, n * vertSeperation);
}
g.DrawLine(p, pictureBox.Width / 2, 0, pictureBox.Width / 2, pictureBox.Height);
g.DrawLine(p, 0, pictureBox.Height / 2, pictureBox.Width, pictureBox.Height / 2);
}
}