You're welcome, I hope it's useful!

Thanks!

Thanks for your comment, I hope it helps!

You're welcome! I hope it's helpful

Great idea! Thanks for your comment

Thank you!

That's a great question. I like to think it simplifies things. With the more familiar 1/3 grid you want to place your area of interest where one of the horizontal and vertical lines intersect. With just one horizontal line and one vertical line all you have to do is make sure your area of interest is in one of the four squares. You'll find that this places the area of interest very close to the same place as the 1/3 grid. So, with fewer grid lines you get the same result. Another benefit is that you will become less dependent on grid lines in general. They can become a crutch if you rely on them too much.

Thank you for your comment. Without the grid it's harder for beginning artists to take accurate measurements. We look at an edge in our reference photo and in our mind we're thinking something like "this is one-half, or one-third from the edge of the viewfinder." Having an additional horizontal and vertical line in the middle helps make your measurements easier and more accurate. In this video I show the process of taking accurate measurements: kzfaq.info/get/bejne/nrhidZSqzdfdlqs.html I hope this helps. I plan on making a specific video about using the viewfinder when sketching in the real world.

Thanks!

​@@minnahumble2294 I think back to early math class working with grid paper, they would show us how to transfer shapes by scale with the grids square by square.