How to Enlarge Images For Watercolors, Drawings, Or Paintings Using a Grid

When you do art for fun or for profit, it is inevitable that you will come across an image you need to enlarge. Maybe you took an extremely good picture of a landscape, or a friend or client has a photo in e-mail that they want you to paint. When that happens, you will need to be able to fit it to the “canvas.” Whether you are painting a mural on the side of a two story building, or just a pencil drawing on typing paper, here is a pretty simple way to do it.

If the canvas you are going to be working on is of a manageable size, the easiest thing to do would be to draw a grid. If you think of a map, imagine all of the horizontal and vertical lines. Usually, they are labeled with numbers and letters so that you can reference specific “squares” in that map. If you look at a map, you can see that the cities, landmarks and coastlines fall into specific sections of the grid.

You can use that same system to copy a drawing of any size. Photocopy or scan the original image, then draw a grid on top or create an overlay with a transparency. This is especially easy with today’s technology where you can simply scan the image and open it in any of a number of “image editors” such as Adobe Photoshop, Corel Draw, or even MS Paint. You can then print the image with the grid in place.

Next, draw a grid to scale on the “canvas” of your choosing. For instance, paper if you are drawing in a sketchbook, or on a wall if you are creating a mural. Draw your grid with a very soft pencil or very light paint so that it can be erased or painted over when you are done. If you are using a lighter weight paper, less than 100# weight, you can draw a grid in dark ink on a page underneath. Then clamp the pages together so that you can see the grid through the paper. That way, when you are done, you simply pull the gridded page out and there is no need to erase. The biggest benefit of this method is that the grid is reusable. If you create the grid on a transparency, you can even project it onto a wall with an overhead projector.

Once you have the grid, simply transfer the major features onto the your new surface. Just like looking for major cities or landmarks on a map, look for landmarks in your image. The corner of an eye, the bottom of an earlobe, and even the crease in a dimple can all serve to help place the image in the proper size and composition for your painting.

Lightly sketch in all of the major features and landmarks. You will also want to rough in your value map or placement of all of the shadows, lights and darks in your image. Then remove your grid. If you drew it in place with pencil, carefully erase the lines making sure to not disturb your landmarks or smudge your paper. If you painted them in on a larger project, simply paint over them.