Monday, January 17, 2011
Tutorial-how to grid your canvas-ratio formula
I prefer to use a grid method to transfer my drawing to canvas. I like having a guide-wire that compensates for my lapses in judgment. How many times do you start a figure drawing only to realize you need another sheet of paper to get the feet to fit on the page?
Why use a grid instead of a projector? I have found that the projector is best suited to those who already draw really well....which is odd, since it is a machine to do the drawing for you. Once you have your projected drawing, you must paint on top of it, and it covers up the drawing...you need to know how to draw well in order to keep track of your drawing in wet paint. I have also found that when I project I get lazy about watching for drawing errors. I assume that all is perfect and I don't have to do any problem solving.
I like to grid as it gives a simple guideline of where to place the large elements. I still focus energy on drawing all the particulars, and the designing of those particulars. I feel engaged and connected to what I am doing. Would I like to just start painting sans gridding? Sure, I wish I could start with an eye or an ear and just work my way out...but I am not there in my skill level. I believe you can train your eye through the grid method to see more spatially. Test yourself once and awhile and jump in without a grid...work from life frequently, where it's all about on-the-fly painting. Doing a multiple figure painting with buildings and perspective? Forget on-the-fly! Plan, plan, plan!
So, where to begin? The most important aspect of the grid method is your ratio formula. Your reference must absolutely be the exact ratio of your painting. It's easy if your reference is an 8x10 printout, and your canvas is 16x20...they are both 4:5 ratios (four parts of a number and five parts of a number i.e. four parts of 4=16, and five parts of four=20.)
However, if you know the size canvas you would like to paint, and you know your reference size, you can use a ratio to see if you need to crop in on your reference to make them match. Lets say I want to paint an 18x24 image. My printout is 8x10. These are not the same ratios. I will take the shortest side of the canvas (18) and put it over the longer side (24) Put the longer side of the reference on the bottom (10) and put the unknown variable on top. Multiply 18x10 and divide by 24. This gives you 7.5."
I need to cut one-half of an inch from my reference on the short side to make them the same proportions. If you have photoshop, this is easier, as you can crop an image using a set measurement, and it will remain in that proportion no matter what size you make it.
Lets say you are now good to go on your proportional reference. I always use a 16 "square" grid. I find the half way points of both the long and short sides and draw my first set of lines, making a plus or cross. Into each set of quadrants I divide in half once as well.
On and 18x24, I find the 12" mark on the long side, and the 6" and 18" marks. Divide your reference as the same, and you now have matching grids.
I place my reference in a clear plastic sleeve and use a sharpie to make the lines on it. I can keep the photo for later use when I am done with the grid, and don't want the lines anymore.
Transfer what you see in each "square" from the reference to the canvas. It sounds quite easy...but pay attention, it's also easy to over or underestimate what goes in each area.