Wednesday, February 12, 2014

What is paper sizing?


Watercolor paper is by far the most technically difficult paper to make which may be why no two brands of watercolor paper act the same. But that does  not mean to say that one type is better then another, what is “good” for one for one artist may be “bad” another. It all depends on a person’s technique and imagery. I would encourage everyone to try more than one manufacturers brand to see what the different qualities are.

There are 3 terms for gelatine sizing that all mean exactly the same thing:
1. Tub Sizing– because handmade paper is actually soaked in a tub of dilute gelatine and water,
2. Gelatine Sizing– because it is made of gelatine,
3. Surface Sizing–because it is applied to the surface of the paper.

Some manufacturers, like machine made Arches and handmade Twinrocker, surface size their paper with gelatine. Other manufacturers surface size with vegetable starch. All surface sizing helps to keep the paint from sinking into the fibers and becoming “muddy”. However, there are many technical factors that contribute to the way a watercolor paper performs.
What is sizing?
Gelatine sizing is a surface sizing of animal glue or gelatine. In Europe before paper was made, monks wrote on animal hides called parchment and vellum with quill pens. When paper began to be made in Europe in 1150 AD, people wanted the paper to act like parchment and not bleed with water base inks so they dipped the sheets in liquid parchment or hide glue. Today, along with surface sizings like gelatine and starch, papermakers also use modern internal sizing’s that can be added to the pulp itself. Most watercolor paper is both internally and externally sized.
What does sizing do?
Sizing effects the performance of the paper and how it takes the paint, it helps to resist scratching and lets the artist make the necessary changes and corrections when painting. Such as having the ability to lift and remove color. Without it, water and color would soak right in, making it an extremely difficult surface it would react more like a blotting paper or paper towel.

Tuesday, February 11, 2014

Tip: Old Paper

The other day I received a letter from one of my students, she was having a horrible time trying to do one of the exercises from my book "Watercolor Essentials"The problem was when she applied water and color to the paper it soaked right in.

I first asked her what brand of paper she was using, (that can make a HUGE difference). Student brands most often will not react the same as the professional grade papers (my personal preference has been 300 lb CP Arches paper and for exercises 140 lb). Student grade papers have a tendency to curl badly and blending color does not react the same way due to the surface.

I asked: how old her was the paper ?
Her reply: about 10 years old.

The problem is:  depending on how long and where the paper is stored, overtime the elements can  degrade the sizing on the surface (yes even though it is archival). Most likely you won't notice anything wrong until you apply water and color, then the big reveal happens. You start to see blotches and spots or even scratches. It's truly a shame, after you have spent good money for good paper and especially  frustrating if you have taken time to create an intricate sketch. Usually the fresher the paper, the better the results.

In my students case, the paper immediately soaked up the all water and color, acting more like a blotting paper or paper towel, making the technique ineffective. What you are looking for is the water and color to stay on the surface while your working and have the ability mingle giving that transparent watercolor look.


The exercise below can help you create a luminous washes and gives you better understanding of the feel and flow of water with color that I'm looking for.

140 lb Cold Press Arches Paper