Oil paint mediums for my canvas?

Question

do people usually put a layer of a color over the canvas before they paint an oil painting? i think its called a medium. or can i just paint right away on the canvas?a

Answer 1

Hi Tony,

A medium is something that serves as a conection or binder.

For insteance a paint has the pigments and a binder/medium that binds the pigments together.

A medium in art, namely oil painting is also the mixing of linseed oil and turps (for insteance) that will be used to unify the different mixes.

Now, you don't mention if you have a raw canvas or an already prepared one (usually with an acrylic primer / gesso).

If it's already prepared, you can paint over it, however I like to apply more 2 or 3 coats of primer / gesso to make the surface smoother.

Some artists also like to apply a foundation white before advancing with the paint. I also do this, but usually add some pigment to tone the canvas. It all depends upon the work that I'm going to do.

This is something that you'll learn with time.

If you have any more doubts, don't hesitate to contact me. I'lll try to help you as best as I can.

Kind regards,

Joséhttp://www.hushcolours.com

Answer 2

If the canvas has already been sized and primd, then you can start painting.  

A medium is is often added to the paint.  Mediums can be linseed oil, turpentine, etc,,, each had their own use.  Generally, for a traditional painting, the rule is fat over lean, meaning the first layer of paint on the canvas should be paint diluted with turpentine/turpenoid called a wash.  

Answer 3

Sometimes I will use a light tinting color, like yellow, for a sunlit scene.  You can use other colors, but I usually prefer a plain canvas that has been primed with gesso.  

You can also use a product that stays wet for quite a while (Magic White) so you can paint wet-on-wet in the Bill Alexander or Bob Ross technique.

Answer 4

It depends on what kind of canvas you have.  If you bought a pre-stretched canvas at the store, it is already prepped and ready to go.  If you are planning to stretch you own, you need to prepare the surface by applying several coats of gesso before you paint.  

I recommend thinning the gesso slightly with water and applying it with a large flat sable brush all in one direction (vertical or horizontal) and then letting it dry for at least 6 hours.  When it's dry, do it again, but apply the gesso in the opposite direction (like brush it side to side on the second coat if you went up and down on the first one).  Do this 4 times and then let the gesso cure for an additional 24 hours before painting on it.

If you mean do you have to use an underpainting or tinting layer, then no, you don't have to.  Some artists will tint the entire canvas and others use underpainting layers (a rough painting that serves as a guide for building up the subsequent layers).  Other artists find the whole idea annoying and just use a charcoal sketch as a guide and build the painting one section at a time.

I don't tint my canvases, but I do use an underpainting layer.  I'm more fond of glazing to get an overall tonal effect.

Answer 5

If you paint on the canvas directly the paint will soak through the fabric. If you don't want this to happen you brush a few thin layers of something known as "size". (If you are a vegetarian you need to buy vegetarian size because size is made out of crushed rabbits bones.) Size is like a glue and as it dries it contracts the canvas and fills the tiny holes of the fabric allowing the surface to become taut.  The tautness helps the canvas to have a firm surface to paint on and enables the painter to press firmly onto the surface without causing dents. Let each layer of the size dry and then after the last one has dried you add what's called a "primer". Brush on each layer of primer thinly and let it dry each time.  Primer is usually white. You can use either an acrylic primer or oil primer if you are going to use oil paint. If you want what's called a "coloured ground" on which to paint your picture you can add a colour pigment at this priming stage or you can do a layer of your chosen pigment on top of the primer. The use of a mid colour for the ground can be used instead of white. It can be somewhere between white and black or between the lightest and the darkest of any colour you may choose from which to start your picture, the light colours of the picture are worked up to and the dark colours of the picture are worked down from this mid colour.

I recommend that you get an introductory book on it or go to an evening class to get the basics. It's great fun to do and there is a life time of learning ahead of you.  Learning the basics of painting is a great spring board for, as Julia Cameron says in her "Artist's Way" book, "discovering or recovering your creative process".