For previous info on this subject please read
Advice for Painters part I and II - Painting essentials, your pallet and painting meduims.

Advice for painters Part III

Transparent and Opaque Paints

Transparent = so sheer as to permit light to pass through. Stained glass and clear plastic are transparent.
Opaque = not transparent or translucent; impenetrable to light; not allowing light to pass through.

By mixing a medium like linseed oil and turps to any oil paint you can make it transparent, and you can then use it for glazing. However, certain colours of oil paint are designed to be used as glazes. These colours are very dark or almost black when neat (not thinned with a medium), colours like: Alizarin crimson, Olive green, and Phthalo blue. When you unscrew the lid of the paint and look into the tube it looks almost black, it only shows its true colour when thinned by a medium, and it's true colour will be vibrant and lustrous.

These colours can, of course, be used to mix neat with other colours, but it is important to know what they are capable of as transparent glazes. If you didn't know about transparent oils I encourage you to find the oil paints you already have that look dark when neat, and mix them with some linseed oil and turps to see their true colour.

Opaque paints pretty much look the same neat as they do thinned down; they are designed to be mixed with other colours for your 'fatter' layers in your painting. (For more info on fat/thin layers see using oil mediums in Advice for Painters part II)

Of course you can and should use opaque paints for glazes, but there might be a better transparent paint available to do the job better.


Glazing

Glazing is a process of painting involving laying thin translucent layers of paint on top of one another. To create a translucent layer mix a little oil paint with your chosen medium until it is thin enough to see through.

Each layer must be dry before you can paint the next, otherwise you will loosen the layer below and end up with a blotchy effect (it's a nice effect if you want to play with it, but it's unpredictable).

Imagine glazing like laying different colours of see-thru plastic over each other. If you took some see-thru blue plastic and laid it on white paper, it would still be blue, but lay a piece of yellow see-thru plastic over the blue on white, it would look green. Glazing in oils works in the same way, you lay different colours over each other to create colour.

Using this technique you can create many colours with a depth and lustrous quality that a simple wet mix of colours could not match.

Glazing is a tricky process to use because often you have to think 2 or three layers ahead and to understand the effects each colour has on another. It's still trial and error for me sometimes, but it is a technique that can produce the most amazing paintings.

One Deviant on this site who shows a great example of painting in glazes is ~cobainsriff these 6 photos show how he has build up the layers of glazes in his painting.


The Artist’s Handbook by Ray Smith has more photos of this process being used. I strongly advise anyone who wishes to understand glazing in more detail to take a look at this book.

There are many different ways of painting in Oils, this is just one way, my way and my way is mostly traditional. This advice is not set in stone; in fact I encourage any artist - however well established - to experiment constantly with new ways of working. I write this journal so that I can help those who are confused by oils or confused by painting figures, it is also for people who want to know how another artist works.

If anyone has further questions or has specific work they want me to critique, please leave them in the forum thread I have started on my page here: [link]