Article: Good or bad paints - how to tell them apart, by guest author Hansrainer

Hello Jungle,

today we got an article ready for you by guest author Hansrainer.

Hansrainer is a long time follower of MV and friend of the jungle and he is particular always interested 
to look behind the curtains of paint, theories and practical questions when it comes to 
miniature painting. This article is not written by me, I am just posting it in the name of Hansrainer. 
Please keep this in mind.

Thank you Hansrainer for sharing your thoughts and ideas with the readers of MV.
Good paints or bad paints - how to tell them apart

Every now and then, I read people asking the question “can you recommend a good red” or something
similar on facebook or in forums. Maybe something like “is GW better or Vallejo?” as well.

With the same regularity, the apostles of one manufacturer or the other use this to advertise, 
why “their” paint manufacturer is best. But most of the time, when someone asks the question, 
what defines a good paint, it turns out that coverage is a main criterion, sometimes the price or 
the coarseness of the pigment used, the latter especially, when it comes to paints for airbrush.

Today I would like to dive into the peculiarities of paints, their different attributes, what causes 
those and then come to a conclusion how you find the best paints.

Pretty much all paints (bar few exceptions) 

consist of three basic components:

• Solvent medium
• Binder
• Pigment or Dye

The solvent medium

 is what makes and keeps the paint liquid - in the acrylic paints usually used by miniature painters, 
this is water. In oil paints (and enamel paints) it’s usually some kind of organic solvent like white spirit. 
As the solvent evaporates, the binder remains and starts forming a solid matrix in which the pigments 
are embedded.

The binder

 is the component that binds the pigment to the surface the paint is applied to by forming a solid layer 
the pigments are embedded in after the paint dried. In acrylic paints the binder is acrylic resin, a kind 
of plastic dispersed within the carrier (usually water).

In oil paints its linseed oil. A major factor controlled by the binder is the finish 
- usually the binder determines if the paints has a glossy, satin or matte finish.
The finish in turn does have an effect on how brilliant a paint appears 
(the same pigment will look way more desaturated with a matte finish compared to a satin 
or even glossy finish). 

The binder also determines the durability of a layer of paint against mechanical stresses 
a.k.a. rubbing off.

The ratio of carrier to binder (a.k.a.dilution) determines how fast or slow a paint dries and therefore 
how long it can be manipulated. This timespan is referred to as “open time”. 
While these two components don’t have a huge impact on how a paint looks, they do have when 
it comes to how a paint handles. (also, of course, this varies a lot between binders, acrylics have an 
open time between minutes and hours, oil paints can be open for months!)

You might think now “if I dilute my paint heavily, my brush ends up soaking wet” - 
that’s true, after all you just added a lot of water. 
But if you apply the same amount of paint, the diluted paint will dry faster than the undiluted paint.

Now, the most interesting part at first glance are the pigments. 

Most acrylic paints use solid pigments, the exceptions are probably most inks and glazes 
which are likely to use dyes. Dyes  actually solve in the solvent (like salt in water). 
Pigments are dispersed (think sand in water). Thats why some paints start to settle after 
a while and others don’t. For now, I will mostly talk about pigments, but dyes are in most ways similar.

Pigments are basically just really, really fine ground particles of a colored substance. 
Pretty much all pigments we will find in paints fall in to the category of nanoparticles and you 
won’t be able to discern them with the naked eye. At this point I would like to dispel a myth 
with regard to airbrush-colors: No hobby paint has pigments so coarse they would clog an airbrush. 
It’s not the pigment, its the binder. So, you can pretty much dilute any hobby-paint to make it go 
through an airbrush. Some paint might form clumps easier than others, but that’s not due to 
pigment size.

So, back to pigments. Since every pigment is its own chemical substance, 
they vary quite a bit with regard to transparency/translucency. 
That is the amount of light, that can pass through this material. 
Many colored pigments are actually translucent to some degree, 
which means they don’t cover very well. (In reality, this is a LOT more complex - 
and if you are interested in the physics behind it, I really recommend this article: 
https://www.naturalpigments.com/art-supply-education/transparent-opaque-paints/ )

_________________________________________________________________________

Now, if you buy artists paints,

you will usually get the information if the paints are opaque, semi- opaque, semi-translucent or 
translucent (its most of the time printed on the tube or you can just see for yourself 
- Golden Acrylics for example always paints a dab of the paint outside on the tube.

In most hobby-paints, that information is usually missing, 
with Warcolors being the only manufacturer that adds this information, to my knowledge. 

Since many hobby-painters equate strong coverage with good quality, many manufacturer 
add some opaque filler-pigments to the mix in order to increase opacity. 
Usually this is done by adding chalk or other white pigments. A similar effect can be achieved by adding
black or grey. However, this often leads to rather desaturated paints in the end. 

There are some amazing exceptions from this rule, most impressive among them may be 
Mephiston Red by Citadel. Here we have a brilliant red, that provides a great coverage. 
While I would really like to know what pigment mix they use, I honestly have no clue.

Now opacity is a boon if one aims to work with covering layer over covering layer. 
But for techniques that involve glazing or that build on previous layers of paint to shine through to 
define light and shadows, it’s rather annoying.

Often hobby-paints are composed of a mix of pigments, 
while artists colors often try to limit the pigments to a small a number as possible. 
Why is that? One thing is the cost of production: If you look at fine artists paints, 
you will soon notice that some paints cost considerably more than others. 
That is due to the scarcity of the used pigment. It is often possible to 
achieve a similar hue with a mixture of pigments to a much lower price. 
The tradeoff lies in the fact, that those mixes behave a lot less predictable when 
diluted strongly or mixed with lighter colors to brighten them up 
(thanks to Alfonso “Banshee” Giraldez for showing that to me).

Another effect doesn’t so much show during the painting but years after: 
Many natural pigments have a much higher lightfastness then their synthetic counterparts. 
Meaning, the paint will bleach less over time due to exposure to UV-radiation and other oxidizing agents.

So, now coming back to the question of best paint: 
There are many qualities a paint has: 
brilliance, finish, solvent, opacity, purity of pigment, lightfastness, durability and several others more, 
not the least: Price.

How do you determine the best paint for you?
Easy: Find out what you need. What do you want to do with it? Do you want to paint covering layers 
quickly, or do you want to create delicate glazes. Do you need a matte finish before anything else, 
or is durability important because the model is used in games and faces a lot of wear and tear? 
As in all things in life, the more you know, the better the questions you can ask and in the end,
the better the answers will be.

The best paint is the paint, that does best what you need it to do. 
Sometimes that’s GW, sometimes Vallejo or Scale75, sometimes a fine artist acrylic paint and 
sometimes even a watercolor or an oil paint. Stay open minded, 
play around, find out what suits your style of painting and what’s fun to paint with.

Disclaimer: I know I am merely skimming the surface here - there are literally books written on all 
aspects I am touching here.

With best wishes,

Hansrainer