What's the difference between acrylic and oil paint? Do you want to learn to paint but not know where to start?
Do you work fast, or slowly?
You can paint almost anything with acrylic paints!
Acrylic paints are one of the most important things you'll need when you start learning to paint; their fast drying and water-based nature make them perfect for beginners. Paper, card, canvas, walls, concrete, polystyrene, polymer, glass, wood, metal and many other surfaces — you can create whole new environments with acrylic paints!
You've set aside some time for yourself and decided to paint. You have a canvas ready, you've prepared your ground and you're ready to paint.
Everything is quiet and at peace with the world. You carefully squeeze out your paints, taking care not to use too much, and then what happens?
The phone rings.
Wrong number.
In that short time, the first blob of paint you squeezed out is already dry, solid and impossible to move. Scrape that blob off, squeeze out a bit more, ready to go, and…
This time it's the doorbell.
You put down your brushes, come back ten minutes later, and unfortunately everything has dried!
It's as though you never got the calm painting session you wanted.
The solution?
- Squeeze out more paint
- Add a drying retarder to keep the acrylics wet for longer (add no more than about 15% of the volume of paint, or the paint's structure breaks down)
- Use a stay-wet palette to keep the paints damp.
With oil paints the situation is different.
Because oil paints stay wet far longer than acrylics, they give you the freedom to start a painting and come back the next day to carry on where you left off. The paint on the palette will still be wet and workable; the colours on your canvas can still be blended together.
Because of the oil in oil paints (usually linseed oil), it's best to work on a prepared canvas or board. If you're going to prepare the canvas surface yourself, the preparation takes longer. Of course, you can buy a pre-primed canvas and start straight away.
Do you prefer subtle blends or hard edges?
The crisp edges you can get with acrylic paints can be very useful for painting more geometric subjects; you can mask off areas, work over them quickly, and easily cover a hard shape with thicker paint. Acrylic paints let you mix clean, bright colours very easily.
Blending with acrylics can be frustrating because of how fast the paint dries. If you're working on a large scale in particular, it can be almost impossible to work on the canvas as a whole to bring it together. You can achieve smooth blends with acrylics, but you have to work fast. You can add a medium to the paint to slow the drying and keep the working time open for longer.
Because of the slow-drying nature of oil paints, oils are the best choice if you want to create subtle blends.
Working wet is the surest way to achieve a soft transition in your painting. That's particularly true of portrait painting, where the subtle shading of a face may need constant revisiting and fine-tuning. You can also add slower-drying oils to your paints to create surfaces that stay wet for weeks.
Trying to create a crisp edge in oils without affecting the colours underneath means waiting until the next day, or until it's dry — otherwise your brushstroke drags the paint beneath and mixes with it. Because everything stays wet in oil paint and the colours mingle on the canvas, it's very easy to mix up "muddy colours".
Experience has taught me over time to work briefly and cleanly.
Colour shift in acrylics and oils
Acrylic paints are lightfast.
Predictive laboratory testing shows acrylics won't fade over time — the colours will look the same in 200 years as they do now. The binder in oil paint, the oil, yellows over time, which gives old master paintings that subtle glow; acrylics don't do that, because the binder — acrylic polymer — doesn't yellow. The most likely cause of fading is using pigments that aren't lightfast. That applies to both oils and acrylics.
If you add more acrylic polymer to the paint in the form of mediums (fast-drying mediums, flow-release mediums), the colour shift will be greater still. If you use student-quality paints with extra filler added, usually white, the colour shift will be more noticeable.
With oil paints there are no rapid colour changes.
Initially, oil paints stay the same colour when painted onto a canvas. However, once the colour dries, it can appear to change if the oil in the paint isn't fully dissolved into the canvas. That can cause some areas to be glossy (still holding oil within them) and others to stay matte (the oil has soaked into the layer beneath), producing a deader colour. To overcome this, you need to "oil out" the area of the painting you're working on. A paint surface can look dull, usually because of too little oil in the paint film as a result of absorption by the ground layer (or excessive use of thinners such as turpentine).
Professional tip: In classical painting, you build an oil painting in layers, and one of those layers is called the "dead colour layer". It's painted using oil paint thinned with turpentine over an absorbent gesso ground, which absorbs the oil, speeds up the drying time and gives the painting a local colour.
Oil paints take on a slightly yellow tint because of the colour of the oil (think of olive oil). Further yellowing occurs as the oil dries over time through the process of oxidation. The degree varies according to the binder used in the paint.
"Yellowing should therefore be seen as an unavoidable property of drying oils, and this should be borne in mind by users."
Professors Mallegol, Blaise Pascal University, France.
Do you prefer working with thick paint or thin layers?
Acrylic paints are among the flexible types of paint.
If you like the idea of using a palette knife and creating thick, impasto paintings, acrylics may be the choice for you. You can paint and build thickly, and the paint will dry. If you try to achieve the same with oil paint, the outer surface dries but the paint inside will still be wet.
Oil paints take a very long time to dry.
If you have plenty of time for your painting, oils may be better for you. You can work with thick paint, wait a few days for it to dry, then add thin glazes to build luminosity in your work. To work with thick paint you have to allow for the drying time of the oils. Each particular pigment needs a different amount of oil, which results in a different drying time.
Are you working in a small space?
If you're working in an enclosed space, acrylics can be a great alternative to oils. For acrylic paint you only need access to water, and acrylic paints have a very low odour compared with traditional oil thinners.
Ventilation is still recommended, since some acrylic brands contain trace amounts of ammonia (see Princeton University health and safety); this varies from brand to brand.
If you start working with oil paints in an enclosed space, the fumes from the thinners can overwhelm you — turpentine and white spirit can be really strong. White spirit can also irritate the skin, and turpentine rags can spontaneously combust!
Many new solvent-free gels are coming onto the market. These offer a way to thin oil paint without using traditional solvents. You can also clean your brushes with walnut oil. Odourless mineral spirit doesn't cut oil as well as turpentine and can cause problems if you use dammar varnish in your mixes.
Conclusion
Well!
Of course there's a huge variety of paints you can buy, but once you grasp which paint is best for your style, you can create masterpieces.
Which medium do you prefer, oil or acrylic? Let me know in the comments below.
Source: https://willkempartschool.com/what-is-the-difference-between-oils-vs-acrylic-paints/
