There are many types of sketchpad out there and it can be very daunting as a beginner to understand the differences. I am going to explain the different sorts and what they are for:
Sketchpads for Drawing
Cartridge paper is a high quality drawing paper used for drawing and sketching and this is the type of paper in all drawing sketchpads. The paper will differ in weight (how thick the paper is) depending on the sketchpad. The general rule is that the more expensive sketchpads will contain thicker (higher gsm) and better quality paper. I recommend 200 gsm or more for the better quality paper. The other thing that may differ is the texture of the paper, most sketchpads contain smooth cartridge paper but a few are textured with a fine grain. Both textures are fine for drawing so it is just a personal choice.
Watercolour paper is thick, usually textured and extremely absorbent. It has a high cotton content which makes it absorbent to very diluted paint (washes). Watercolour painting usually involves washes therefore a very absorbent paper is needed so the paper won’t buckle and this paper dries quicker. Good quality watercolour paper is very durable and can cope with multiple washes. It can also be very expensive (over £5.00 a sheet), the top quality watercolour paper is often more economical to buy in a sketchpad form rather than in individual sheets.
Do not skimp on the cost because of all the media, watercolour is one where you can’t really cut corners with the paper. Thinner, more wood-based paper will turn into pulp under many washes and will buckle and become unworkable.
The texture of watercolour paper can vary, some are very grained known as ‘rough’ paper and some are smoother know as ‘hot-pressed’ and ‘cold-pressed’. The texture is a personal choice but generally artists who want to achieve lots of detail and texture choose hot-pressed watercolour – it is good for very detailed botanical illustrations. Rough is usually used by watercolour artists who work in a looser style with lots of washes.
There are artists who use watercolour paper for coloured pencil work just because they like the quality of the paper. This is fine but you would want the smoother variety as the rough sort would be too difficult to work on with coloured pencils, unless you would like a more textured look.
Pastel paper is not white, it comes in a range of neutral colours like buff, grey, light blue, pink etc. The reason is because the colour of the paper can be used as the base for a pastel study e.g buff coloured paper is good for portraits. Pastels generally look more vibrant on coloured paper.
The other thing you will notice about pastel paper is that it is generally lightweight with a slight texture or ‘groove’ (otherwise know as tooth). This is to keep the pastel pigments in place, it will dust off the more shiney papers like smooth drawing cartridge papers.
I would recommend getting a pastel sketchpad if you like working in pastels as they are difficult to work with on white cartridge papers and the results are so much better. The texture of pastel papers can vary, some are more textured with a ‘sandpaper’ feel, others are smoother. This is a personal choice, depending on the way you use pastels. The grainer papers are best for softer pastels and the smoother ones for more chalk-based or ‘hard’ pastels.
I would recommend Ingres papers for pastels, they are great for all types of pastel, charcoal and coloured pencils.
Acrylic sketchpads generally have textured paper with a treated surface. They will look like a canvas or linen and will always have a ‘tooth’. Rather than the rough watercolour paper which has an uneven surface, the surface of acrylic will look like lots of little squares or lines. It is often pretending to be canvas in paper form because canvas is a typical surface for acrylic (and oils). If you touch the paper it often feels shiney rather than soft, this is because unlike watercolour the acrylic paint should sit on the top of the paper so it needs a less porous surface. Acrylic sketchpads can also be used for oil painting for the same reasons.
This grain is not for everyone, for those who work in a very detailed way it doesn’t work. The good news is that often there is a smooth surface on the back of the paper you can use instead. Some acrylic sketchpads have a smoother surface, but they are less common.
Acrylic paint strengthens the surface of paper because is has a ‘plastic’ quality so you can get away with thick cartridge paper if you don’t want to buy an acrylic sketchpad. The only issue is that cartridge paper doesn’t have a shiney surface so the acrylic paint can sink into it, making the colours slightly duller. Oil paint can’t be used with cartridge paper unless the paper is primed (another post!).
Mixed Media Sketchpads
These sketchpads are designed to be able to cope with a range of media. They are good for beginners who are testing out all the media and don’t want to get a specialised sketchpad just yet for each media. This does make sense and for this purpose I would recommend them. Once you decide which media you like I would then say it would be better to buy a sketchpad for that media specifically e.g. a watercolour sketchpad for watercolour etc.
I have found them to be perfectly adequate for all media but better with dry media (pencils, pastels, conte crayons etc.) and less good with wet media (painting) in particular watercolour. I think that watercolour work needs good quality watercolour paper, end of story. Other media is a bit more forgiving regards the paper surface so you can use a sketchpad like this for acrylic and oil.