Many watercolour paper makers produce two or three surface textures in their range. The textures are called Rough, NOT (Cold Press) and Hot Press. Since it is the most versatile some paper makers only make NOT. Each range of textures will vary according to the manufacturer, what is called Rough by one maker might be smoother than Rough by another maker.
The texture could be described as pebbly, with hills and valleys. The texture will affect the watercolour paints by making the colour lighter on the ‘hills’ and darker in the ‘valleys’ as the wet paint collects there. Also, paint applied with a nearly dry brush across the texture can leave little white ‘sparkles’ of paper that are left unpainted. So you can choose which paper to use based on the subject in the painting. For example you might want to use Rough when painting a tree whose bark is rough and Hot Press when painting a silver bowl that you want to be smooth and shiny.
- Rough is made by placing wet sheets of paper against textured felt blankets, or air drying, or both. It has a lot of texture and is a bit softer and more absorbent as it hasn’t been compressed. Some advanced artists like the challenge of the high texture and it can be quite expressive.
- NOT texture (Cold Press) is the medium texture of the group, not too rough and not too smooth. It is somewhat compressed. It is the most versatile texture and is used for a wide variety of watercolor effects from washes to detail work.
- Hot Press has been ironed very smooth between hot rollers and it is primarily used for detail work due to its smooth finish. The extra compression means it is less absorbent. Botanical artists often paint on Hot Pressed paper.
The compression between the hot roller for Hot Press or cold rollers for NOT (Cold Press) affects the absorbtion of water and paint and the ability to lift out colour. Some artists find the Rough quite absorbent and the Hot Press very slippery and not-absorbent.
Machine made, mouldmade, and handmade papers will have different characteristics of texture showing the texture of screens and wires use to make them that also affects the irregularity of the pebbly texture.