0% vs 25% vs 50% vs 100% Cotton Watercolour Paper

Thanks, Teoh. This information is really helpful. I'm fairly new to watercolor and have been slowly buying supplies over the last few months. I have to practice a lot and paper can be quite expensive.

It would be great if you would run these same tests on some popular sketchbooks, like Stillman & Birn Beta or Pentalic.

I agree with Tina about Stillman & Birn Beta and Pentalic

Perhaps a comparison of the paper that has been my favorite for a couple years now: Stonehenge Aqua cold press (it is 100% cotton but a few dollars cheaper per sheet than Arches).

Thanks, Teoh. These tests reveals lot of good information. I have used Arches, Fabriano Artistico and Winsor and Newton (all 130 gsm, cold pressed). My experience with Arches is good the only issue is they are little bit rough. I liked W&N much, for some reason my paintings look fresh on them. I have not experience on Fabriano Artistico, since the pad I have is small 7*6 and I don't use it much. waterford saunders is next on my list.

I can't see on the scans and I wasn't able to see on your video either, where exactly is that super high quality of Arches paper. If for one thing the Arches paper that you tested looks like it has a defective sizing.

The blue paint glazing had white spots while the edges were uneven on each and every brushstroke of colour you applied on it. That happens when the sizing is not strong enough or not consistent on the surface of the paper allowing the colour to spread and get absorbed in some areas of the surface and stay on top on some others.
The yellow washes looked washed out on both of the 100% cotton papers. To be honest I was expecting this to happen on the Fabriano Artistico as it is well known that Fabriano had the recent years some serious problems with its papers and particularly with the Artistico line. But I didn't expect that from the Arches ( though I have read some really negative reviews recently) that it is marketed as a top quality paper and it is by far the most expensive paper of all.

The papers that IMHO performed better on your test are the Fluid and the Fabriano 5 each on their own category.
The colours looked brilliant on the Fluid paper, the lines and edges were sharp ( something that is very important when you paint details), the blending results were decent for a non cotton paper and the diffusion of colours gave very good results too.

The paper Fabriano 5 gave the best results.
The colours looked brilliant, blended nicely, the glazing was as it should be with clean and sharp lines on all the length of the blue brushstroke and the diffusion of colour in the wet on wet application, though it wasn't that smooth, it was extented enough to make our lives easier when we paint wet on wet.

To conclude:
The most important thing for a watercolour paper is the sizing. If the sizing is not hard enough or it is defective then the paper will perform as an expensive blotting paper.

Dear Teoh,

Thanks for doing these detailed tests. I think I understand a little bit more about my experience moving from only painting in Fluid Blocks to trying Arches for the first time. In many ways I had to relearn how to paint. Several techniques that produced bad results before now produced amazing results (wet in wet charging). And several things I know about how much paint to mix also was completely thrown off.

I've come to conclude the art of painting on cotton paper is a separate thing with it's own nuances, as is the art of using cellulose. And both of them defiantely have their own place. Cellulose papers are undeniably cheaper and it does mean I try and paint a lot more on them without the fear of wasting paper.

Thank you for this excellent analysis. The lesson seems to be - get to know your paper! One point that appeared but briefly and I think is worthy of further mention is the sizing applied to each paper and how you treat it. For example, I use a Ken Bromley paper stretcher and the instructions that came with it say that you should soak your paper for several minutes before stretching it. Th8s seemed to remove most if not all of the sizing and left me with blotting paper. After experimentation I now only soak the paper for 5 seconds and then let it rest foe a couple of minutes before stretching it. That seems to give me a good consistent result. Hope this helps.