A few years ago, I won't have many options for watercolour papers or medium in Indonesia as I have now in the UK, such as masking fluid, a latex-rubber fluid that is applied to retain the white watercolour paper or wash underneath. I used to know only Winsor & Newton art masking fluid.
Since I start practising botanical art which often requires delicate details and sometimes a very tiny area to preserve, I made a time to browse a better option for masking. I found Pebeo drawing gum and I am happy I did it!
I like that Pebeo is significantly coloured (grey). It is nice to easily see where the masking is already applied. I love that Pebeo is thinner or more liquid than W&N masking fluid, so it is easy for making sharp edges and reaching the paper's deep texture quickly. I'm also fond of Pebeo for lasting a long time and not making solid gum on the bottle's neck and cap when not in use. I like that the cap is also easier to open than W&N.
I haven't tried other brands yet. I heard about other masking fluids whose bottle has a special nib so I don't need a brush and just gently squeeze the bottle to apply the masking. I may tried them later but for now, I am happy with what I've had. I never be worried about paper tearing or brush clogging as long as the masking fluid used appropriately. Read more tips HERE.
Comparison of the colour. Using dip/ ruling pen will give thicker masking and so darker colour than using a brush. Since I use brushes more often, I prefer the grey Pebeo that is easily seen on white paper.
Comparison of the thickness. I can't show you well the significant difference of thickness between Pebeo and W&N masking fluid but it was easier for me to move the brush/dip pen with Pebeo than W&N masking fluid. You can see the the branch silhouette in left painting has longer and steadier strokes.
Comparison of the sharp/clean edges. I love that the anthers of flower in the left image have sharper and rounder edges than the right one.