6 months ago I started a test to check the lightfastness of Hydrus Fine Art Watercolour by Dr. Ph. Martin's as compared with Winsor and Newton Artist's Watercolour which has a measured lightfastness rating. Previous posts on how, and why I decided to run this test are HERE.
As you can see from the above image, and compare it with the image from the start of the test, there is no fading. The slightly lighter appearance of the red at the top righthand side is due to my application of the watercolour and can be seen in the original image too.
The Hydrus colours are the top 3, the Winsor and Newton are the 3 at the bottom.
I was expecting to see some evidence of a faded edge line where I'd placed thick card to create the unexposed areas, but there is none.
This test sheet has been sat in a south facing (ie: direct sunlight) for 6 months. The area on the far left has been unexposed, the next section exposed for 2 months, the next for 4 and the far righthand side has been exposed for the full 6 months.
The weather has been bright and sunny on the whole. You would never put a watercolour painting in direct sunlight, so this has been a tough test for the pigments. The Hydrus colours have stood up to the task brilliantly, and I'm now confident that I can produce water based woodblock prints with either the Hydrus colours or the Winsor and Newton watercolours without any fear of fading.
The good thing about the Hydrus colours is that they're so quick to use straight from the bottle and diluted with water. One drop of colour goes such a long way, and by using the pipette each bottle contains, it's easy to keep a record of mixing and diluting measurements just in case you need to remix another amount. I just wish they were more readily available in the UK. I had to order mine via mail order in the US.
I hope others will find this test useful when deciding which materials to use for their art projects.