Wednesday, 2 October 2013

Lightfast tests - seven months

I painted a number of swatches of as many colours as I could find back in January, cut half away to store in a dark drawer, and placed them in a north facing window for the last 7 months. For the first two months they were inside the window, for the next 5 they were stuck on the outside protected only by the plastic sleeve they were in. There was almost no change at all after the first two months, but a bit more now.

First are photographs of each full sheet. They are too large to fit the whole sheet in the scanner, which was not very thoughtful. Next time - A4 sheets!

Then I will go through each scanned section so you can see what colours faded and which have remained - so far.

Lightfast tests page two seven months
Lightfast tests page one seven months


All Daniel Smith colours. The only change is Aureolin,  6th on the top line. PY40 is known to go grey and you can see this very clearly in the diluted wash on the left. Please don't buy or use this colour.




All Daniel Smith colours. No fading evident after 7 months. Note that Quinacridone coral looks different in the scan, but not in real life. One to watch. 

All Daniel Smith colours. It is difficult to see on this scan, but Rhodonite, second on the top line, has lost some of the rose and greyed slightly. Not recommended. All others are fine so far.
All Daniel Smith colours. Prussian Blue 2nd on the bottom line has changed slightly, and was the first to change when I checked last time. Vivianite Genuine has lost some of the blue hue, so is not recommended. Turquoise Genuine and Sleeping Beauty Turquoise have also changed - the Sleeping Beauty has noticeably greyed. All others seem stable to far.
All Daniel Smith colours. I couldn't see any changes in any of these colours.
All Daniel Smith except the final Old Holland Emerald Green. I couldn't see any changes in any of these.
Most of the top row are Daniel Smith, but you may notice Old Holland Manganese Blue with it's genuine granulating pigment, Art Spectrum Sap Green and Old Holland Flesh tint, which has lost it's red tones so is not stable.
On the bottom row are a set of traditional Japanese pigments. Not that the yellow pigment used in traditional Chinese and Japanese colours is not lightfast so has faded out of the greenm the yellow and even the colour that looks like burnt sienna. The Blue on the right has also changed. 
This final image shows traditional Chinese pigments and the faded yellow is even more obvious. The crimson is probably Alizarin PR83 but I don't know for sure - it has obviously faded.
On the bottom row is a Liquitex Hooker's free, some Art Spectrum colours and some Daler Rowney and lefranc et bourgeois colours that have survived fine so far.

So the main problem colours are PY40 Aureolin, Chinese and Japanese yellow, Prussian Blue, a number of Primatek colours (though MANY are fine) and some crimson reds. Surprisingly, the Opera Rose has not faded as expected...yet. I'll put them back in the window and report back in a few months.

September 2014 update here.

6 comments:

  1. Great work, Jane! Certainly a surprise about the Sleeping Beauty (bad) and the Opera (good). Are you still using DS Carmine? (I didn't see it in your tests.) Thanks for posting this!

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    1. I am still suspicious about Opera Rose all the same! From everything I've read it won't last so I painted it there as my control, along with aureolin. I won't say 'it is good' but it is certainly fine so far in my tests. It's not a colour I use since I am a realist and I'd rather use Quin Rose or Quin Magenta for that bright pink look.

      I still use Carmine in my tiny travel palette as it takes the place of both Quin Rose and Pyrrol Crimson. It's such a lovely 'primary' red option. In a slightly larger palette where I have space for more pigments I use a Quin Rose PV19 and Pyrrol Crimson to increase the range further - Pyrrol crimson is deeper in mass tone than Carmine.

      Carmine isn't in those tests as I ordered it later, but is in another I am running and is doing well so far. I'll post that one up too - I painted out all the colours that I love and use, rather than all the colours I had! I also did it in A4 as two separate sheets so it is easier to scan.

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  2. Hi Jane, thanks for all your efforts with this. Were there any further changes after seven months?

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    1. That's a good question! They have been up for another year now so I'll take them down and have a look and report back :-) Watch this space next week....

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  3. That Prussian blue result is a little concerning. I've seen mentions of the pigment being one tier below the top lightfastness going back to the 1800s, so it's been known that it can fade, but supposedly the "best" (i.e. Milori) variety of it doesn't. Handprint's lightfastness test showed that Daniel Smith's version didn't fade, but here yours is showing it does, or can. That's the concerning part. It means we can't just trust that brand x won't fade because it didn't in one test.

    By the way, Prussian blue is an oddball that I've read will recover its color if left in the dark long enough. At least in oil paint, though I haven't tried. Did you ever see that in watercolor?

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    1. It surprised me too - I'd never some across a bad lightfast rating for it. It's worth keeping in mind that Sydney has pretty intense sunlight. In many countries perhaps it just wouldn't be a problem. I've not heard about putting it in a dark place to recover!
      Anyway, I make a Prussian Blue hue by mixing phthalo blue GS with a touch of a warm red so I don't have it in my palette, just to be on the safe side.

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