Lightfastness in pastels. Is this something you’ve given any thought to?
And I haven’t.
To tell you the truth, somehow, I thought we already had a general standard for lightfastness in place.
Schmincke pastels from Germany note lightfastness on the pastel wrapper – five stars mean excellent lightfastness, one star, definitely fugitive. But when I started thinking about it, I wasn’t sure I’ve seen that notation on other pastels. So I did some quick research. I found that Art Spectrum pastels from Australia have a lightfast rating while Savoir Faire, distributor of Sennelier pastels, in their FAQs, states that of the 520 colours, only 20 are considered fugitive. So it appears some manufacturers (in Europe and Australia at least) do at least acknowledge the importance of lightfastness as an aspect of the pastels they produce.
A number of years ago, motivated by something I’d read, I did a lightfastness test in my window of some hard pastels – NuPastels – and was shocked at the fading I saw in some colours after only a couple of months. But, have I actually done that same test with my beloved soft pastels? No. And I’m not sure why not.
Perhaps partly, as I’ve said, I thought that there was a standard in place and I guess I trusted that all manufacturers would let us know about the lightfastness of pastels. I was used to using Schmincke pastels at the time and being able to choose their most lightfast colours. And partly, it was maybe a bit of head-in-the-sand syndrome, not wanting to know the truth.
But the truth has arrived and it ain’t pretty.
Near the end of this post, you’ll find a video. It’s a presentation by Michael Skalka, Chairman of Subcommittee ASTM D01.57 Artists’ Materials. It was given at the President’s Forum at IAPS (International Association of Pastel Societies) in Albuquerque this year. And now IAPS has made that presentation public. On their YouTube channel. For ALL to see. The truth is out
I’m going to give you a bit of a summary of the video but I urge you to watch the entire presentation as it’s fascinating, eye-opening, and a potential catalyst for change.
So, the pastel standard.
How this all happened
It has a number – D8330 – and was created by ASTM (American Society for Testing and Materials), now known as ASTM International.
What’s ASTM you may be asking? According to Wikipedia, it’s a “standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services.”
D01 is the subcommittee for Paints and in the late 1970s, early 80s, a subcommittee was formed specifically for Artists’ Materials – D01.57. Probably the most well-known of these is D4236 which is the standard practice for labelling art materials for chronic health hazards.
The current focus is the ASTM standard specifically for pastels – D8330. IAPS has served on this subcommittee for nearly 20 years and has been an ongoing, hard-working advocate for the completion of the testing. And we should applaud them for the work they have done on our behalf!
So back to the presentation. A number of pastels were donated by a few manufacturers and the rigorous test method used to test watercolours, oils, and acrylics was applied to these pastel samples. Tweaks had to be made to adjust for this medium. And the tests were done again.
Benefits of the standard D8330
In his presentation, Michael reviews the benefits of the standard D8330 for lightfastness of pastels. These include:
- It provides a uniform way to test and compare products
- A standard to establish a level playing field for quality manufacturing and that the public can rely on
- The means for artists to lobby for better products.
Addressing criticism of the standard
When the test results were finalized and the findings presented (and as you’ll see, they are quite shocking), there was some resistance from the manufacturers to the publication of the results. One criticism was that compliance would be too difficult, that it would entail work. Yes, undoubtedly it will.
One of the most sensitive issues was the worry that many beloved colours would need to be eliminated as they are not lightfast. Well yes, but as Michael says, isn’t it better to at least let artists know when colours are fugitive? Then we can decide whether to buy them and how to use them.
And, something to consider, all other art media are labelled with their lightfastness. It’s just pastels that aren’t!
Visual appearance of light testing results
At this point (about 21 mins into the presentation), Michael shows a few examples of colour swatches. They show the original colour, the swatch exposed to indoor lighting and the swatch affected by sunlight.
Here are a couple of examples. (You can see the others in the video below.)
Rather horrifying isn’t it?!
Notice that not only do some colours fade, they turn to grey!
Summary of test results
We are are presented with an alarming summary of the test results. Of all the colours tested, only 48% achieved a lightfastness rating of I (Excellent) or II (Very Good). That means that over half of the pastels failed to reach this level of lightfastness, the level that we ideally want all our pastels to achieve.
So why did over half of the samples do so poorly? The suspicion is that they are dye-based rather than pigment-based.
Dyes will fade over time. All those gorgeous high chroma colours that dazzle us? They do so at the expense of potential fading. In fact, in the test, some of these dazzling colours started to fade within two to three weeks. Michael reports that some were fugitive within days!! The truth is that dyes cannot withstand light exposure.
Wow. If you’re like me you’re kind of in a stunned place right now.
I mean, aren’t you shocked that there’s been no standard of lightfastness for pastels until now?
Aren’t you dismayed that so many of our beloved pastels may be fugitive and that we had no way of knowing this before (unless we had performed our own tests)?
So what can we do about all this?
The first thing is to understand that ASTM International is not a regulatory or advocate body. They just do the tests. There are no enforcement policies and there are no penalties. This means that change can only come from us, the consumer, requesting manufacturers to use safe, permanent, lightfast pigments. And if we want them to continue to produce those colours that may not be lightfast, we need to ask that they be labelled as such. That way, we know what we’re getting.
Michael encourages us to first do our own testing.
Take some of your favourite sticks and make swatches of them. Label them by brand and identification number (if you can find one). Cover half of the swatch with an acid-free piece of matboard or illustration board, something that will prevent light from affecting the covered colour swatch. Then put it all on a windowsill. Select a north-facing one that receives bright but indirect light. Set a timeframe. Maybe check them in a month. Or wait a couple of months. You could also set a duplicate group of swatches in a south-facing window and compare what happens.
Don’t worry about testing the earth colours as they are probably all lightfast. Choose the glorious reds and pinks and bright yellows and blues. And then, wait to see if any of them fade. If they do, you have evidence in hand to report to manufacturers. Based on Michael’s suggestion, we can write something along these lines:
Dear —— (name of pastel manufacturer), I love your pastels but I would very much appreciate it if, going forward, your pastels conformed to the ASTM standard D8330 and that your pastels were labelled according to their lightfast rating. That will give me confidence that the pastels I use will create paintings that will stand the test of time.
(Remember, you can always watch the video on a faster speed by clicking on the gear icon at lower right. x1.5 times works well.)
Imagine not knowing if your watercolours will fade. Or your acrylics? Or your oils? We take it for granted that all these painting mediums are labelled with lightfastness ratings. So shouldn’t we expect the same for pastels?
It’s up to us to ask for change. If we do nothing, nothing will change.
Do you want to know if your pastels are lightfast? I sure do. I want my pastel paintings to be enjoyed, in the years to come and be as colourful as they are now, not a washed-out shade of grey. If enough people make these requests of manufacturers, we can hope they will listen.
We know there will be a lot of work, effort, and cost involved with this kind of transition. But don’t we, the consumer, the artists who love using pastels, deserve to at least know which colours are lightfast and which will fade?
Change is hard. And turning the ship of business isn’t easy. We understand that. But we need to come together as pastellists to encourage and urge manufacturers to adopt the pastel standard. Now that we know, now that the shades are off our eyes, we are no longer ignorant. So shall we take this on? We can do so with compassion and collaboration.
My tendency is to want to tiptoe around this very hot topic but, the evidence is in. Do we ignore it or do we act on it?
Leave me a comment about your thoughts, any ideas you have, or any questions that may have popped up on reading this post about the lightfastness of pastels.
Please also let me know if you’re going to do your own lightfast test with your pastels. That’s our first step. Let’s do this!
Until next time,
PS. A big thank you to Richard McKinley, IAPS President, for reviewing my first draft of this post and making valuable suggestions and corrections.
PPS. Apologies for this text-heavy post!!