Last July I wrote a long article on the french forum about the preservation of miniature paintwork against the problems of heat, dust, humidity, ... It's mainly a problem for painters of collections who want to preserve their miniatures for life and who have to deal with extreme heatwaves in countries that weren't previously subject to these conditions, such as France or Canada. There's far too much text for me to do a quick translation, but you can read it with edge, which translates natively with deepl. Protecting your miniatures against weathering and heat https://www.bureau-aegis.org/forum/index.php?topic=17566.0 However, I haven't found any complete and serious sources in french or by AI searchs that are specific to the subject of acrylic paint, and sometimes it's a bit contradictory, I summarised everything I'd read and contacted professionals, but they didn't have any better solutions than what I'd found in my books and the archives of Canadian museums ( surprisingly, French museums are all based on Canadian research), so I only have fragments of information, but we can draw some guidelines on what to do to protect our collections. I've also concluded that it's best never to play studio level miniatures in direct sunlight, because over the years and despite a varnish, the paint will deteriorate. This means having a collection painted at tabletop level or always playing indoors. Then I also realised that, because acrylic paints are constantly evolving and because many manufacturers keep their ingredients secret, it would probably be difficult, if not impossible, to know how this paint would change over time and how it would behave in the face of the dangers that cause weathering. I've also noticed that the modelism paint ranges are all in the cheap range, as I've seen for myself from the duration of the tones of my unvarnished miniatures, which correspond to the average durability of this range. It's also noticeable that manufacturers of modellism paints never indicate the properties of their paints, whereas this is the case for the artists' ranges. You can see this on the Vallejo website, where you can find the colour protection parameters for their artist ranges but not for the modellism ranges. From what I've read, it also seems that oil paints should no longer be used if you can't guarantee their preservation, as they are extremely fragile. Perhaps my research on this subject could help you.
I consider this an important subject, because in my main painting book, some of the big names don't think it's worth varnishing, for example, and there aren't many great French miniature painters who are aware of these problems, unlike the classic professional painters I've read who talk about this issue in their books.
