There are two paintings by German artist Hans Mielich that are relatively well known by music scholars in general and trombone scholars in particular: Outdoor Feast (see 1549, below) and the artist’s depiction of the Bavarian court orchestra (see 1563-70, below). Those two paintings are included in recent books on the history of the trombone.
However, there are several other paintings by the same artist that are not as well known; to my knowledge these other images have not been discussed or included in any recent scholarly books or articles on the trombone.
Like Mielich’s depiction of the Bavarian court orchestra, they originate from manuscripts that are collections of printed music. They are visual embellishments, called illuminations, that are normally small in scale and are meant to illuminate, decorate, comment up, or expand upon the material in the manuscript (in this case the music, although historically, illuminations are more likely to occur in books of religious writings).
In terms of subject matter, these 16th-century paintings depict the Renaissance trombone in a wide range of settings, including mythological, decorative, and sacred. Trombones appear to be playing both outdoors and indoors, both loud and soft, both secular and sacred. The implication is that the Renaissance trombone was a diverse instrument that participated in a wide variety of musical activities.
1549—Munich, Germany: Outdoor Feast, a painting by Hans Mielich (Müelich), court painter for Duke Albrecht V, depicts an outdoor wedding banquet. The music ensemble includes 2 trombone players, one of whom appears to have multiple instruments in his hands and is apparently in the act of switching from one trombone to another. The painting also shows, in a different area, a dance band consisting of 2 trombones and another instrument (probably a shawm) (see detail and full image below; public domain image) (Kenton plate 14; Buchner plate 95).
1559—Munich, Germany. A collection of works by composer Cipriano de Rore, illuminated by court painter Hans Mielich, includes several images of trombones (see below 3 images; public domain) (Bayerische Staatsbibliothek, Mus.ms. B).
1563-70—Munich, Germany: An elaborately illuminated 2-volume manuscript of Orlando di Lasso’s collection of motets, Psalmi Poenitentiales or Busspsalmen (Penitential Psalms), includes several depictions of trombones. The illuminations are by Hans Mielich, painter for the Bavarian court. In the most famous image (see top image below), a contemporary depiction of the Bavarian court, Mielich depicts Orlando di Lasso, seated at the keyboard, with his ensemble of court musicians around him, including trombone, cornett, woodwinds, and strings. That image and the 2 images following it (below) come from the second volume of the manuscript. The final 3 images below are from the first volume (public domain images) (Munich, Bayerische Staatsbibliothek, Mus. Ms. A, I and II).