Many thanks for your comments, Eric, Anirban and Simato.
The preceding one with the dromedaries could also have been great but to me it feels like you missed the timing a bit. I would have preferred to see them with high dunes in the background and very little, if any sky at the top.
Yes, the timing could have been better. I did see them passing, but the light was quite flat at the time and I let it go. The sun subsequently emerged from behind a cloud and the colours reappeared, but they were already starting down the dune. I did not mind too much, though, as it conveys a sense of "checking out" for the evening.