Queen of the Night blooms at night. By next day morning, the flower would have withered. Furthermore, the flowers bloom only once a year. The short life means that the flowers cannot be photographed if one is not ready at the right time.
When a Queen of the Night started to open in my garden, I kept a watch. At around 10 at night, the petals had opened up. But the light was low and I could hardly make out the flower in the darkness.
A flash did not produce the desired result. I then used an LED light. It was directed upwards at the flower. Exposure was f/4.5 at 1/50 sec. ISO rating was 400. Subject distance was 380 mm. I made several shots and then photomerged them together in Photoshop.