What is the luminous word written in the air? Can I take pictures with a SLR?

In fact, the luminous characters written in the air are not constantly glowing, but left by the naked eye. If you look at them clearly, they are a complete word. SLR can be taken, but the exposure time should be adjusted a little longer;

Light painting: also called light painting photography. As the name implies, it is a photographic work with light painting as the creative means, and any light source can be used as part of the imaging effect. If you want to create a particularly illusory or interesting light painting, you can also shake the camera deliberately, but the effect will be difficult to predict, so you need to try more, which is another advantage of digital cameras.