This contribution to monomad's challenge is from a series of images that 'happened' on rave parties in the 90s. Being high and in the middle of things, I intuitively pointed my camera and exposed for arbitrary times. Then, on the negatives & once sobered out, I found those pictures.
I used high speed films and made big enlargements; grain size is impressive!
Shot on a lovely old Kodak Retina:

link to source
*[FB-Print] analog b/w print on fiber based paper.