
To continue with my previous thought, what are these challenges when making measurements? Well first and foremost when using ultra-violet and other spectroscopic systems, for the most accurate of measurements a number of conditions need to be met:
- a clear sky background,
- appropriate light conditions,
- a non-condensed plume (as in first photo on the right),
- a vertical plume or a plume which is clearly in front of a uniform background.

