Updated 29/8/14 to include Baader U 2012.
The current ‘gold-standard’ reference UV-pass filter is the Baader U filter. This filter is essentially a thin UG11 filter with multiple layers of dielectric coating applied to it. It has sufficient IR-block to prevent any IR-contamination of the UV image.
While it is thought to be the best UV-imaging filter out there, it is certainly not a cheap filter, and the price seems to go up with each passing year, making it even more out of reach to many who may be interested in UV-imaging. Hence it is worth considering if there are any more affordable options out there. I have shot the same flower with the different filter stacks, so the resulting UV image can be compared. Continue reading UV-Pass filters – a comparison