The Optolong L-eXtreme filter has narrow 7nm band passes in the Hydrogen alpha (Ha) and Oxygen III (OIII) lines, unlike the older Optolong L-eNhance, which also has a band pass at the Hydrogen beta (Hb) line. The Optolong L-eXtreme will block out that extra bit of light pollution by omitting the Hb line, while retaining all the detail from emission nebulae by capturing the targets in Ha and OIII.
With so many different light pollution filters available it’s difficult to know which one to get. The Optolong L-eNhance narrowband filter has been a complete game changer for my astrophotography. If you’re using a one shot colour camera (CMOS, CCD or DSLR), then you need to be seriously considering adding this filter to your arsenal.
The Optolong L-eNhance is a tri-band pass filter, allowing Hydrogen alpha (Ha), Hydrogen beta (Hb) and Oxygen III (OIII) wavelengths through. Isolating these 3 specific wavelengths is key when imaging nebulae such as the Heart nebula (IC1805), and your camera will filter out all that nasty light pollution that can be so damaging for us backyard astrophotographers.