Optolong L-eNhance filterThe Optolong L-eNhance filter is fast becoming the talk of the astro town. It’s affordable for even the tightest astro budgets but also delivers exceptional performance for imaging emission nebula and super nova remnant from light polluted cities.

What is this filter though and how does it work? Why do you need it?

If you’re part of the growing number of astrophotographers that are imaging from their own astro backyard, then you’ll be dealing with city street lights and neighbour outdoor lights in addition to cloudy nights! So for those few clear nights we get, we want to make the most of it and the Optolong L-eNhance filter can help tremendously.

Veil super nova remnant captured by Ron Brecher using an Optolong L-eNhance filter
Veil super nova remnant captured by Ron Brecher (astrodoc.ca) using an Optolong L-eNhance filter

The Optolong L-eNhance filter is designed for use with one shot colour cameras (OSC) , such as a DSLR or cooled cmos camera dedicated for astrophotography. As example, I use a QHY168C.

This filter acts like an FM radio, tuning in specific channels. In this case specific light channels. It isolates the H-alpha, H-beta and OIII light transmission line while blocking the rest making it ideal for imaging with in light polluted areas.

optolong l-enhance filter light transmission curve graph

This graph shows the light transmission lines the Optlong L-eNhance fitler isolates.

Transmission lines the filter allows through:

  • H-alpha: 656nm
  • H-beta: 486.1nm
  • OIII: 501nm

By isolating these wavelengths of light, the filter can achieve some stunning results when imaging emission nebula and super nova remnants. It can also be used during nights of moonlight to image. There’s many great images of deep sky objects taken by astrophotographers using this filter during clear nights that the Moon was up. That’s definitely a bonus. Did I also mention it’s a very affordable!

If you’d like to know more about the Optlong L-eNhance filter, watch my video below. In it I talk with Dr. Ron Brecher (AstroDoc.ca) about this filter and look at what his results have been with it.