The Optolong L-eNhance filter

to check on one’s list of preparations for imaging emission nebulae is the phase of the Moon. Bright moonlight typically washes out all but the brightest emission nebulae, so most imagers simply wait for moonless nights to shoot these colourful objects. The typical exception to this rule is to image them using monochrome cameras and special narrowband filters that isolate specific regions of the visible spectrum where these ionised gasses emit light. Narrowband filters also block most moonlight as well as many sources of light pollution, so amateurs equipped with these setups could shoot