Using Filters for Nighttime Photography
- By: Luis Argerich
In general terms the wise advice is to remove all filters when you are shooting at night. There are several good reasons to do this. First of all any filter will cut some of the light that reaches the sensor so they will make your photos darker and you will need longer exposure times. Most importantly, filters create internal reflections of your light sources and that produces artifacts in your photos, if you see halos, flares and strange things it is probably because of a filter. Having said that, some filters can be used for interesting effects at night. This short article will show you which filters are good at night and when to use them.
1. Please Remove the UV filter
The UV filter is really a bad bad thing at night, it creates reflection and refraction problems from your light sources, you will have flares, halos and artifacts in your photos that can be avoided just removing the filter. You can check the article “what you need to know about UV filters for more information”
2. The Fog Filter
A fog filter in landscape photography is used to add a foggy look to a landscape. At night the fog filter can make the stars bigger without defocusing them. This is nice for constellation photos or to give the stars a better look when you shoot a landscape. The fog filter will also avoid saturating the stars losing their color. It’s a great tool to capture the real colors of the stars. The Tiffen double fog filter is a good example of this type of filter.
3. The Didymum Filter
What a name! A didymium filter is also known as a “red intensifier” which it basically makes reds more prominent in the photo without chaning the white balance of the shot a lot. It is used in landscape photography to enhance fall foliage, sunrise and sunset shots. At night the didymium filter is known as the “poor man light pollution filter” because it helps mitigate the effects of light pollution in the photo. It also enhances contrast and provides good color for moon shots taken near sunset or sunrise. Finally it also enhances red nebulas if you take deep sky images with long exposures. The Hoya red-intensifier is an example of this type of filter.
4. The Star Filter
The star filter is simple, it creates diffraction spikes on pointed light sources. This is a good filter to make bright stars very prominent in the photo. There are variations with 4,6 8 and more spikes. The 4 spike filter emulates the diffraction spikes from a telescope secondary mirror (spider). The 6 & 8 spikes filter simulate the diffraction spikes created by the lens aperture. A good trick is to take two shots with and without the filter and combine them using only the stars from the filtered shot, the rest of the scene is then not affected by the fuilter and free of artifacts. Hoya makes several good quality star filters.
This filters can make our night time photography more fun they are good tools to have and to experiment, of course we can’t enhance any photo with a filter but it’s good to know when they can help us.