I am not going to give extensive or technical explanations about light because it is not that I have great knowledge, this article is written with the intention of extending the "pills" that have been published in Instagram, if you want us to talk about a specific topic, do not hesitate to write to us at info@3dpideas.es
Visible light spectrum
The visible spectrum (Light) is divided into different wavelengths (380 to 750nm) within that band we have the different colors that we can perceive, as you can see in the table we have many wavelengths of which only a very small range can be see.
In astrophotography it is common to use filters that allow the image to be "filtered" and remove some wavelengths that mask the subject we want to highlight. It is common to use them to capture nebulae. In our case, the most common would be to use them to capture the milky way and thus obtain well-defined stars.
In the following example, although it does not have much quality, you can see the importance of filters in astro, these filters allow us to "filter" certain wavelengths that do not interest us and that "blur" or hide the subject that we want to capture.
Foto: https://www.cloudynights.com/topic/681960-best-filter-for-nebula/
To eliminate certain wavelengths we have the KASE CLIPin drop in filters, these filters are inserted into the camera body itself and allow us to eliminate certain wavelengths that we are not interested in seeing, in addition, these filters also allow us to replace the filter of our camera , if it is modified astromodified, for normal use.
What can I get if I want to take a night photo with a filter that eliminates certain frequencies? Let me give you an example.
The filters that photographers have available in square or round format are called light pollution elimination filters. These filters are nothing more than filters that "eliminate" certain frequencies of light which coincide with those emitted by certain light bulbs used until recently. little by little in our cities such as mercury vapor, sodium, etc., these are gradually being replaced by LED light.
As you can see in the previous photo, the bulbs most used in streetlights in cities "bath" the subject to be photographed in different colors, the most pronounced are yellow/orange, these colors can be tried to be mitigated in RAW by playing with the white balance but the only thing we will achieve is to change the color of the whole scene, also, normally the streetlights cause certain parts of the image to be overexposed and due to the lack of information we cannot do anything with the RAW.
KASE Neutral Night Filter
KASE has a filter that eliminates much of the light pollution. This filter is in a 100x100 and 150x150 square format for use with our filter holders and also in a round magnetic format.
After reading all of the above, we know that the night filter can be used to:
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Define the stars in our photos, be it a nebula, milky way, etc
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Take night photos in the city eliminating much of the pollution
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Capture photos of the Milky Way by removing nearby light sources that "smudge" the sky
I think it should be essential in our bags, also, if you want a perfect focus of the stars, KASE has a special filter to achieve it in a very easy way, the KASE Precision Focus in square and round format.
