TCA is the most noticeable towards the edges and virtually disappears in the middle of the frame. Move the main subject away from edgesĪs I mentioned earlier, you can avoid LoCA by stopping down the lens, but how do you avoid the TCA? You can experiment with your lens to figure out which aperture value gives the best quality image, but as a rule of thumb you should stop down by at least one or two stops from the widest aperture of your lens to avoid chromatic aberration.Īs you stop down the lens, you will lose shallow depth of field additionally, you’ll also have to use slower shutter speed and higher ISO setting to make up for the loss of light and avoid unsharp images. Firstly, CA is the most noticeable in high-contrast situations secondly, shooting during the low-contrast times of the day, such as the golden hour, usually produces better and more eye-pleasing results. Avoid high-contrast scenesĭon’t take this advice too literally it’s completely fine to photograph contrasty scenery, but be mindful of difficulties it brings. If you’re all about image quality, you might want to consider using prime lenses instead of zoom lenses and while you’re at that, expect to spend quite some money to get a high-quality lens that will create images with the least amount of CA. More often than not, zoom lenses are more affected by chromatic aberration than prime lenses, especially at their minimal and maximal focal lengths.įor example, if you own an 18-200mm lens avoiding both 18mm and 200mm will guarantee the best results. The easiest way to get rid off CA is to import an image into Lightroom, navigate to Develop module, open Camera Correction panel and check Remove Chromatic Aberration. Lightroom will automatically analyse your image and remove CA. RAW images are crucial when you intend to post-process them in software, such as Adobe Lightroom or Luminar 4 uncoincidentally this is how you’re going to remove CA. Shooting in RAW has a lot of advantages, and if you’re seriously into photography, you should already be doing it. I’ll show you how to minimize CA to the point where it won’t be a problem. At this point, you might think, “great! Another problem to worry about”, but let me put your mind at ease. I’ve explained what chromatic aberration is, what causes it, and what it looks like. TCA can be quite easily removed or reduced with post-processing software, such as Lightroom. Furthermore, TCA won’t appear at the centre of the frame but becomes significantly more noticeable towards the edges of the frame, especially in high-contrast areas. TCA is typical for short focal lengths, and unlike with LoCA, stopping down the lens won’t help. Light breaks differently based on where it passes through the lens, producing a shifted image. A scheme of lens that produces lateral chromatic aberration. Lateral chromatic aberration, also known as transverse chromatic aberration (TCA) , occurs when different wavelengths are projected to different points in the focal plane. Lateral (Transverse) Chromatic Aberration While long focal lengths and fast prime lenses are more likely to produce LoCA, stopping down the aperture helps reduce LoCA as it increases the depth of field so that the all the wavelengths are still in acceptable focus. Longitudinal chromatic aberration leads to colour fringing around subjects throughout the entire image, in the centre as well as on the edges. Different wavelengths break at different angles on the glass and consequently hit the sensor unevenly, producing colour fringing. Longitudinal chromatic aberration (LoCA), also called bokeh fringing, occurs when different wavelengths that pass through the lens are focused at different distances from the lens (focus shift), as shown below: A scheme of lens that produces longitudinal chromatic aberration. Longitudinal (Axial) Chromatic Aberration All colours break evenly on the glass and hit the sensor in the same point.įor now, this is impossible, so we have to deal with two types of CA – Longitudinal (Axial) Chromatic Aberration and Transverse (Lateral) Chromatic Aberration. This effect becomes the most noticeable in high-contrast settings, where it significantly blurs images and causes coloured edges.Ī theoretical, perfect lens would be able to focus all colours into one focal point, as shown in the image below: A scheme of lens that doesn’t produce chromatic aberration. Chromatic Aberration (CA) is an unwanted optical effect that occurs when a lens doesn’t refract all the wavelengths of light into the same point.ĭifferent wavelengths (=colours) travel at different speeds through the glass of a lens, resulting in light dispersion.
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