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Do convex lenses make parallel light rays of different wavelength converge to different points?

Do convex lenses make parallel light rays of different wavelength converge to different points? Yes. The separation of different wavelengths of light is called dispersion. Different wavelengths of ...
scottbb's user avatar
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22 votes

Do convex lenses make parallel light rays of different wavelength converge to different points?

Light from a far distance object, like a star, arrive at the lens, as parallel rays. As they transverse the lens, they are forced to change their direction. They bend inward, we call this refraction ...
Alan Marcus's user avatar
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14 votes
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What is the blue halo around objects when using a teleconverter?

The blue halo is often referred to as purple fringing. It is caused by chromatic aberration. According to Wikipedia: There are two types of chromatic aberration: axial (longitudinal), and ...
xiota's user avatar
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12 votes
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Different colors of light are disrupting my focus. What lens feature minimizes this?

You are seeing chromatic aberration — a prismatic effect which, as you nicely illustrate, reduces sharpness even in black and white photography. A lens which has greater correction for this is ...
mattdm's user avatar
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9 votes

Do convex lenses make parallel light rays of different wavelength converge to different points?

Yes, they do. This is the cause of chromatic aberration. It happens in two ways, actually. Axial chromatic aberration (also known as longitudinal CA) happens because different wavelengths focus at ...
mattdm's user avatar
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7 votes

Is it just me, or do smartphone cameras not have any chromatic aberations at all?

It is likely because chromatic aberrations are easy to fix on a fixed focal length, and fixed focus lens. And whatever remains is hidden by the heavy-handed post-processing that occurs.
xenoid's user avatar
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6 votes
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Why is low chromatic aberration considered important in the digital era?

ideal image - no abberration: simulated chromatic aberration: correcting the chromatic aberration by adjusting the RGB channel positions (in a more realistic example this would also involve ...
szulat's user avatar
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5 votes
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Why does this camera generated JPEG look better than the software generated one?

It's important to start with this: in-camera generated JPEGs are also software-generated. They're just generated on a small embedded computer with a lot less processing power than a laptop or desktop ...
mattdm's user avatar
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5 votes

Why does this satellite image of an airplane in motion show red, green, and blue bands with strange artifacts?

Looking at the imagery, it was not provided exclusively by a satellite. I work for the company that built the sensors and cameras for Digital Globe WV3 and WV4 sensors and did sensor, motion ...
mongo's user avatar
  • 343
5 votes

How do I remove the green and purple fringing from the B&W blouse in this photo?

Since the cloth is white, and the other colour is black, you could simply desaturate( remove all saturation) at whole region of cloth. I've done the same multiple times
nacfoto's user avatar
  • 106
4 votes
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Is this chromatic aberration?

Prevailing opinion seems to be that purple fringing is caused primarily by axial chromatic aberration. Chromatic aberration comes in two forms: lateral and axial. Lateral chromatic aberration is ...
Jerry Coffin's user avatar
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4 votes

How can I avoid those pink/purple lines in my portrait photos?

As established in comments, it's chromatic aberration, specifically purple fringing which you see mostly at high contrast edges in out of focus areas. You can mitigate it by closing down the aperture ...
Tetsujin's user avatar
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4 votes
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Is this just chromatic aberration? Or is something else happening in these photos?

The primary reason both images look blurry is because in both of them the point of sharpest focus is closer than most of the scene. Shooting with a wide open aperture minimizes depth of field, so ...
Michael C's user avatar
  • 175k
3 votes

How to prevent fringing?

You can't, really, unless you want to change to a better lens (they'll have that too, to some amount, but probably less obvious). Super zoom lenses like the 16-300 do always have various optical ...
ths's user avatar
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3 votes
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Vertical chromatic aberration, fixable?

Each layer of the stack shows the same effect, lessening as that area gets closer to focus. Had I done 2 or 3 more layers to get the entire thing in focus, as I normally do, it would have disappeared; ...
Michael C's user avatar
  • 175k
3 votes

How does lateral chromatic aberration correction without a lens profile work?

It is only a very slight over-simplification to describe lateral chromatic aberration as the situation in which different colours produce pictures of slightly different sizes. Seen in that light, it's ...
user51005's user avatar
3 votes
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What causes blue and red gradient/shade around black spots in photos?

The term is chromatic aberration. Is is explained in detail here: What is Chromatic Aberration?
Rene's user avatar
  • 1,233
3 votes

Different colors of light are disrupting my focus. What lens feature minimizes this?

The camera lens is a converging lens. Light rays from the subject enters the lens and the lens, due to the shape and density of the glass lens, emerge tracing out a revised path. This path resembles a ...
Alan Marcus's user avatar
  • 39.2k
2 votes

Is there an easy way to force chromatic aberration?

Find a handful of $10 yard sale grade teleconverters, preferrably designs with as few elements as possible (something like an Anker Duotelematic, NOT something like a Kenko MC7! Avoid single coated/...
rackandboneman's user avatar
2 votes

What determines whether chromatic aberration will be purple/green or red/cyan?

When considering longitudinal CA, one must see the range of colors as a linear spectrum, rather than a circular color wheel. Infrared light with its very long wavelengths is on one end of the spectrum,...
Michael C's user avatar
  • 175k
2 votes

Vertical chromatic aberration, fixable?

It's probably not diffraction. One of the problems I and others run into with focus stacking is that (depending on the lens) magnification can vary slightly depending on focus distance. This is ...
BobT's user avatar
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2 votes

What is the blue halo around objects when using a teleconverter?

As you know, the job of the lens is to project an image of the outside world onto the surface of the camera’s image senor (or film). As the light waves from the vista traverse the glass lens, the ...
Alan Marcus's user avatar
  • 39.2k
2 votes
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Is it possible to get green and red chromatic aberration?

Now the usual chromatic aberration patterns are purple/green and red/cyan but is green and red possible through simply shooting the photo? What photo? The video linked in the question is computer ...
Michael C's user avatar
  • 175k
2 votes

How can I avoid those pink/purple lines in my portrait photos?

The camera lens projects an image of the outside world onto the surface of the camera’s image sensor. During the exposure, this image is recorded. Mostly these images are tiny however image size is ...
Alan Marcus's user avatar
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2 votes
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What does Canon digital lens optimizer (DLO) do exactly?

Does it use just some generic manufacturing info or can it take into account some programmed calibration data stored in the lens, as predicted by Roger Cicala in “This Lens Is Soft” and Other Facts? ...
Michael C's user avatar
  • 175k
2 votes
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Optically reduce chromatic aberration - is it worth trying?

In short, it is not possible. I swapped out the lens to an APO macro lens, and now I have a clean CA free image.
MeSo2's user avatar
  • 131
2 votes

Do chromatic aberrations change with distance?

There are two different variables in play here: focusing distance and object distance. Chromatic aberration correction is with some priority employed to stop colored fringes to appear when focusing ...
user98068's user avatar
  • 936
1 vote

Why is low chromatic aberration considered important in the digital era?

If instead of the three (RGB) sensors in each pixel you had (say) 100 sensors, each sensitive to a range of wavelengths of 1/100 of the visible spectrum, then you would have enough data to correct ...
Keith McClary's user avatar

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