132
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Why are Red, Green, and Blue the primary colors of light?
TL:DR
Do primary colors really exist in the real world?
No.
There are no primary colors of light, in fact there is no color intrinsic in light at all (or any other wavelength of electromagnetic ...
- 176k
51
votes
What's it called when white objects or white backgrounds become blue in photographs?
This is called a color cast.
As others have said, it is a result of an incorrect white-balance. Your camera is assuming that light is of a different color than it is and is compensating for that, ...
- 103k
47
votes
Why do we use RGB instead of wavelengths to represent colours?
The goal of the imaging engineer has always been to capture with the camera a faithful image of the outside world and present that image in such a way that the observer sees true to life picture. This ...
- 39.5k
43
votes
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Should I shoot color or black and white 35mm film to learn photography fundamentals?
If your goal is to practice composition and work with shadows and lighting cheaply and efficiently, then you should shoot digital, not film. You will get more immediate results, and the ability to ...
- 33.2k
41
votes
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Water behind ships much bluer than rest of ocean
Is this an effect like HDR or plain photoshop (post processing)?
I'd say neither. The effect is natural. The ships' propellors churn the water quite a bit, causing the wake to become aerated. This is ...
- 33.2k
40
votes
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Why don't cameras offer more than 3 colour channels? (Or do they?)
Why don't cameras offer more than 3 colour channels?
It costs more to produce (producing more than one kind of anything costs more) and gives next to no (marketable) advantages over Bayer CFA.
(Or ...
- 5,525
36
votes
Why do we use RGB instead of wavelengths to represent colours?
You said,
this is the information that is captured at first by digital cameras.
That is not correct. By themselves, sensors on most digital cameras respond to a broad band of frequencies of light, ...
- 33.2k
33
votes
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Will a lens upgrade from the kit lens give me better colors on my backpacking travels?
"Better image quality."
You use that phrase.
When we say image quality in reference to comparing two lenses, we rarely are talking about anything with regard to which one is "... less dark and gives ...
- 176k
27
votes
Why are Red, Green, and Blue the primary colors of light?
We ended up with RGB because they're a reasonable match to the way the three types of cones in our eyes work. But there's no particularly privileged set of wavelength choices for Red, Green, and Blue. ...
- 3,033
26
votes
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Is the white balance wrong in these field poppy pictures?
What is going on?
I compared both pictures of the field (left out the one with the tractor, as it suffers from the same problem as the other over-exposed picture, IMHO) in After effects. The image ...
- 6,478
25
votes
Water behind ships much bluer than rest of ocean
Many navy ships intentionally inject air into their wake to obfuscate their sonar signature. See Prairie-Masker air system
This added air gives the wake a light blue hue, and since the air bubbles ...
- 359
22
votes
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What techniques were used in this late 1970s car ad featuring a family picnicking with giraffes?
More than a comment, less than an answer, because I have no clue what camera/lens/film...
The car's registration plate sets it firmly between August 77 & July 78 - the letter is the year for old ...
- 23.4k
19
votes
Why don't cameras offer more than 3 colour channels? (Or do they?)
A few notes from this long-time optical systems engineer. First, there are things called "hyperspectral" cameras which use gratings or equivalent to break the incoming light into dozens or ...
- 1,887
19
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What causes the fake colors of stars on these pictures?
I can tell 3 common reasons for weird/fake colors in astrophotography:
Chromatic aberration makes some starts appear white in the center, but their borders blue or red, depending what of those two ...
- 1,251
19
votes
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Why the color is different in two pictures in similar conditions and setting?
The camera's metering system and auto white balance system are basically a database of many shooting scenarios, and the camera tries to "guess" what you are shooting and how you want it to ...
- 12.6k
17
votes
Help for a film shooter: how to cope with the paradox of choice?
There's no one way.
Personally I find digital frees me to defer choices until after the shot. Not only that but I can "discover" new interpretations of a scene with different crops, different toning,...
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16
votes
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How can I maintain brightness in a landscape without overexposing the sky?
How can I make my shots look like this one?
I added an emphasis to the question you asked, which is pretty much the answer: You make an image like that.
There's no way your camera will produce an ...
- 8,544
15
votes
Photoshop's color replacement tool changes to grey (instead of white) — how can I change a grey background to pure white?
Graphic Design Stack Exchange: How to cut how hair accurately
Advanced hair extraction tutorial
First off, plugins and simpler methods are available. This is if you want to get higher quality results.
...
- 2,457
15
votes
Accepted
What's it called when white objects or white backgrounds become blue in photographs?
Your camera, for whatever reason, is setting the color temperature and white balance at different points for the two images.
That gives it what we often call a color cast, tint, or hue which simply ...
- 176k
15
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Accepted
What colour scheme for model aircraft should I use to give a realistic black and white film photo?
I would not worry overmuch about the color schemes.
Two reasons:
the emulsions you mention (Bergger and HP5+) are panchromatic, in both cases with rather decent color rendition
your scenes will ...
- 5,990
14
votes
Why don't cameras offer more than 3 colour channels? (Or do they?)
RGB camera sensors are so popular because they reproduce human vision
That's what most people need - making photos that look like what we see.
Replacing RGB subpixels with more different kinds of ...
- 5,069
14
votes
Accepted
Why does flash make a brass subject look grey?
My assumption is that the auto white balance took over.
The image, because you took the photo pretty close is dark everywhere except the brass. If the auto white balance is turned on, the warm tint of ...
- 25.2k
13
votes
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Photoshop's color replacement tool changes to grey (instead of white) — how can I change a grey background to pure white?
The color replacement tool isn't working for you because its default mode is "Color", which changes hue and saturation, but not luminosity (brightness/value). That's why you get the blue or the gray→...
- 143k
13
votes
Why do we use RGB instead of wavelengths to represent colours?
The reason cameras and displays work in RGB is because our retinas work that way.
Since our eyes encode colors with those components (RGB), it is a very convenient system (although certainly not the ...
- 231
12
votes
What is the difference between HSV and CIE-Lab color space?
A perceptual uniform color space ensures that the difference between two colors (as perceived by the human eye). It is proportional to the Euclidian distance within the given color space.
You may ...
- 221
12
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What would happen if a camera used entirely different primary colors?
Color photography is indeed based on the tri-color theory. The world saw the first color picture in 1861 made using red, green, and blue filters by James Clark Maxwell. Today’s color photography is ...
- 39.5k
12
votes
Why do we use RGB instead of wavelengths to represent colours?
An attempt to answer simply:
We cannot practically capture enough information to store a complete breakdown, frequency by frequency, of all the different wavelengths of light present, even just ...
- 13.6k
12
votes
Accepted
Why do we use RGB instead of wavelengths to represent colours?
I think there are some misconceptions in prior answers, so here's what I think is true. Reference: Noboru Ohta and Alan R. Robertson, Colorimetry: Fundamentals and Applications (2005).
A light ...
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10
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What would happen if a camera used entirely different primary colors?
Is this already being done?
Sure. The Hubble Space Telescope senses the near IR, visible, and near UV spectrum. Any images you see from Hubble that contain information outside of the visible ...
- 33.2k
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