256 gradations. Setting the color display
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Bit depth or color depth of a digital image is the number of binary digits (bits) used to encode the color of a single pixel.
It is necessary to distinguish between terms bits per channel(bpc – bits per channel) and bits per pixel(bpp – bits per pixel). The bit depth for each of the individual color channels is measured in bits per channel, while the sum of the bits everyone channels is expressed in bits per pixel. For example, an image in the Truecolor palette has a bit depth of 8 bits per channel, which is equivalent to 24 bits per pixel, because the color of each pixel is described by three color channels: red, green and blue (RGB model).
For an image encoded in a RAW file, the number of bits per channel is the same as the number of bits per pixel, because before interpolation, each pixel obtained using a matrix with a Bayer color filter array contains information about only one of the three primary colors.
In digital photography, it is common to describe bit depth primarily in terms of bits per channel, and therefore, when talking about bit depth, I will mean exclusively bits per channel, unless explicitly stated otherwise.
Bit depth determines the maximum number of shades that can be present in the color palette of a given image. For example, an 8-bit black and white image can contain up to 2 8 =256 shades of gray. A color 8-bit image can contain 256 gradations for each of the three channels (RGB), i.e. total 2 8x3 =16777216 unique combinations or color shades.
High bit depth is especially important for correctly displaying smooth tonal or color transitions. Any gradient in a digital image is not a continuous change in tone, but is a stepwise sequence of discrete color values. A large number of gradations creates the illusion of a smooth transition. If there are too few halftones, the gradation is visible to the naked eye and the image loses its realism. The effect of causing visually distinct color jumps in areas of the image that originally contained smooth gradients is called posterization(from the English poster - poster), since a photograph that lacks halftones becomes like a poster printed using a limited number of colors.
Bit depth in real life
To clearly illustrate the material presented above, I will take one of my Carpathian landscapes and show you how it would look with different depths. Remember that increasing the bit depth by 1 bit means doubling the number of shades in the image palette.
1 bit – 2 shades.
1 bit allows you to encode only two colors. In our case it is black and white.
2 bits – 4 shades.
With the advent of halftones, the image ceases to be just a set of silhouettes, but still looks quite abstract.
3 bits – 8 shades.
The details of the foreground are already visible. The striped sky is a good example of posterization.
4 bits – 16 shades.
Details begin to appear on the mountain slopes. In the foreground, the posterization is almost invisible, but the sky remains striped.
5 bits – 32 shades.
Obviously, low contrast areas that require a lot of close midtones to display are the ones that suffer the most from posterization.
6 bit – 64 shades.
The mountains are almost fine, but the sky still looks stepped, especially closer to the corners of the frame.
7 bit – 128 shades.
I have nothing to complain about - all the gradients look smooth.
8 bit – 256 shades.
And here you have the original 8-bit photo. 8 bits are quite enough for realistic transmission of any tonal transitions. On most monitors you won't notice a difference between 7 and 8 bits, so even 8 bits may seem overkill. But still, the standard for high-quality digital images is precisely 8 bits per channel, in order to cover the ability of the human eye to distinguish color gradations with a guaranteed margin.
But if 8 bits are enough for realistic color reproduction, then why might a bit depth greater than 8 be needed? And where does all this noise about the need to save photos at 16 bits come from? The fact is that 8 bits are enough to store and display a photograph, but not to process it.
When editing a digital image, tonal ranges can be both compressed and stretched, causing values to be continually discarded or rounded, and eventually the number of midtones can fall below what is needed to render tonal transitions smoothly. Visually, this is manifested in the appearance of the same posterization and other artifacts that hurt the eyes. For example, brightening the shadows by two stops stretches the brightness range by a factor of four, meaning that edited areas of an 8-bit photo will look as if they were taken from a 6-bit image, where the shading is very noticeable. Now imagine that we are working with a 16-bit image. 16 bits per channel means 2 16 = 65535 color gradations. Those. we can freely throw out most of the midtones and still get tonal transitions that are theoretically smoother than in the original 8-bit image. The information contained in 16 bits is redundant, but it is this redundancy that allows you to carry out the most daring manipulations with a photograph without visible consequences for image quality.
12 or 14? 8 or 16?
Typically, a photographer is faced with the need to decide on the bit depth of a photograph in three cases: when choosing the bit depth of a RAW file in the camera settings (12 or 14 bits); when converting a RAW file to TIFF or PSD for subsequent processing (8 or 16 bits) and when saving the finished photo for an archive (8 or 16 bits).
Shooting in RAW
If your camera allows you to choose the bit depth of the RAW file, then I definitely recommend that you prefer the maximum value. Usually you have to choose between 12 and 14 bits. The extra two bits will only slightly increase the size of your files, but it will give you more freedom when editing them. 12 bits allow you to encode 4096 brightness levels, while 14 bits allow you to encode 16384 levels, i.e. four times more. Due to the fact that I carry out the most important and intensive transformations of the image precisely at the processing stage in the RAW converter, I would not want to sacrifice a single bit of information at this critical stage for future photography.
Convert to TIFF
The most controversial stage is the moment of converting the edited RAW file into 8- or 16-bit TIFF for further processing in Photoshop. Quite a few photographers will advise you to convert exclusively to 16-bit TIFF, and they will be right, but only if you are going to do deep and comprehensive processing in Photoshop. How often do you do this? Personally, I don’t. I do all the fundamental transformations in a RAW converter with a 14-bit non-interpolated file, and use Photoshop only for polishing the details. For such little things as spot retouching, selective lightening and darkening, resizing and sharpening, 8 bits are usually sufficient. If I see that a photo needs aggressive processing (we're not talking about collages or HDR), it means that I made a serious mistake in the RAW file editing stage, and the smartest thing to do would be to go back and fix it instead of rape an innocent TIFF. If the photo contains some delicate gradient that I still want to correct in Photoshop, then I can easily switch to 16-bit mode, carry out all the necessary manipulations there, and then return to 8 bits. The image quality will not be affected.
Storage
To store already processed photos, I prefer to use either 8-bit TIFF or JPEG saved at maximum quality. I am driven by the desire to save disk space. An 8-bit TIFF takes up half the space of a 16-bit one, and a JPEG, which in principle can only be 8-bit, even at maximum quality is about half the size of an 8-bit TIFF. The difference is that JPEG compresses images with lossy data, while TIFF supports lossless compression using the LZW algorithm. I don't need 16 bits in the final image because I'm not going to edit it anymore, otherwise it simply wouldn't be final. Some little thing can be easily corrected in an 8-bit file (even if it’s a JPEG), but if I need to do global color correction or change the contrast, then I’d rather turn to the original RAW file than torture an already converted photo, which even in the 16-bit version it does not contain all the information necessary for such conversions.
Practice
This photo was taken in a larch grove near my home and converted using Adobe Camera Raw. Opening the RAW file in ACR, I will enter an exposure compensation of -4 EV, thereby simulating 4 stops of underexposure. Of course, no one in their right mind makes such mistakes when editing RAW files, but we need to use a single variable to achieve a perfectly mediocre conversion, which we will then try to correct in Photoshop. I save the fairly darkened image twice in TIFF format: one file with a bit depth of 16 bits per channel, the other - 8.
At this stage, both images look identically black and are indistinguishable from each other, so I am only showing one of them.
The difference between 8 and 16 bits becomes noticeable only after we try to brighten photographs, while stretching the brightness range. To do this I will use levels (Ctrl/Cmd+L).
The histogram shows that all the tones of the image are concentrated in a narrow peak, pressed against the left edge of the window. To brighten the image, it is necessary to cut off the empty right side of the histogram, i.e. change the white point value. Taking the right input levels slider (the white point), I pull it close to the right edge of the flattened histogram, thereby giving the command to distribute all gradations of brightness between the untouched black point and the newly designated (15 instead of 255) white point. Having performed this operation on both files, we will compare the results.
Even at this scale, 8-bit photography looks grainier. Let's increase it to 100%.
16 bits after brightening
8 bits after lightening
The 16-bit image is indistinguishable from the original, while the 8-bit image is severely degraded. If we were dealing with real underexposure, the situation would be even sadder.
Obviously, such intensive transformations as brightening a photo by 4 stops are really better done on a 16-bit file. The practical significance of this thesis depends on how often you have to correct such a marriage? If often, then you're probably doing something wrong.
Now let's imagine that I saved a photo as an 8-bit TIFF, as usual, but then suddenly decided to make some radical changes to it, and all my backup RAW files were stolen by aliens.
To simulate destructive but potentially reversible editing, let's look again at levels.
I enter 120 and 135 into the Output Levels cells. Now, instead of the available 256 gradations of brightness (from 0 to 255), useful information will only occupy 16 gradations (from 120 to 135).
The photo predictably turned grey. The image is still there, just the contrast has decreased by 16 times. Let's try to correct what we have done, for which we will again apply the levels to the long-suffering photograph, but with new parameters.
Now I changed the Input Levels to 120 and 135, i.e. moved the black and white points to the edges of the histogram to stretch it over the entire brightness range.
The contrast has been restored, but the posterization is noticeable even on a small scale. Let's increase it to 100%.
The photo is hopelessly damaged. The 16 halftones remaining after crazy editing are clearly not enough for an at least somewhat realistic scene. Doesn't this mean that 8 bits are really of no use? Don’t rush to jump to conclusions—the decisive experiment is yet to come.
Let's return again to the untouched 8-bit file and transfer it to 16-bit mode (Image>Mode>16 Bits/Channel), after which we will repeat the entire procedure of desecrating the photo, according to the protocol described above. After the contrast has been barbarically destroyed and then restored again, we will transfer the image back to 8-bit mode.
Is everything alright? What if we increase it?
Flawless. No posterization. All operations with levels took place in 16-bit mode, which means that even after reducing the brightness range by 16 times, we were left with 4096 gradations of brightness, which was more than enough to restore the photo.
In other words, if you have to do important editing of an 8-bit photo, turn it into 16-bit and work as if nothing had happened. If even such absurd manipulations can be carried out with an image without fear of consequences for its quality, then even more so it will calmly survive the expedient processing to which you can actually subject it.
Thank you for your attention!
Vasily A.
Post scriptum
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Evgeny Kuznetsov
I have repeatedly met people who believe that the higher the screen resolution when printing graphic images, the higher the output quality of the publication. In this article I would like to shed a little light on this, since the issue is quite non-trivial and requires discussion :).
First, let's define the concepts. In this article I will use several terms, understanding the meaning of which is necessary for the correct perception of the article’s materials.
dpi - dots per inch - resolution that determines the number of microdots of a particular output device (be it a printer or phototypesetting machine) per unit of length (usually per inch). In fact, this parameter determines the size of the minimum dot that can be printed. The higher this parameter, the correspondingly smaller the size of the minimum point can be. The usual value of this parameter is from 600-800 to 2400-2540 or more dpi.
lpi - lineature - the number of raster dots per inch - a parameter that determines the density of raster lines per unit length (this is also usually a linear inch) in the original after it has undergone the screening process. This resolution should be significantly less than the dpi resolution (why - described later in this article), and is usually 100, 133, 150, 175 or 200 lpi. That is, the raster dot is usually much larger than the minimum dot that can be reproduced on a given device.
Gradation is a shade of the same color. For example, the term "grayscale" can mean any color from black to white, such as 50 percent gray.
Well, now let’s try to understand everything in detail and thoroughly.
Probably, each of you has seen and visually compared for yourself images printed on newsprint and images printed in albums on high-quality coated or glossy paper. The first thing that catches your eye when viewing them (at least what catches your eye :) is the use of different sizes of raster dots in printing. When printing newspaper products, low lineature values are usually used (less than 100, 100, or 133 lines per inch), and when producing higher-quality prints, correspondingly higher values are used (150, 175 or more). Depending on the properties of the paper, the quality of the printing press and some other factors, there are optimal parameters that vary from one printing house to another (depending on the equipment they use), but in general, the higher the lineature, the more image detail can be convey in print. The test image below shows a screen simulation using different lineatures.
Rice. 1a. Example of screening using 60 lpi lineature
Rice. 1b. Example of screening using 100 lpi lineature
Rice. 1st century Example of screening using 150 lpi lineature
Rice. 1 year Example of screening using 200 lpi lineature
However, printing with higher lineatures imposes a number of requirements on the paper, the printing press, and even on the resolution of the phototypesetting machine, therefore, the great importance of lineatures is not always a good thing. Usually, too high a lineature and, accordingly, too small halftone dots create the effect of a more “contrast” print - the light areas of the image become lighter (usually due to problems with copying processes), and the dark ones merge into dies where shadow details disappear. As a result, the image begins to suffer from a lack of shades. Within the framework of this article, only the influence of the resolution of a phototypesetting machine on the quality of transmission of raster dots, and, consequently, the shades of the image, is considered. That is, we consider what is determined at the last stage of pre-press preparation - at photo output.
The resolution of a phototypesetting machine (or other output device) is a parameter that determines the maximum possible number of microdots reproduced per unit length. Typically, the higher this value, the better - accordingly, the more dots that can be printed, the finer the shapes of the elements can be reproduced. In this case, the subtlety of the form means the correctness and smoothness of the contours of the raster dot, and their display with minimal discreteness. The image below shows highly enlarged 30% density elliptical dots with 45 degree screen rotation (black ink), taken from a real image that was screened at 150 lines per inch, using various (indicated in the image captions) resolutions phototypesetting machine.
Rice. 2a. Shape of a raster dot at a resolution of 600 dpi
Rice. 2b. Shape of a raster dot at a resolution of 1200 dpi
Rice. 2c. Shape of a raster dot at a resolution of 1800 dpi
Rice. 2g. Shape of a raster dot at a resolution of 2400 dpi
From the figures it is clear that the shape and correctness of the outlines of a single raster dot depends entirely on the output resolution of the phototypesetting machine (or another output device, the same printer). Well, the better the quality of the raster dot is reproduced, the greater the number of elements (microdots) it is built with, the greater the number of colors or gradations it can convey, because the color in any place on the print depends mainly on the size of the raster dot (and a little on the degree of whiteness of the paper and on the presence or absence of varnish. And of course, also on the printing conditions). Mathematically, the formula for calculating the number of gradations possible for given values of lineature and resolution in dpi is written as follows:
The formula is extremely simple and understandable, and one is added to the total number of gradations to take into account a color in which there are no halftone dots (i.e., the color of the paper is usually white). By doing some simple calculations, we can determine how the resolution of the phototypesetting machine determines the output number of gradations at the output. Below is a table for four different phototypesetter resolutions and output lineatures. At the same time, it is indicated what the maximum number of gradations can be obtained under given conditions.
| Output lineature, lpi | Available number of gradations, VOT(Variables of Tone) | |||
| 1200 | 2400 | 3600 | 4800 | |
| 60 | 400 | 1600 | 3600 | 6400 |
| 80 | 225 | 900 | 2000 | 3600 |
| 100 | 140 | 550 | 1200 | 2300 |
| 120 | 100 | 400 | 900 | 1600 |
| 133 | 80 | 320 | 730 | 1300 |
| 150 | 65 | 256 | 570 | 1025 |
| 175 | 48 | 180 | 420 | 750 |
| 200 | 37 | 145 | 325 | 577 |
| 225 | 29 | 110 | 256 | 450 |
| 250 | 24 | 93 | 205 | 360 |
In this case, it is assumed that the resolution of the phototypesetting device (printer) in both directions of film exposure (printing) is the same. If the resolutions are different, the root mean square of both resolutions is calculated and substituted into the above formula. The table shows that when printing using the same resolution, in general, an increase in the lineature leads to significant losses in the transmission of color shades, which can be observed in practice when printing with high lineatures with not high enough resolution.
How many gradations can be considered sufficient? Most raster files use a color depth per color channel of 8 bits per image pixel. If there are three channels, as in the additive RGB model, then the total color depth will be 24 bits per pixel, and if four channels are used, as in the subtractive CMYK model, then the color depth of all of them will be 32 bits. Thus, one pixel in one color channel can have one of 2 to the 8th power (256) states that determine its color. Ideally, the output device should provide the same 256 brightness levels, or, in relation to printing, 256 different states of raster dots (no more). This, of course, does not always happen, and no device, as a rule, reproduces all 256 gradations. But the operating parameters of the output resolution in dpi should always be specified “with a margin”, which will ensure a sufficient level of quality and reduce the impact of various errors on print quality. Thus, the optimal dpi resolution for printing with 150th lineature is 2400 dpi, resolution for lineatures 175 and 200, as well as 225 - 3600 dpi. Specifying large resolution values to obtain an even larger number of gradations is not only useless (since you will not be able to visually distinguish such a large number of shades; the value of 256 is already the “ceiling” of common sense, and above it fanaticism begins), but also harmful, since At the same time, the processor time required for printing and processing printer data output at such a high resolution increases significantly. In fairly rare cases, for some projects you can use screen line values above 225 lines per inch, and use a resolution of 4800 dpi for this. This resolution value will provide the required number of gradations. Do not forget also that printing with high lineatures is also fraught with big problems with copying printing forms, where a raster that is too “thin” can simply be “copied”, i.e. light areas of the form may be completely discolored; Don't forget also about dark areas that can turn into solids if the gap between the raster dots is too small. Don’t forget about dot gain, which particularly affects high-lineature works.
| Type of material to be printed on | Lineature | Optimal resolution |
| lpi | dpi | |
| Low quality newsprint | 80 | up to 1200 |
| Newsprint | 100 | 1600-2400 |
| Newsprint and offset paper | 133 | 2200-2540 |
| High-quality offset, coated paper | 150 | 2540-2800 |
| Coated paper | 175 | 2800-3200 |
| High quality coated papers | 200 | 3200-3600 and more |
This will bring up a menu showing all the color modes Photoshop can use. The current mode will have a checkmark on the left:
So how does Grayscale change a photo from color to black and white? Unlike the RGB color mode, which can reproduce millions (even billions) of colors, Grayscale does not reproduce colors at all. It can only reproduce black, white, and every shade of gray in between, and nothing more. When we convert a color photo to black and white using this mode, Photoshop is essentially only approximating what the black and white version of the image should look like using the original color information.
To convert an image to B&W using this mode, simply click on it in the list of color modes:
A small dialog box will open in Photoshop asking if we really want to discard the color information. If you are using version CS3 and higher (here I am using CS6), the program will recommend that you use the conversion using the "Black and White" correction, as it has more settings, but because... We are interested in the “Grayscale” mode here, click on the left button “Cancel” (In the English version, this button is on the right and is called “Discard”, the left button is “Cancel”).
Photoshop instantly discards the photo's color information and leaves us with its own version of the black and white image:
This is certainly a b/w image option, but is it any good? It seems like not quite. The light areas aren't light enough, the dark areas aren't dark enough, and overall it looks pretty dull and uninteresting. To make matters worse, we could control the transformation. Photoshop simply stripped the image of color and that's it. But, nevertheless, it was done quickly.
Therefore, this option is suitable if we are creating some kind of special effect and need to quickly remove color from a photo without worrying about the quality of the resulting image.
If we look again at the information at the top of the document window, we see that the color mode is now listed as "Gray", short for "Gray". :
And if we now look in the Channels palette, we'll see that the original red, green, and blue channels have disappeared, meaning that Photoshop no longer has any way of reproducing color in an image. All we have now is just one gray channel, giving a black and white version:
Please note that if you save and close the image at this point, the color information will be lost forever. To quickly switch the mode back to RGB, press the Ctrl+Z key combination.
Let's summarize.
We found that most images are in RGB color mode by default. To convert a color photo to black and white using the "Grayscale" mode, go to the main item Image --> Mode --> Grayscale (Image --> Mode --> Grayscale), after which a window will open in which click the left button “Cancel” (In the English version, this button is on the right and is called “Discard”).
This is a quick and convenient way to remove colors from a photo when the quality of the resulting image is not important.
In the next article we will look at another way to convert an image to black and white using Photoshop, this time
The pathology we consider below can be congenital (as a rule) or acquired (much less often) and concerns vision. That is, when color blindness color is perceived differently by a person when compared with others. The perception is abnormal. Depending on the form of the problem, its symptoms will differ. In any case, with this disease, the ability to perceive one or more colors is lost. To diagnose this type of blindness, the Ishihara test and the FALANT test are used.
In addition, anomaloscopy and Rabkin’s polychromatic table help to identify what’s wrong. As for treatment methods, today there are no specific ways to eliminate color blindness. As part of symptomatic therapy, specialists can offer glasses and lenses with special filters to correct the condition. As an alternative, they also resort to programs and cybernetic devices that allow them to work with color images.
The discovery of color blindness and statistics
In color blindness, the retinal receptors perceive color with disturbances. At the same time, the rest of the organ does not suffer functionally. It is noteworthy that the disease is named after J. Dalton. The English chemist inherited this disease, and he began describing it around 1794. Modern researchers and doctors today say that color blindness most often affects the stronger sex (about 2-8%). Women encounter the problem much less often (about 0.4%).If we consider the prevalence of forms of the disease, it turns out that in 6% of cases, men have deuteranomaly. About 1% may have protanomaly and an even smaller number may have tritanomaly. But the rarest form is considered to be achromatopsia - it occurs in one in 35,000 people. It is noteworthy that the risk of developing this particular type of color blindness increases when closely related marriages occur. For example, on the island of Pingelape (Micronesia) there are entire families with color blindness and all because of the many consanguineous unions.
Color blindness and its causes
As noted above, the problem is associated with a distorted perception of color by the retinal receptors (more precisely, its central part). Typically, the organ has three types of cones, which contain a protein pigment that is sensitive to colors. A certain type of receptor is responsible for the perception of a particular shade. Thanks to receptors that respond to all spectrums of blue, red, green, a person receives color vision.Color blindness as a hereditary anomaly is associated with a mutation on the X chromosome. That is why the disease often affects men whose mothers were so-called gene conductors with pathology. A girl runs the risk of encountering pathology if her father was color blind and her mother was a carrier of a defect at the genetic level. Studies have shown that mutations in more than 19 chromosomes can provoke immunity to flowers. About 56 genes have also been identified, in the presence of which color blindness develops. Congenital pathologies cannot be excluded. For example, cone cell dystrophy can provoke the disease. For some, it's all about Leber's amaurosis or retinitis pigmentosa.
As for acquired color blindness, brain injuries (occipital lobe) play an important role here. Possible tumors (not necessarily malignant). It can negatively affect vision in terms of color perception. It happens that the reason is post-concussion syndrome. In addition, experts call retinal degeneration and the influence of ultraviolet radiation. For some, the problem is caused by age-related macular degeneration. It is worth adding cataracts and diabetic retinopathy to this list. Intoxication or poisoning sometimes provokes temporary color blindness.
Forms of color blindness and their manifestations
From all of the above, it is clear that with color blindness a person cannot distinguish one color from another. At the same time, one or another form of the disease has its own characteristics. For example, with protanopia, red shades are not perceived. But tritanopia is different in that it is impossible to distinguish the blue-violet part of the spectrum. With deuteranopia, green is not differentiated, and with achromatopsia, there is no possibility of color perception at all. That is, the latter sees the world literally in black and white.As experts note, most often we are talking about simpler forms of color blindness, when it is not possible to perceive any one primary color. Then they talk about anomalous trichromacy. It is noteworthy that trichromats with protanomal vision, perceiving yellow, will see more red shades, and deuteranomals will see more green. Protanopes will replace the lost part of the color scheme with blue and green. In deuteranopes, blue and red predominate, while in tritanopes, red is paired with green. Some have red-green blindness.
Methods for diagnosing color vision problems
It was previously mentioned that ophthalmologists use tests (Ishihara, FALANT test) to test vision. Also, as part of the study, polychromatic Rabkin tables may be needed. If necessary, the process is supplemented with an anomaloscopic technique. In particular, the Ishihara color test consists of photographs with images of colored spots. When combined, the spots form a pattern. If a person is color blind, they will lose part of the drawing and will not be able to accurately characterize the image. Also, some cards feature simple geometric symbols and Arabic numerals. It is noteworthy that the background of the figure and the main one differ slightly, so often with an illness you will only be able to see the background. By the way, instead of numbers, children's drawings have been prepared for children. Diagnosis using Rabkin's tables occurs in a similar way.In special cases (for example, if a person gets a job where there are special requirements for color perception), anomaloscopy and the FALANT test are performed. The first method will tell you both about the type of violation and give an idea of the level of brightness and color adaptation. It will be possible to study the influence of age, pressure and air composition and learn how medications affect the functioning of retinal receptors. The technique is necessary to establish standards regarding color differences. With its help, professional suitability in some industries is assessed and treatment results are monitored. But the FALANT test is widely used in the United States when examining future military personnel. A person needs to determine from a certain distance the color that the beacon emits. The glow consists of three, slightly muted colors. It is noted that even with a mild form of color blindness, 30% of men are tested.
According to experts, a congenital disease is often diagnosed late, since a colorblind person names colors based on generally accepted concepts (for example, grass is green, etc.), but not as he actually sees them. If there is a burdened family problem of this kind, you need to be examined by an ophthalmologist as soon as possible and without fail. This is especially important if the disease is secondary, that is, caused by other vision problems - cataracts, diabetic neuropathy, age-related macular degeneration. As a result, myopia may develop as a complication. Retinal dystrophy cannot be ruled out.
It is important to understand that color blindness does not affect the sharpness or narrowing of the field of vision. If there are difficulties of this kind, it means that the problem is some other disease. Additional research is indispensable here. The same applies to acquired forms of color blindness. Since the illness in this case is only a consequence of a deeper problem, it is necessary to eliminate it first. This will protect against the development of complications, for example, in the form of organic changes in the eyeball. Experts recommend undergoing tonometry and ophthalmoscopy every year. Perimetry wouldn't hurt. This list also includes refractometry and biomicroscopy.
Ways to eliminate colorblindness
So far there is no way to get rid of the congenital disease. The same can be said about color blindness caused by pathologies in genes, for example, with Leber amaurosis or cone dystrophy. Tinted filters for glasses have been created to help people. Contact lenses are also offered (today there are about 5 types of corrective lenses). Both should reduce the symptoms of the problem. You can talk about the effectiveness of glasses or lenses if you managed to pass the Ishihara test 100%.For those who work in the color palette, special developments help improve orientation - cybernetic eyes, i-borg, GNOME. The acquired disorder must be dealt with by specialists involved in eliminating the main provoking pathology. In particular, color blindness will disappear if cataracts or brain damage are treated. In any case, the doctors' forecasts are favorable. But, of course, we should not forget that color blindness will one way or another affect a person’s quality of life. For example, the choice of profession will be limited, that is, becoming a doctor, public transport driver or military officer will clearly not be possible. And in Romania and Turkey, people with color blindness don’t even issue a driver’s license.
Finally, in order to protect yourself from encountering the disease discussed in the article, when planning a pregnancy, it is better to consult with a geneticist (especially if the marriage is between relatives or there is color blindness in the family). With progressive cataracts and diabetes mellitus, you should visit an ophthalmologist several times a year.