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**Ali Abbass** · 06-17-2023, 12:00 AM

The Art of Photography... Principles and Curriculum Lesson -32-
Color capture -4- Dealing with filters

In black and white photography, we use filters to either lighten or darken the gray tones produced by a color in a negative or a black and white print. As for color photography, the use of filters is more complicated because the color of the filter will affect every color in the print or slide. You cannot but use a yellow filter to darken a blue sky:
This is because the yellow filter will affect all colors. However, if used properly, as detailed below, the filters can prove very effective under very different color conditions.
Let's explore the main uses one by one.
Conversion filters:
Probably the most widely used filters in color photography are conversion filters that make you able to use daylight film in tungsten light or tungsten film in daylight The benefit of this is that you don't have to change the language of a partially used film if you change the light source, as well instead Those who carry two types of films can usually carry only one type, Nour Nahar film - and use a conversion filter when tungsten is the light source.
Let's see how this happens in practice by comparing some results.
What would happen if I used daylight-balanced film when capturing a Tugentsen-lit scene? .. look at the pictures .
Photo -1 - of the movie Nour Nahar, which was projected into Nour Nahar. Accurately reproduce natural colors.
And the picture - 2 - of the film Nour Nahar was improperly exposed under tungsten light - note how the colors took a golden-red hue that does not accurately represent the original colors. The picture is 30. It displays the result if you used a conversion filter when capturing Noor Nahar film in Noor Tungsten. What is the specific filter that you should use.. Refer to the instructions slide that the production company attached with the film. Typically.
If your light source is 3400 (K), you use a filter (80B). And if it is 3200 (K) - use (80A).

Now let's see how the tungsten balance film interacts with different light sources. In the picture «4» we see that the natural colors were accurately reproduced, not the tungsten - it is a reflection film in which it was used when a class (B) color film was used with tungsten light as a source - compare this with the picture 50 If you want to use tungsten film with daylight or “strobe” as a light source, you can do that by using a transformation filter, which is (85B) in typical terms, and the result is the image “ 6 »- Compare picture -6 - with picture -4- », what is the accuracy of color representation? ? Again, it's very good, but it's not typical, as we've already noted. With color negative film, you can adjust the colors more when making the print, which you cannot with color reflection film.
We mention here that all filters absorb some light. The darker the filter, the more light it will absorb, and you may have to compensate for this loss of light by widening the aperture.
How wide is it? ..
This depends on the particular candidate. And the instructions attached to the filter tell you about the filter factor - it is a number that guides you to set up the normal exposure - this means that you open one stop - and if the factor is -3- you open a pause and a half, and for the factor -4- you open and turn and so forth.
Do you have to make these adjustments if you're using an SLR camera with a through-the-lens viewfinder? . No, with the exception of extreme cases, your meter will compensate automatically.

- Illuminator and heating filters:
When the solar rays filter through a cloudy or misty layer, they are more blue than open solar rays, and the blue tinge may be ugly on the color gradients of the face in particular, knowing that on a sunny day, the light comes even in the open shade, and it has a blue tinge. Shaded areas tend to be blue as well. And even corrected for this blue tinge. Use a light filter (A1 Skylight). Then, as you learned earlier about black and white film, you can leave an (A1) filter on your lens as a general-purpose cap and lens. Its removal of a small amount of blue is acceptable in color images regardless of the light source. Add to your information that the filter (81A) is in fact a very pale fuchsia filter equivalent to (CC025M).

Pictures taken in open shade may need more blue correction than even the A1 can provide. In such a case, use a heating filter such as (81A), and for a larger correction, try (85C).
Distant mountains and aerial scenes are also improved using the (A1) filter because they tend to be visualized as blue. Shades of blue appear in images of snowy scenes in particular. And (A1) can help correct this, and (85C) will once again provide a larger correction.

Mixed light filters:
When you shoot with color reflection film, you will often encounter circumstances in which the color source does not quite match any of the available film types. For example, in an outdoor arena for sports games, a circus, or a musical performance, the lighting will often be a mixture of tungsten light in the 3000 (k°) range and carbon arc directional lights in the th range. (6000 K°).
So what do you use, Noor Nahar film or Tungsten film?
The law that you have to act upon is: when you have to compromise in the field of balance
colour, do it on the warm side. In the case of our aforementioned arena, if you use tungsten film, the carbon arc lights will produce a “cold” blue hue, and if you use daylight film, the tungsten lights will impart a red and warm color hue, so work with daylight film.

This law becomes its distinctive value when it comes to the color gradations of the skin. We are more willing to accept skin tones that tend towards the red color, which indicates that the subject is healthy and well, compared to our willingness to accept skin tones that tend towards the blue color, which suggests disease and death.

Polarizing filters:
In previous lessons, we discussed the ability of a polarizing filter to reduce polarized light; An example of this is its use to darken a blue sky in a black and white print. Since the polarizing filter is practically colorless, it can be used with colored film for similar purposes.
The blue of the sky can be softened using a polarizing filter without affecting the other colors in the image. This makes you able to make the clouds stand out in prints or colorful slides.

Also, when photographing a landscape, you may find that colors may stand out in this scene with the use of a polarizing filter. The polarizing filter may improve the colors of the different layers in the rock formations. The reason for this is that much of the light reflected from the rocks is polarized and originally reflected from the sky. Such polarized reflection tends to decrease the saturation of the colors, and by removing this polarized light, you increase the saturation of the colors on the rocky surfaces. Thus, believing in more dramatic representation of colors.
As with black and white film, a polarizing filter can also be used with color film to reduce glare and reflections when shooting through glass or water. These applications have a very great value, as we mentioned earlier.
Hence, and because of the wide range of applications that we mentioned above, we recommend that you have a polarizing filter as part of your regular accessories repertoire.

Color Compensation (CC) Filters:
Kodak produces a wide variety of filters with which you can filter each color separately. These color compensation (CC) filters let you make minor or major adjustments to get accurate results under any type of lighting. It comes in six different colours:
green (G).
Blue (B).
red (R).
Dark blue (C).
Fuchini (M).
yellow ( Y ) .
Each of these six colors has a wide range of strengths indicated by a number - the higher this number, the deeper the strength of the color - and it ranges from (CC025) the weakest to (CC50) the strongest, and (CC025) is a very weak candidate, equating to half the strength of filter (CC05), and 1/20 power (CC50). For example, (CC05Y) is a yellow filter with a strength of (05), its strength is equal to a quarter of the strength of a (CC20Y) filter, and (CC10R) is a red filter that is equal to one-third of the strength of (CC3OR), while (CCOSB) is a blue filter that is equal to one-tenth of the strength of (CC50B). It's a simple math problem.
But when to use these CC filters. ? . In any circumstance where you want to modify the print's color or transparency.

A common use of CC filters is to use them to adjust the color mixture specific to sunlight at different times of the day. Although we referred to the sun's rays as (K5500), this is only an approximate value for a clear sky from ten in the morning until two in the afternoon, approximately. And you know very well that the rays of the sun at dawn and dusk are much redder than they are at midday and anything photographed under these rays of the sun, which is redder, will take on a redder appearance. You may find, for example, that the color gradients of the face that you photograph in the light of the setting sun will appear very red, to adjust that, you use a complementary filter for that color that you want to lighten, and the color that you want to lighten here is red, and the complement to it is dark blue (Cyan) - see the color wheel, and this is how you use a filter Dark blue to reduce the red color. As for the strength of the filter that you use, it depends on how much red you want to remove. If you want to remove a lot of redness, you use (CC20C) or another stronger one. To remove less redness, use (CC10C) or weaker.
Note also that you can mix filters to achieve a subtle color shift, but you should always use the smallest number of filters needed to achieve your result since each filter affects sharpness, contrast, and can cause glare.

**Ali Abbass** · 06-17-2023, 12:03 AM

How Professionals Use CC Filters:
When you're working as a professional, accurate colors can be extremely important. This means that the professional often has to exaggerate his accuracy and care to avoid color shifts that can come as a result of a different number of factors.
These factors include the type of light source and the type of film. And the specific paste from which the film is made, there may be a paste from which the Ectachrome film is made, for example, that does not resemble another paste completely, and the colors can change because of the presence of dust on the lens or some color smear on the glass of this lens, exposure, and acidification, because of these Parameters are all variables and professionals usually try to come up with standards for as many of them as possible. They will try to take all studio shots using the same type of lighting. And they use one type of film where they buy a quantity
They will use a single method of development, or they will always send their films to the same laboratory.

However, the most important thing here is that they will experience that when they buy a group of similar films. They will take experimental studio snapshots under their standard conditions, then monitor the resulting transparency to see if there is a shift in color. If they see a shift, they will repeat the test using (CC) filters with a color complementary to the resulting transformation, then try filters with different strengths. Finally, based on these tests, they will adopt Expressive filter (CC) to be used with film paste under similar conditions.

What do these people do while filming outside the studio? ? .
They resort to a few methods, the first of which is that they may use a special light meter that reads the temperature of the light. Based on this reading. They can come to a decision about the CC filters they use.
And the second method is that they will make experimental Polaroid snapshots on site, and if they appear
Polaroid print any unwanted color shift, they will add filters and run the experiments again until they get rid of the shift.
Finally, they will watch for reduced transparencies...if they see a color shift, they may decide to go back and retake the image with a different filter.

Should you use CC filters now?
Now, before you let this intricate detail panic, know that you don't have to bore yourself with these workflows at the current stage of your training. In the first place, simple color shifts won't ruin most of your photos the way a pro taking a picture of a picky client might. Or for publication in a magazine or book. On the other hand, some color shifts may actually be useful. An example of this is that the red tint in subjects that are imagined around the time of dawn or sunset does not necessarily face objections. This is because the red hue gives a warmer color gradient to many images, and the luminance is less contrast.
Many pictures look better in such lighting. In fact, many professionals look to the morning and late afternoon as the typical parts of the day.
Color temperature meters:
Color temperature meters measure the relative amounts of the different colors of light in a certain Sony setting. The meters are very complex, expensive and easy to break devices.

Photographers use them to determine the exact filter needed to get the best color representation - color temperature meters work best - they are called trichromatic meters. To read the amount of red, blue and green lights present in an optical device. There are other color temperature meters that only measure the amount of red and blue light in a scene. This ignores green, which can create problems when working under fluorescent lights, in particular.
This, and the color temperature meter works, in a way very similar to the way the light meter works, but it only indicates the relative amount of each light color in the scene, and after taking a light reading, as is the case with other types of meters, the photographer makes a comparison between the information indicated by a moving needle and a set of scales which then indicate the correct color compensation or optical balance filters.
This kind of accurate information is not typical for most types of work in still photography, and color temperature meters are used most often by cinematographers who want to get a precise balance. For those who often have to mix artificial illumination with daylight in one scene, for such complex circumstances, the use of a color temperature counter is necessary.
As for at this stage of your studies, you should only notice that different mixtures of different light colors may exist at different times in the same day, or under many different types of artificial light, and there is no meter that will measure these different contents of light.

To light fluorescent filters:
Fluorescent lighting presents a dilemma of another kind. While there are different types of fluorescent lamps ranging from warm white, and . cold white, and . Daylight - all of them lack the warm colors of red, orange and yellow - while the cold green colors are available. This might suggest that Nour al-Nahar can be used, but that is not the case. This is because the use of daylight film under fluorescent lights produces a greenish tint, which comes very ugly in the color gradations on the skin. As for the tungsten film, Faso.

Let's see what happens when you take tungsten film under light. fluorescent. Photo 10. It was photographed using tungsten film under tungsten light. In picture -2-, we see what happens when we use the same tungsten film, but we turn into light, a fluorescent one. . The yellow background turned green: the model's pink cheeks were now ghostly white with a greenish tinge. As for the picture -3-, we have used a filter called (FLB) designed for class (B) tungsten film under fluorescent light. As you can see, the correction is not typical, but we got a huge improvement.

Let's see what happens to the movie Daylight Now under fluorescent light. Photo 40 was photographed under fluorescent light using daylight film without a filter - compare it with photo 10 and you will see a slight shift towards green, as the cheeks have lost their pink color and the hair has lost its reddish tinge. However, we want to add the red color in order to restore the correct color gradient, and the picture -5- shows what happens if we use the (FLD) filter designed for a daylight film under fluorescent lighting. We now have more red than we should, so what do we do? ? .

The solution is to use CC filters with Nour Nahar film. The exact filters that should be used depend on the color mixture of the fluorescent lamps in question.

Try the following combination as a starting point:
Use a filter (5M) pale fuchsia with a filter (20B) light blue. Putting one on top of the other at the front of the lens. This combination will reduce the green.
And test this filter either on Polaroid test prints or on preserved slides. If the image persists in appearing too green, you can try stronger filters such as (10M) and (30B). If the image is too red, try a weaker mixture, such as (5M) and (10B). Whatever the case, consult the information that came with the film to see if the producing company recommends mixtures for other filters.
Finally, and in picture -6- you see what happens if you use (5M30B) as your mixture.

Density filters:
As mentioned in our explanation of filters, density filters enable you to reduce the amount of light in a scene when it is too strong, for example in a beach scene where you want to use a wide aperture to achieve optional focus, and since density filters do not change individual colors, It becomes possible to use to achieve this purpose with color film as with black and white film.

Film care:
Compared to a black and white movie. You find the colored film, which is more susceptible to damage, even due to improper care. The same laws generally apply here. But pay more attention to the color film.

As noted above, film referred to as professional should be refrigerated before and after exposure. This is not a bad idea even with general purpose film, especially when you don't expect to use the film quickly or if it is close to its expiration date. However, when you put the film in the fridge or freezer, make sure that it is kept inside something that protects it from moisture. It should be noted here that the unopened film packages are sealed against moisture. As for the opened packages, they should be placed inside sealed plastic containers or nylon bags: then in another one, then in an airtight container as well.
Then when taking the film out of the refrigerator to use it. Let it come to room temperature before opening its package. This requires at least an hour and a half for the refrigerator, and three hours for the refrigerator.
This, and whether or not you cool your film, you still have to avoid extreme heat or humidity. Also, avoid examining x-ray films when traveling by plane, whenever possible. Avoid using the film after its expiry date. Then work on developing the film as quickly as possible after exposure ⏹

Next lesson
Artificial light - 1 -
Equipment and experiments for amateurs

فن التصوير .. المباديء والمنهاج الدرس -٣٢- الالتقاط بالألوان -٤- التعامل بالمرشحات

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