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📷 | What is “things that should not be photographed” with a smartphone camera?


What is "things that should not be photographed" with a smartphone camera?

If you write the contents roughly
If you really want to shoot, attach a light amount adjustment filter (ND filter).

Speaking of new smartphone products, the performance around the camera is sure to be talked about.Compare the latest model with the model 5 or 6 years ago ... → Continue reading


It is a site "PHILE WEB" (file web) that delivers daily news, reviews, bargain information, etc. on AV / audio / gadgets. First published in 1999.

Wikipedia related words

If there is no explanation, there is no corresponding item on Wikipedia.

Lens filter

Lens filterIs写真,ImageWhen shootingtelescopeWhen observing withlensAttached to the tip, rear end, or middle part of the, to limit the light passing through itColor filterAnd otherOptical filter.

the lightwavelength,Polarized lightIt is controlled by transmission or reflection.There are also filters that add so-called soft effects and striation effects.

Classification by effect

Polarizing filter

Polarized lightA filter (PL filter, PL: Polarized Light) is a filter that has the effect of strongly attenuating components that have linearly polarized light in a specific direction, and by rotating it.Surface reflectionYou can make the light from the light stand out or suppress it.For the principle, "Polarized lightSee section.

It is used to remove reflections due to reflections on the water surface and glass, for example, when shooting through glass, such as when shooting exhibits in showcases.Also, in order to remove the reflection of water vapor in the air, the color tone of the blue sky or the leaves, mountain surface, buildings, etc.コ ン ト ラ ス トIt is effective in emphasizing.AlsoRainbowCan be clearly copied or erased.

When used with an ultra-wide-angle lens, the effect may differ at both ends of the screen, making it unnatural.

Circular polarizing filter

The circularly polarized light filter cuts light other than light in a specific polarization direction and converts the transmitted polarized light into circularly polarized light.auto focusIf a linearly polarized polarizing filter is used in a camera, a problem may occur in focusing operation, so a circular polarizing filter is used.
The circular polarizing filter is made by stacking (straight) polarizing filters in order from the subject side.The light incident on the filter first passes through the polarizing filter and becomes linearly polarized light.When this linearly polarized light passes through the quarter wave plate, a phase difference occurs and it is converted into circularly polarized light.As described above, since the polarizing filter is first passed through, the effects such as usage and reduction of reflected light are the same as those of the above-mentioned polarizing filter.Actually, in order to protect the quarter wave plate and the polarizing filter, one circular polarizing filter is sandwiched between flat glass.
Autofocus mechanismTTL exposure meterforHalf mirrorI have a camera that uses.When a general half mirror is used, there is an oblique light incident on the half mirror inside.The reflectance and transmittance of light areFresnel equationsIt is affected by the polarization direction and the angle of incidence as represented by.Therefore, if a linear polarizing filter is used, the half mirror cannot be operated as intended. A "Circular PL filter" can avoid such problems.There are also half mirrors that are less affected by this, such as the pinhole mirror used by Nikon F3.

Sharp cut (SC) filter

Cuts light with a wavelength shorter than a certain wavelength.The name is displayed as "SC" + "cut wavelength (nm) / 10"[1].

UV (ultraviolet absorption) filter

UV (Ultra Violet) filterUVIt is a filter that cuts.Although it is said to be colorless and transparent, it has an extremely pale yellow (or yellow-gray) color that cannot be seen, and this ultra-pale yellow (or ultra-light yellow-gray) plays a role in absorbing ultraviolet rays, and depending on its intensity, ultraviolet rays Absorption amount changes.
Since the former dry plates and films are too sensitive to ultraviolet rays and blue light, the distant view is not as clear as it looks, and it looks like white blur and haze or fog.[2]Therefore, I used a very light yellow (or very light yellow gray) filter or screen to capture the scenery clearly.The successor is the UV filter.
This is used when ultraviolet rays are reflected and scattered by dust in the atmosphere and the distant view is not clearly captured.Even if it is attached, it does not affect the color reproduction, andExposureDoes not go down.Some people leave it on as a substitute for the lens cover, but it is better to wear it when necessary because dust may adhere to it or defects may enter.
In recent years, the technology of lens coating has advanced and the lens itself has come to block ultraviolet rays, and with the digitization of the camera, the inside of the camera bodyCMOS sensorDevelopment andLow pass filterCoupled with the appearance of cameras equipped with, it is now becoming less used as its original purpose.

The name as a sharp cut filter is SC37 (L37)[3], SC39 (L39)[4]Is this.In addition to this, there are also L38, L40, and L41.

L37, L38 and L39 are difficult to see yellow even when placed on a blank sheet of paper, but L40 can see a faint yellow (or yellow-gray).
L41 has a light purple color and has a function of absorbing a part of ultraviolet rays and blue light, so it is similar to a skylight filter and doubles as a UV filter and a protect filter.

Skylight filter

It is a light russet or light purple filter that has the function of cutting ultraviolet rays and part of blue light (violet, indigo, purple, blue).There are usually two types, "1A" and "1B", and "2B" is more effective.Generally, when shooting with film, the film itself is sensitive to ultraviolet rays and blue light, so the haze of the distant view due to ultraviolet rays is emphasized rather than being perceived by the naked eye, and the subject becomes slightly bluish "blue cover".It is a filter to correct it.It is mainly used for outdoor photography on mountains, the sea, and plateaus in fine weather, and outdoor photography in fine weather (especially when the blue sky is clear).It may also be used to prevent it when shooting in cloudy weather or in the shade where the color temperature is high and it tends to be bluish.Although there are differences depending on the product, the principle isLight OfwavelengthOf which, about 390 nm --It is to cut 410 nm or less.Visible lightIs 380 nm-750 nm, so it cuts visible light of the corresponding wavelength at the same time as ultraviolet rays, that is, bluish (strictly purple) slightly, and reduces the "blue fog" of the subject taken under the blue sky. It is a mechanism.

Since it cuts ultraviolet rays and adjusts the color balance of the subject at the same time, it has become popular as color films have become popular, but it has become obsolete due to the digitization of cameras. UV filters are still used in place of protect filters, but due to the above characteristics, when shooting with a digital camera, the image becomes slightly reddish, so it is a substitute. Must not be.Also, even when shooting on film, more red light is transmitted, so overexposure may occur in the reddish part.

Black and white collect filter

Also known as a correct filter, the yellow filter corresponds to this.
Corresponds to Wratten Nos. 6-9, formerly K1, K1'1/2[5], K2, K3, etc., but now Y0 (bright yellow, pale yellow)[6], Y1 (medium yellow), Y2 (yellow), Y3 (dark yellow) are generally used, and Y48 corresponding to JIS standard Y2 is most used, and the larger the number attached, the stronger the effect that can be possessed. ..

The ordinary color-blind dry plate, commonly known as the color-blind dry plate, is insensitive to green, yellow, orange, and red, but is sensitive to ultraviolet rays and blue light (violet, indigo, purple, and blue). Has the drawback of being too sensitive, and there were many obstacles such as the blue sky being crushed white, the distant view becoming hazy and sometimes thick fog, and the shades and shades of the image becoming unnatural.
Therefore, the collect filter was used for the purpose of preventing haze and fog from being applied to the image due to excessive feeling of ultraviolet rays and blue light.
The most drawback of being too sensitive to ultraviolet rays and blue light is that even if the shape shifts from a dry plate to a film pack or roll film, the properties are ortho (feel yellow, not red or orange), orthochromatic (red and orange). Even though it developed into panchromatic (feeling all colors), it continued to hold even though it was alleviated, and the importance of the collect filter did not change.

Like the UV filter, it absorbs ultraviolet rays to cut it, and at the same time it also cuts blue light. For example, by darkening the blue sky a little, white clouds can be clearly projected, and haze and fog can be seen in the distant view. It has the effects of preventing and capturing clearly, increasing contrast, and adjusting the color to match the appearance of light and shade.
However, only Y2 can be expected to have these effects more than enough, and Y0 and Y1 can cut ultraviolet rays because the yellow color is light, but only a little blue light, so even if the image can be made clear, The effects such as contrast and color adjustment are insufficient, while Y3 has these effects and tends to produce an unnatural image.

There is an example of using Y2 regularly instead of the UV filter, but it is better to install it only when necessary to prevent problems such as dust adhesion and flaws.

Other yellow filters include Aero No. 1 (Wratten # 3), Minus Blue (Wratten # 12), G Filter (Wratten # 15), Flavadin (Wratten # 16), Quinoline Yellow (Wratten # 17). XNUMX) exists.
Aero No. 1 is a pale yellow filter that is mainly used for aerial photography and has the function of absorbing ultraviolet rays.
Minus blue is a slightly orange-yellow filter that is mainly used for aerial photography, and as its name suggests, it absorbs ultraviolet rays and blue light, so it can cut haze caused by ultraviolet rays.It is also used to prevent the "blue fog" that occurs when shooting the full moon. Designated filter of "Kodak Aero Ektachrome Infrared".
The G filter is a deep yellow or clear yellowish orange filter that absorbs most of the ultraviolet and blue light.Therefore, the contrast is emphasized, such as the blue sky appearing quite dark.
Flavadin has a function of emphasizing contrast more than G filter, and is a filter exclusively for panchromatic film.
Quinoline Yellow is a filter used for astrophotography, etc., and has the function of transmitting ultraviolet rays and absorbing purple light.

Nowadays, both filters are rarely used in general, and although it is difficult to obtain them in Japan, they can be obtained by private import.

Black and white contrast adjustment filter

By cutting off ultraviolet rays and blue light (violet, indigo, purple, blue, turquoise) and transmitting orange, red, and blue light more, cool colors are darkened, black, warm colors are brightened, and contrast is achieved. It is a filter used to raise it, and is not used regularly.

Orange is represented by "O" or "YA", and red is represented by "R". As with other filters, the larger the number, the stronger the effect.
O56 and YA2 corresponding to JIS standard O2 and R60 corresponding to R2 are used as standard.
In addition, there are O1, YA1, and YA3 for orange, and R0, R1, and R3 for red.

Since it has the effect of increasing the contrast, if a filter with a large number is used, the difference in brightness and shade will become extreme, so it may be treated as a special effect filter due to its properties.

In addition to being able to take pseudo-infrared photographs with YA3, R0, and R1, R2 and R3 are also used for taking infrared photographs using infrared film.

Color matching filter for black and white

It is not a sharp cut filter, but it has similar uses, so I will explain it here.

The color sensitivity of orthomatic dry plates and films is insensitive to red and weak to green, but has the point that it is too sensitive to ultraviolet rays and blue light as well as normal color sensitivity.
Therefore, while the red color appears black like a coal group and the green color appears darker than necessary, the distant view looks like haze, haze, and sometimes fog, and the cool colors are overexposed, and the contrast is high. It was often low.
After that, various efforts were made to solve the problem that red is insensitive, and orthochromatic, which is somewhat less sensitive to red and orange, and panchromatic, which is sensitive to blue to red. , Dry plates and films such as ultra-red oranges that are sensitive to red and infrared rays have appeared, but they all have varying degrees of ultraviolet and blue light, and they still have the point that they are too sensitive. Not only that, panchromatic had even a sensitive property in red, and in each case, there was a point that the green color called "green deficiency" was dull.

The green filter is used for the purpose of correcting them, and has the property of absorbing all of ultraviolet rays and blue light (violet, indigo, purple, blue), about half of red and orange, and supplementing green.
Use light green, yellow-green (PO0, X0, beta, etc.) and green or dark green (PO1, X1, Gamma, etc.) filters to block ultraviolet and blue light and diminish red and orange. By doing so, I adjusted the balance of light and shade and shade.

However, due to the subsequent technological advances, the current panchromatic film has almost the same color sensitivity in all areas of visible light, so the chances of using a green filter are very small.

However, it is not completely obsolete at present, and when taking portraits with black-and-white film, if you want to suppress the redness of the skin and lips and make the shades and shades more natural, or if you want to capture fresh green etc. freshly. In this case, it is used for portrait photography in a forest with abundant green leaves, and light green, yellow-green, green or dark green filters are used according to the subject and the weather.

It also has the function of capturing the landscape more clearly by absorbing ultraviolet rays and blue light, so it may be used as a regular filter instead of the yellow filter.In that case, a light green filter or a yellow-green filter such as PO0 or X0 is mainly used, but it should be noted that the blue sky appears darker than when the yellow filter is used.

Infrared film filter

Infrared film is also sensitive to normal light, so shooting without a filter has no advantage.Therefore, SC600 that cuts light of 60 nm or less[7]The above red filter must be used.

Light pollution cut filter

When taking astrophotographySodium lampEmission spectrum (D1: 589.6 nm and D2: 589.0 nm)Mercury lampIn urban areas such asLight pollutionTo cut.Thin film interferenceThere are many filters that cut light by using, and the wavelength range that can be cut is shifted to the side with a smaller wavelength according to the incident angle of light.Even if the cut band shifts, light pollution can be cut if the emission line falls within the band, so the effect can usually be ignored unless it is a wide-angle lens.

LPS filter

Light Pollution Suppression filter. Also called LPR (Light Pollution Resistance).Since it is a broadband filter, the amount of transmitted light is large and it is difficult to darken.Conventionally, sodium lamps and mercury lamps,Fluorescent lightMainly filters that cut the wavelength range of, but in 2018LEDFilter that cuts the wavelength range of, in 2019AirglowA filter that also cuts has been released.

UHC filter

Ultra-High-Contrast filter.It is a narrow band filter that transmits only a narrow wavelength region including Hβ and OIII rays, and is suitable for photographing nebulae.

CLS filter

City Light Suppression filter.Narrow band filter. It transmits a wider range than the UHC filter.

Color absorption filter

Like a starry night filter, it blocks light pollution by absorbing specific wavelengths.Unlike filters that use thin film interference, it can cut specific wavelengths regardless of the focal length of the lens.

HF glasses

To some extent by cutting the light of mercury lamps and sodium lampsLight pollutionA filter for astronomical photography that can reduce the adverse effects of.

Filter for 103aE

Spectroscopic film"103aE" is a red-black SC640 that cuts light below 64nm.[8]Had to be used, but at the same time light pollution was cut.

Other filters

Moon & SkyGlow filter, Quad BP (BandPass) filter, Nebula Booster filter, O-III filter, H-Alpha filter, etc.

Special effects filter for black and white

This is the dark blue filter, but unlike the yellow, green, orange, and red filters, there is no one dedicated to black-and-white film, and it is one of the three-color separation filters used when making photographic originals of color originals. , Ratten # 47 and corresponding filters are used.

While this filter transmits more ultraviolet rays and blue light, it has the function of absorbing infrared rays, red, orange, and yellow, and weakening green and the like.
Therefore, if you shoot with this filter applied, the blue sky will fly white, the distant view will be covered with strong haze and fog, the warm colors will be black, the contrast will be low, and the perspective will be lost. Becomes flat.
Therefore, it is rarely used for black-and-white photography, and is only used when aiming for specific effects such as applying a strong fog to a distant view, giving a blurry feeling to the entire landscape, or making the skin look brown.

Color enhancement / effect filter

When using a color film, emphasize a specific color or add a specific color.

The sharp cut filter for monochrome film may be used as a color enhancement filter for color, or the CC-M40 may be used to make a fantastic photograph.

ND filter

It is a neutral density filter and has the effect of uniformly reducing the amount of light entering the lens. ND is an abbreviation for Neutral Density, which means neutral to color.By using this, you can open the aperture when shooting,Shutter speedCan be lowered.Shooting outdoors with a bright lens, etc. Even in fine weather, shooting with the back blurred in the open state, shooting the flow of a river like a collection of threads, shooting a busy cityscape with people erased, There are applications such as shooting with special effects due to long exposure.In addition, since the shutter speed cannot be changed during video shooting, overexposure may occur outdoors during the daytime, but overexposure can be prevented by dimming the light by using it as an ND filter.
Some ND filters provide the ND effect only in the center for the purpose of shooting a subject with a large difference in illuminance, or the dimming effect only on one half of the screen.Common ND filters are gray or black, with ND2, ND4, ND8, ND400, etc. depending on the degree of darkness.eclipseな ど(I.e.There are also high-magnification filters such as ND10000 and ND100000, which are mainly used for shooting. For ND2, the amount of light is 1/2, and for ND400, the amount of light is 1/400.
The purpose is to reduce the light without affecting the color reproduction, but some products may affect the color reproduction, and many of the products with particularly high density have a yellow turnip.Generally, it looks black (gray) due to absorption, but some high-magnification products such as those for solar photography also have reflectivity, and such products look silver due to metal deposition.

Variable ND filter (variable ND filter)

The variable ND filter is a filter in which the reduction rate of the amount of light is variable.It is usually composed of two lenses, and the reduction rate is changed by rotating the lens on the subject side.The range of reduction rate varies, but the wide range of ND2-400 and ND2.5-1000 can be changed continuously.Variable ND filterCircular polarizing filterIt is made by facing each other on the front side of.In other words, with variable ND filters, the filters are lined up from the subject side as follows.

   subject-1-Polarizing filter1-Polarizing filter2-4 / 1 wave plate2

"Polarizing filter1-Polarizing filter2It is dimmed according to the relative angle of the polarization direction. 4/1 wave plate1By making the incident light circularly polarized, the light in any polarization direction can be uniformly dimmed by the polarizing filter. 4/1 wave plate2 TheCircular polarizing filterAs described in, it is used to operate ode focus and the like normally. 4/1 wave plate1Because there is a "polarizing filter1-Polarizing filter2Even if the polarization directions are aligned, the variable ND filter cannot be used as a polarizing filter.

Color temperature conversion (LB) filter

The film is a daylight type with a normal color temperature of about 5500K, and a tungsten type with a normal color temperature of about 3200K, and is manufactured to develop natural colors.However, the actual light is diverse, for example, the color temperature is 2000-4000K at sunrise or sunset, the color temperature of light bulbs and flood lamps is low at 2800-3200K, which is reddish, and the light of electronic flash is generally reddish. The color temperature is around 6000K, and in the shade or cloudy weather, the color temperature is as high as around 6500K, which is a bluish light.Color temperature conversion (color temperature conversion) is used to correct the color temperature because it becomes reddish when taken under light with a color temperature lower than the color temperature assumed by the film, and bluish when taken under high color temperature. Light Balancing) filter.

Amber (LB-A) that lowers the color temperature[9]) And raise blue (LB-B[10]).

For example, if the color of the product on the catalog is different from the actual product, it is necessary to correct it to make it the "correct" color, but for example, it is natural that the screen becomes reddish in the sunset scene, so by correcting it It is not always recommended to use it in landscape photography because it will kill the atmosphere of the place, and conversely, it may be emphasized by using LB-A in the setting sun.

Digital camera,Video camera(Camcorder) Built-inWhite balanceFunctions have replaced these, and in recent years they have gradually become obsolete with the spread of digital cameras.

Color correction (CC) filter

Color Compensating filters are used to shoot in the proper color conditions.

For sheet filters, the three primary colors of cyan (CC-C), magenta (CC-M), and yellow (CC-Y), and their complementary colors, red (CC-R), green (CC-G), and blue (CC-B). ), And various concentrations such as 1.25, 2.5, 5, 7.5, 10, 20, 30, 40, 50, etc. are on sale.By combining these according to the measurement result with the color meter, it is possible to correspond to any state.Only the colors and densities that are commonly used in glass filters are on sale.

Digital camera,Video camera(Camcorder) Built-inWhite balanceFunctions have replaced these, and in recent years they have gradually become obsolete with the spread of digital cameras.

Fluorescent lamp (FL-W) filter

If you use a daylight type film and shoot under fluorescent light, it will turn green, but it is used to correct it. A type of CC filter, with individual CC filters CC-M30 or CC-M40M, and in some cases CC-10R or CC-R20, or CC-Y10 or CC-Y20Y to achieve the same effect.

Fluorescent lamps have different colors depending on the manufacturer, type, and usage time, so a color meter and CC filter are required for strict correction.

TV screen shooting (TV-CC) filter

A filter used when shooting TV screens using daylight type film.

Filter for white balance acquisition

By acquiring the manual white balance while wearing it, it is accurate under the light source.White balanceYou can get the state.

Anomalous reflection removal (DR) filter

Cloth dyed with aniline dye has a strong absorption band at a specific wavelength, and as a result, the color image taken may be expressed differently from the original color, which is called irregular reflection.An irregular reflection removal filter was developed to suppress this phenomenon.KenkoIt is a product name of.

Soft filter

Soft focus lensA filter that produces a slightly blurry effect, as if it was taken with. There is an image effect such as "fantastic".There are many types such as Dute, Softon, and Foggy.

  • Dute(Duto) --A filter that gives a weak soft effect by corroding colorless transparent glass concentrically.
  • Softon(Softon)-A filter that produces a soft effect by creating irregular irregularities on colorless transparent glass or plastic.
  • Foggy(Foggy)-A filter that creates a mist-like effect.If it's cold, you can substitute it by blowing lightly on the lens to make it cloudy.
  • Although not many, there are filters that produce the same optical effect (aberration) as soft focus lenses.

Cross filter

In the shining partRay systemA filter that generates.Where the water surface is shining with sunlight,light upWas doneNight viewWhen you take a picture of something like that, the feeling of glittering is emphasized.When it is simply called a cross filter, a filter with four rays is generally used.KenkoThen, the one with 6 raysSnow cross, 8 raysSunny cross, 4 rays, but the one whose angle can be adjustedBali clothIs called.

Lens protection filter (protector)

A colorless and transparent filter (lens protector / MC (multi-coated) protector) that only has the function of protecting the front lens from impact and dirt.Although some photographers avoid it if the optical performance and depiction ability of the lens body are reduced, the ones currently on the market have almost no effect on the ability of the lens body.However,Night viewIn shooting or backlit conditionsLens flareIt is still appropriate to remove it, as it may cause such problems.

High-end models have higher durability and stain resistance.

UVA cut filter or skylight filter may be used as a protective filter, but care must be taken because the skylight filter becomes reddish.

Close-up lens

Strictly speaking, it is not a filter, but it is used in the same way, and it is often treated as a type of filter, so I will explain it here.By attaching this lens, the shortest shooting distance will be shortened.Close-upShooting becomes possible.However, when used in combination with other filters, it is necessary to mount the close-up lens at the position closest to the lens body.Also different from macro lensesInfinityThere are restrictions on focusing, such as being out of focus.

The close-up lensConvex lensBecausefocusThe light incident on the close-up lens fromoptical axisBe parallel to.Therefore, it is possible to focus on a subject near the focal point by receiving the light passing through the close-up lens with a camera whose focus is set to infinity.By focusing the camera at a short distance, the focus position becomes closer than the focus of the close-up lens.

The number indicates the focal length (≈ the shooting distance when the focus ring of the main lens is set to infinity), but it should be noted that the display method differs depending on the manufacturer.In the case of Nikon, No. 0 is 1400 mm, No. 1 is 670 mm, No. 2 is 340 mm, No. 3T is 664.8 mm, and No. 4 T is 341 mm.In the case of Kenko, No. 1 is 1 / 1m = 1m, No. 2 is 1 / 2m = 50cm, No. 3 is 1 / 3m ≈ 33cm, and No. 10 is 1 / 10m = 10cm.

Infrared filter

Can't be felt with the naked eye,InfraredA filter that only transmits.Infrared filmUsed for.In addition, the image sensor of a digital camera has the property of sensing infrared rays, and by using this filter, it is possible to take an image of a strange image.Since the infrared sensing range differs depending on the model and the infrared wavelength is longer than that of visible light, it is necessary to manually adjust (focus) the shooting.

Classification by material

Glass filter

GlassA plate-shaped product made by mixing ingredients that have a filter effect.It is made into a disk shape and fitted in the frame, and the tip of the lensscrewMountain part (nutMost of the lenses are screwed into the slot (like this), but in the case of super-telephoto lenses, they are often fitted into the slot using a special holder.In addition to being released as genuine products by each camera and lens manufacturer, there are also filter specialist manufacturers such as Kenko and Marumi Kouki.in the pastToshibaWas also manufactured.

Gelatin filter

gelatin,acetateA thin sheet made by mixing materials such as dyes with ingredients that have a filter effect.The ancestorKodakSince the ratten filter was made of gelatin, it is made of acetate, which is used in a similar manner.FujiThe filter is also commonly called a "gelatin filter".Before the spread of digital cameras, professionals often used it for color correction because it allows fine color correction.Since it is a thin sheet, there is almost no risk of eclipse even if you put it in the holder.Cut it with scissors and stick it on the back lens of a super wide-angle lens,Electronic flashIt can also be used for special effects such as sticking with cellophane tape to the light emitting part of.

However, gelatin filters have low durability, and when wet with water, they retain their shape and become elastic and soft rubber, so it is necessary to avoid moisture.In addition, since fingerprints are easily attached and cannot be wiped off once it is applied, care must be taken when handling it, and mold grows, rots, and odors transfer, so it takes time and effort to store it in a dedicated refrigerator.In addition, since it easily fades and passes through, it is frequently replaced with a new one, which is costly.

On the other hand, the acetate filter does not change even if it gets wet, and even if it has fingerprints, it can be wiped off with a cleaner, and mold may grow like a lens, but it does not rot or smell, so it is relatively easy to store. Is.In addition, since it does not fade easily and does not easily fade, the frequency of replacement with a new one is low and the cost can be suppressed.

Plastic filter

CircularPlasticA board mixed, coated, or coated with ingredients that have a filter effect.Since plastic is easy to change its shape, it is often used as a filter for special effects such as a soft filter.Although it is not as easy as a gelatin filter, it is easily scratched, so care must be taken when handling it.

Classification by shape

Sheet filter

Gelatin filters and acetate filters fall into this category. There are 75 x 75 mm and 100 x 100 mm products.

Circular filter

The majority of glass or plastic filters have this shape.

Square filter

Filter, Lee filter (Lee Filters), Cokin ()[11]Products are known.

Classification by mounting standard

Screw type

Most filters are in this format.It is fitted in a round metal frame and attached with attachment screws.Many products are attached to the front end of the lens, but if the super-telephoto lens has a large aperture at the front end or if the ultra-wide-angle lens cannot attach the filter to the front end in the first place, it may be attached to the rear end.

Bayonet type

It is fitted in a round metal frame and attached with an attachment bayonet.Hasselblad,Rollei,Contarex,AlpaEtc. have their own standards.AlsoLens for Pentax 67In addition to being used in some of Nikon's ultra-wide-angle lenses, some products use a bayonet-type filter that is attached to the rear end.It is easy and quick to replace, but the filters are often expensive, the types are limited due to lack of versatility, and it is difficult to obtain after discontinuation of production.To avoid this, some Contarex and Pentax 67 lenses can also be screwed.

Series type

Use by sandwiching it between the ring and the hood or holder.There are roughly two types, a bare filter and a frame filter.The bare filter is only a round glass plate without a frame, but the old type has a gelatin filter sandwiched between two glass plates.The frame filter has a shape in which a metal frame without screw cutting is fitted, and the thickness of the frame and the glass plate are almost the same.Although it is an old type of filter, it is still relatively easy to obtain.

Plug-in type

The lens barrel is provided with a slot that can be opened from the side, and it is attached by inserting it.It is mainly used for super-telephoto lenses that have a large aperture at the front end.The filter attached to the slot is often the same as the screw type because it is shared with a general lens.

Holder type

Use the sheet filter and square filter in a special holder.

Precautions for purchase

Since the filter cannot be attached unless it meets the lens attachment standard, it is necessary to check the attachment standard of the lens to be attached before purchasing.However, for example, if you want to attach a filter with a larger diameter to a certain lens, you may be able to attach it by sandwiching an adapter called a "step-up ring" between the lens and the filter.

Related item


  1. ^ For example, the filter that cuts light below 560 nm is SC56.
  2. ^ You can take similar pictures by shooting in black and white with the Wratten # 47 filter.
  3. ^ L37 in JIS symbol.
  4. ^ L39 in JIS symbol.
  5. ^ Corresponds to Wratten No. 7.Currently, all of them are quite difficult to obtain.
  6. ^ It does not correspond to any of Wratten Nos. 6 to 9.
  7. ^ R60 in JIS symbol.
  8. ^ R64 in JIS symbol.
  9. ^ KenkoW in the symbol of.
  10. ^ KenkoThe symbol for is C.
  11. ^ Both are handled by Kenko in Japan.

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