When working with camera lenses and optics, we need to consider the impact of the f-number on various aspects of photography. The f-number, also known as the aperture, plays a crucial role in determining the depth of field, exposure, and focus of an image.

The f-number, or f-stop, is a measure used to describe the aperture size in a camera lens. A lower f-number indicates a larger aperture, allowing more light to enter the camera, while a higher f-number indicates a smaller aperture, allowing less light to enter. This relationship is because the f-number is calculated by dividing the lens' focal length by the diameter of the aperture. More on f-numbers and aperture can be found on Wikipedia.

Aperture also impacts the shape of the out-of-focus elements, known as bokeh, in images. Lenses with more blades tend to produce smoother bokeh, while fewer blades result in a more polygonal shape. Adjusting the aperture can also create a starburst effect when shooting lights at night, with a smaller aperture (higher f-number) producing more defined stars.

In the glass forming process, it is necessary for the molding system to purge of oxygen and filled with inert gas, such as nitrogen and argon, in order to avoid detrimental reactions caused by oxygen including a deterioration of molding die and contact-induced glass sticking.

Adjusting the aperture has a direct impact on the amount of light entering the camera. Wider apertures, represented by smaller f-stop numbers (e.g., F/1.8), allow more light to enter, while narrower apertures, represented by larger f-stop numbers (e.g., F/16), permit less light. Keep in mind that wider apertures also result in a shallow depth of field, meaning a smaller portion of the image is in focus.

Nonaspheric lenses advantages disadvantages

Photography is an art that blends technical precision with creativity, and understanding the different elements that affect a photo is essential. One such element is the aperture, an adjustable opening in the lens that controls the amount of light entering the camera. The size of this opening is denoted by the f-number or f-stop.

Finally, aberrations are imperfections caused by the lens, which can impact image quality. There are two main types of aberrations: chromatic and spherical. Large apertures are more prone to spherical aberrations, causing a softening of the image. Small apertures, on the other hand, can cause chromatic aberrations that create color fringing in the final photograph.

In conclusion, mastering the f-number is vital in photography, as it directly impacts exposure, depth of field, and the overall look of your images. Careful consideration of the f-number allows us to create stunning and well-balanced photographs.

For lenses made with spherical surfaces, rays which are parallel to the optic axis but at different distances from the optic axis fail to converge to the same point. If the center of the image stay in focus an bright, the edges of the field apprear blurry and dimmeter.

Higher zoom lens is used when you shoot something small or from far distance. As you zoom to higher magnifications, the image dims since the amount of light entering lens decreases the more you zoom in. The same applies in the case when fast shutter speed is needed, such as photographing high-pace sport. The faster the shutter speed, the shorter the time image sensor is exposed to light, and the darker the resulting photograph.

Aspheric lenses have non-spherical shapes, and have a more complex front surface, such as ellips, parabola, hyberbola, quadric, as well as toric which resembles a section of the surface of a rugby ball or a doughnut. In this page, we are going to cover how conventional spherical lenses work and the advantages of aspheric lenses. For an introduction to aspheric lens, click the button below. Dr. Nazetaro’s Lesson ”Basics of Optical Glass” Types of Simple Lenses and How They Work Convex lens Biconvex Curved outward on both sides Plano-convex Flat on one side and curved outward on the other side Convex Meniscus Meniscus means a crescent moon or an object shaped like it. Curved inward on one side and curved outward on the other side more strongly. Thicker in the middle than they are at the edges. Images formed by lenses With convex lens Concave lens Biconcave Curved inward on both sides Plano-concave Flat on one side and curved inward on the other side Concave Meniscus Concave meniscus is a lens curved inward on one side and curved outward on the other side less strongly. Thicker at the edges than they are in the middle. Images formed by lenses With concave lens Why Aspheric Lens is Needed? What is Lens? Lenses are used when magnifying tiny or distant objects to help us see more detail. Also, a camera lens is used to make images of objects either on photographic films or on other media. Traditional simple lenses are spherical lenses, one or both sides are concave/convex or one of the surface is flat, and their shapes are often made by grinding and polishing. Disadvantages of Spherical Lens Higher zoom lens is used when you shoot something small or from far distance. As you zoom to higher magnifications, the image dims since the amount of light entering lens decreases the more you zoom in. The same applies in the case when fast shutter speed is needed, such as photographing high-pace sport. The faster the shutter speed, the shorter the time image sensor is exposed to light, and the darker the resulting photograph. The larger diameter lens will allow more light to be gathered. However, a larger diameter lens tends to be thicker than a smaller diameter lens, making it more likely to create aberration. What is Aberration? For lenses made with spherical surfaces, rays which are parallel to the optic axis but at different distances from the optic axis fail to converge to the same point. If the center of the image stay in focus an bright, the edges of the field apprear blurry and dimmeter. How is Spherical Aberration Corrected? Spherical aberration is typically minimized by combination of multiple lenses into an optical assembly. Also, by using fewer aspheric lenses instead of a greater number of conventional spherical lenses can reduce or eliminate the aberration. Aspheric Lens Which can Reduce or Eliminate Spherical Aberration Aspheric lens has a non-spherical lens surface. The main advantage of aspheric lenses is its ability to correct for spherical aberration. Aspheric lenses allow optical designers to correct aberrations using fewer elements than conventional spherical optics because the former gives them more aberration correction than multiple surfaces of the latter. Given that, smaller amount of aspheric lenses can be substituted for many spherical lenses to achieve similar or better optical results, while reducing system size, simplifying the assembly process, and yielding imaging lenses that ultimately cost less and outperform assemblies made of traditional spherical components. However, aspheric lenses are not free from problems. Aspheric lenses tends to be more difficult to be manufactured by conventional fabrication prosess such as grinding and polishing, since aspheric lens elements are more complex than spherical ones. Consequently, aspheric lenses had not been widely applied. As an alternative approach, aspheric lenses can be manufactured by glass molding process: a preform or near-net-shape glass is introduced to heated molds within a molding machine, pressed by two mold halves, then the formed lens is cooled down and released from the molds. Glass molding is as an effective approach to produce precision optical elements with complex shapes at high production efficiency. Once the mold is finished, the incremental cost for each lens is lower than that of standard manufacturing techniques for aspheres, making this technique a great option for high volume production. Glass molding had an issue that arise from the very high-temperature for softening of a glass, which can deteriorate the molding easily and shorten the service life of molds. Requiring high temperature also means it takes time to heat and cool down the mold. Thus, the development of low softening temperature optical glasses for molding had been expected for a long time. Glass material for molding has additional requirements, such as transparency, excellence in scratch resistance, stability in optical properties in temperature changes, the properties include refractive index, no crystalization or volatile substances occurs while forming, not containing a material which can react with molds, and are free from pollutants, such as lead and arsenic compounds. Glass lens has advantages over the plastic lens on the aspects as shown above, as well as hardness, refractive index, light permeability, stability to environmetal changes in terms of temperature and humidity, although plascic lens can be mass-produced at a low cost. Furthermore, for the convenience of users, providing a wide variety of glass materials for molding is important to meet customers’ needs. Considering these requirements, SUMITA successfully developed a new glass material for molding, ‘K-PG325 Super Vidron’ with low softening temperature at 325 ℃ (617 ℉) in 2002. Since then, SUMITA has been developed a wide variety of glass materials for molding. Also, a preform has improved. Conventionally, a lens preform, shaped in ball, disc or near-net, generated out of raw glass by grinding and polishing processes. A gob preform, a firepolished preform produced directly from the melt without any additional surface processing, has developed and commercialized. For many years, SUMITA has been a reliable supplier for precision gob preforms made of glass materials for molding. Glass Modling Machine In order to cost effectively manufacture of the lens, heating and cooling cycle is optimized for the fastest possible cycle time. There is a series of additional requirements which must be considered to produce high precision molded aspherical lenses, including control of temperature and pressing load in a high accuracy, and the uniformity of temperature in glass, since non-uniformity of temperature in glass will cause distortion. In the glass forming process, it is necessary for the molding system to purge of oxygen and filled with inert gas, such as nitrogen and argon, in order to avoid detrimental reactions caused by oxygen including a deterioration of molding die and contact-induced glass sticking. Recently, SUMITA manufactures not only molded aspheric lenses but also molded diffraction gratings, microlens arrays and other surfaces microstructures. The surface profile of the molded lenses can be precisely controlled by changing the applied gas pressure. SUMITA’s ‘Vacuum Osvvesita’ is the optimum glass molding machine for research and development and a small lot production.

When comparing f-numbers, it's essential to keep in mind that each increase or decrease in f-stop represents a doubling or halving of the amount of light entering the camera. F-numbers are essentially a fraction, so a lower f-number like f/2.0 indicates wider aperture than f/4.0. This knowledge allows us to easily make adjustments to achieve our desired results3.

A small aperture is represented by a higher f-number, such as f/16 or f/22. This results in a smaller opening through which light can pass. Our images will have a larger depth of field, meaning that more of the scene will be in focus. However, the trade-off is that less light reaches the camera sensor, which can lead to increased noise in low-light conditions. One advantage of a small aperture is producing starburst and sunstar effects in your images.

As an alternative approach, aspheric lenses can be manufactured by glass molding process: a preform or near-net-shape glass is introduced to heated molds within a molding machine, pressed by two mold halves, then the formed lens is cooled down and released from the molds. Glass molding is as an effective approach to produce precision optical elements with complex shapes at high production efficiency. Once the mold is finished, the incremental cost for each lens is lower than that of standard manufacturing techniques for aspheres, making this technique a great option for high volume production.

Adjusting the f-number is crucial when dealing with exposure in photography. Proper exposure is a balance between aperture, shutter speed, and ISO settings. Changing the f-number affects both the depth of field and the amount of light that reaches the camera sensor. Therefore, understanding how to modify the f-number helps in controlling these aspects and capturing the desired image2.

Recently, SUMITA manufactures not only molded aspheric lenses but also molded diffraction gratings, microlens arrays and other surfaces microstructures. The surface profile of the molded lenses can be precisely controlled by changing the applied gas pressure. SUMITA’s ‘Vacuum Osvvesita’ is the optimum glass molding machine for research and development and a small lot production.

To summarize, adjusting the f-number in accordance with the desired outcome and photographic conditions allows us to create images with better quality and impact. From macro photography to capturing low-light scenes or wildlife, understanding the aperture's role in different scenarios is essential for every photographer.

Also, a preform has improved. Conventionally, a lens preform, shaped in ball, disc or near-net, generated out of raw glass by grinding and polishing processes. A gob preform, a firepolished preform produced directly from the melt without any additional surface processing, has developed and commercialized. For many years, SUMITA has been a reliable supplier for precision gob preforms made of glass materials for molding.

Aspheric Lensesprice

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On the other hand, a large aperture has a smaller f-number (e.g., f/1.4 or f/2.8). With a larger opening, more light can enter the camera. This allows for faster shutter speeds and improved low-light performance. Large apertures create a smaller depth of field, which helps create a more prominent subject-background separation, often referred to as bokeh. The maximum aperture of a lens indicates the widest setting available.

Disadvantagesofaspheric lenses

The bokeh effect refers to the aesthetic quality of the out-of-focus areas in an image. Aperture size influences this effect by controlling the depth of field. A larger aperture (lower f-number) creates a shallower depth of field, which means more areas of the image will be out of focus, resulting in a more pronounced bokeh effect. Conversely, a smaller aperture (higher f-number) creates a deeper depth of field, leading to fewer out-of-focus areas and a less pronounced bokeh. Photographylife explains the relationship between aperture and bokeh in this article.

Glass molding had an issue that arise from the very high-temperature for softening of a glass, which can deteriorate the molding easily and shorten the service life of molds. Requiring high temperature also means it takes time to heat and cool down the mold. Thus, the development of low softening temperature optical glasses for molding had been expected for a long time.

Aspheric lensesmeaning

When discussing camera lenses, aperture size plays a crucial role in determining the amount of light that reaches the camera sensor. The aperture diameter is measured using the f-number or f-stop. In this section, we will explore the implications of various aperture sizes on photography.

In order to cost effectively manufacture of the lens, heating and cooling cycle is optimized for the fastest possible cycle time. There is a series of additional requirements which must be considered to produce high precision molded aspherical lenses, including control of temperature and pressing load in a high accuracy, and the uniformity of temperature in glass, since non-uniformity of temperature in glass will cause distortion.

For an introduction to aspheric lens, click the button below. Dr. Nazetaro’s Lesson ”Basics of Optical Glass” Types of Simple Lenses and How They Work Convex lens Biconvex Curved outward on both sides Plano-convex Flat on one side and curved outward on the other side Convex Meniscus Meniscus means a crescent moon or an object shaped like it. Curved inward on one side and curved outward on the other side more strongly. Thicker in the middle than they are at the edges. Images formed by lenses With convex lens Concave lens Biconcave Curved inward on both sides Plano-concave Flat on one side and curved inward on the other side Concave Meniscus Concave meniscus is a lens curved inward on one side and curved outward on the other side less strongly. Thicker at the edges than they are in the middle. Images formed by lenses With concave lens Why Aspheric Lens is Needed? What is Lens? Lenses are used when magnifying tiny or distant objects to help us see more detail. Also, a camera lens is used to make images of objects either on photographic films or on other media. Traditional simple lenses are spherical lenses, one or both sides are concave/convex or one of the surface is flat, and their shapes are often made by grinding and polishing. Disadvantages of Spherical Lens Higher zoom lens is used when you shoot something small or from far distance. As you zoom to higher magnifications, the image dims since the amount of light entering lens decreases the more you zoom in. The same applies in the case when fast shutter speed is needed, such as photographing high-pace sport. The faster the shutter speed, the shorter the time image sensor is exposed to light, and the darker the resulting photograph. The larger diameter lens will allow more light to be gathered. However, a larger diameter lens tends to be thicker than a smaller diameter lens, making it more likely to create aberration. What is Aberration? For lenses made with spherical surfaces, rays which are parallel to the optic axis but at different distances from the optic axis fail to converge to the same point. If the center of the image stay in focus an bright, the edges of the field apprear blurry and dimmeter. How is Spherical Aberration Corrected? Spherical aberration is typically minimized by combination of multiple lenses into an optical assembly. Also, by using fewer aspheric lenses instead of a greater number of conventional spherical lenses can reduce or eliminate the aberration. Aspheric Lens Which can Reduce or Eliminate Spherical Aberration Aspheric lens has a non-spherical lens surface. The main advantage of aspheric lenses is its ability to correct for spherical aberration. Aspheric lenses allow optical designers to correct aberrations using fewer elements than conventional spherical optics because the former gives them more aberration correction than multiple surfaces of the latter. Given that, smaller amount of aspheric lenses can be substituted for many spherical lenses to achieve similar or better optical results, while reducing system size, simplifying the assembly process, and yielding imaging lenses that ultimately cost less and outperform assemblies made of traditional spherical components. However, aspheric lenses are not free from problems. Aspheric lenses tends to be more difficult to be manufactured by conventional fabrication prosess such as grinding and polishing, since aspheric lens elements are more complex than spherical ones. Consequently, aspheric lenses had not been widely applied. As an alternative approach, aspheric lenses can be manufactured by glass molding process: a preform or near-net-shape glass is introduced to heated molds within a molding machine, pressed by two mold halves, then the formed lens is cooled down and released from the molds. Glass molding is as an effective approach to produce precision optical elements with complex shapes at high production efficiency. Once the mold is finished, the incremental cost for each lens is lower than that of standard manufacturing techniques for aspheres, making this technique a great option for high volume production. Glass molding had an issue that arise from the very high-temperature for softening of a glass, which can deteriorate the molding easily and shorten the service life of molds. Requiring high temperature also means it takes time to heat and cool down the mold. Thus, the development of low softening temperature optical glasses for molding had been expected for a long time. Glass material for molding has additional requirements, such as transparency, excellence in scratch resistance, stability in optical properties in temperature changes, the properties include refractive index, no crystalization or volatile substances occurs while forming, not containing a material which can react with molds, and are free from pollutants, such as lead and arsenic compounds. Glass lens has advantages over the plastic lens on the aspects as shown above, as well as hardness, refractive index, light permeability, stability to environmetal changes in terms of temperature and humidity, although plascic lens can be mass-produced at a low cost. Furthermore, for the convenience of users, providing a wide variety of glass materials for molding is important to meet customers’ needs. Considering these requirements, SUMITA successfully developed a new glass material for molding, ‘K-PG325 Super Vidron’ with low softening temperature at 325 ℃ (617 ℉) in 2002. Since then, SUMITA has been developed a wide variety of glass materials for molding. Also, a preform has improved. Conventionally, a lens preform, shaped in ball, disc or near-net, generated out of raw glass by grinding and polishing processes. A gob preform, a firepolished preform produced directly from the melt without any additional surface processing, has developed and commercialized. For many years, SUMITA has been a reliable supplier for precision gob preforms made of glass materials for molding. Glass Modling Machine In order to cost effectively manufacture of the lens, heating and cooling cycle is optimized for the fastest possible cycle time. There is a series of additional requirements which must be considered to produce high precision molded aspherical lenses, including control of temperature and pressing load in a high accuracy, and the uniformity of temperature in glass, since non-uniformity of temperature in glass will cause distortion. In the glass forming process, it is necessary for the molding system to purge of oxygen and filled with inert gas, such as nitrogen and argon, in order to avoid detrimental reactions caused by oxygen including a deterioration of molding die and contact-induced glass sticking. Recently, SUMITA manufactures not only molded aspheric lenses but also molded diffraction gratings, microlens arrays and other surfaces microstructures. The surface profile of the molded lenses can be precisely controlled by changing the applied gas pressure. SUMITA’s ‘Vacuum Osvvesita’ is the optimum glass molding machine for research and development and a small lot production.

A vital aspect of photography, the f-number has a direct impact on image quality as it influences the depth of field and sharpness. When working with the f-number, it's crucial to grasp how larger and smaller apertures will affect the image. By manipulating this aspect, photographers can achieve their desired results and elevate their photo-taking skills.

A lens' focal length is another vital aspect. The relationship between aperture and focal length is expressed by the f-number. F-number is calculated as the focal length divided by the diameter of the aperture in the lens. For example, with a 50mm focal length and an aperture diameter of 25mm, the f-number would be F/2.

Aspheric lens has a non-spherical lens surface. The main advantage of aspheric lenses is its ability to correct for spherical aberration. Aspheric lenses allow optical designers to correct aberrations using fewer elements than conventional spherical optics because the former gives them more aberration correction than multiple surfaces of the latter. Given that, smaller amount of aspheric lenses can be substituted for many spherical lenses to achieve similar or better optical results, while reducing system size, simplifying the assembly process, and yielding imaging lenses that ultimately cost less and outperform assemblies made of traditional spherical components.

However, aspheric lenses are not free from problems. Aspheric lenses tends to be more difficult to be manufactured by conventional fabrication prosess such as grinding and polishing, since aspheric lens elements are more complex than spherical ones. Consequently, aspheric lenses had not been widely applied.

Aspheric lenses advantages disadvantageswikipedia

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The working f-number determines the image's resolution quality, considering the lens and camera sensor combination. A balance between the f-number and camera sensor's sensitivity is essential to achieve optimal image quality.

In conclusion, understanding the effects of aperture on image quality is crucial for every photographer. By considering factors like depth of field, diffraction, brightness, and aberrations, we can make informed decisions to capture the best possible images.

Asphericcontactlenses

The depth of field refers to the area within a photograph where the objects appear to be in focus. A large aperture (like f/1.8) results in a shallow depth of field, creating a beautiful bokeh effect in the background. On the other hand, a small aperture (such as f/16) increases the depth of field, bringing more of the scene into focus.

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In macro photography, a small aperture (higher f-number) is often preferred to have a deeper depth of field, ensuring the subject is in focus. However, a larger aperture (smaller f-number) allows more light to enter and can be beneficial in low-light conditions. For wildlife photography, a fast lens with a lower f-number is advantageous for capturing a fast-moving subject.

When it comes to photography, aperture plays a significant role in affecting the image quality. In this section, we will discuss the different aspects impacted by the f-number, such as depth of field, diffraction, and more.

Different lenses come with varying maximum aperture sizes due to their design and construction. Factors such as focal length, lens elements, and manufacturing processes can impact the maximum aperture a lens can achieve. Generally, lenses with larger maximum apertures (lower f-numbers) require more complex and costly designs.

When it comes to photography, one of the key factors that affects the final image is the aperture. The aperture is the opening in a lens through which light passes to enter the camera. This opening can be adjusted and is measured by the f-stop.

As the f-number controls the aperture size and indirectly the amount of light entering the camera, changing the f-number also affects the shutter speed. To maintain the desired exposure, when the aperture is decreased (higher f-number), a slower shutter speed may be required to allow more light in, whereas when the aperture is increased (lower f-number), a faster shutter speed can be used to prevent overexposure.

Aspheric lensesvs spherical

Lenses are used when magnifying tiny or distant objects to help us see more detail. Also, a camera lens is used to make images of objects either on photographic films or on other media. Traditional simple lenses are spherical lenses, one or both sides are concave/convex or one of the surface is flat, and their shapes are often made by grinding and polishing.

When working with the f-number, it's important to understand its role in photography. The f-number, also known as f-stops, represents the ratio of a lens's focal length to the diameter of the aperture opening. As a dimensionless value, it plays a vital role in determining the size of the aperture and the amount of light entering the camera. A smaller f-number means a larger aperture and more light entering the camera, while a larger f-number means a smaller aperture and less light entering the camera1.

Spherical aberration is typically minimized by combination of multiple lenses into an optical assembly. Also, by using fewer aspheric lenses instead of a greater number of conventional spherical lenses can reduce or eliminate the aberration.

Considering these requirements, SUMITA successfully developed a new glass material for molding, ‘K-PG325 Super Vidron’ with low softening temperature at 325 ℃ (617 ℉) in 2002. Since then, SUMITA has been developed a wide variety of glass materials for molding.

A narrow aperture can be used interchangeably with "small aperture," while a wide aperture refers to a "large aperture." The terminology emphasizes the different characteristics associated with the size of the aperture opening.

The larger diameter lens will allow more light to be gathered. However, a larger diameter lens tends to be thicker than a smaller diameter lens, making it more likely to create aberration.

The brightness of an image is also directly influenced by the aperture size. A large aperture allows more light to enter the camera, producing a brighter image. Conversely, a smaller aperture reduces the amount of light, resulting in a darker image.

In summary, the size of the aperture affects the amount of light reaching the camera sensor, depth of field, and creative effects we can achieve in our photographs. Selecting the appropriate aperture size based on the desired outcome is an essential aspect of photography. The range of apertures offered by a lens - from wide to narrow - provides photographers with various creative and technical options for capturing their vision.

Diffraction is a phenomenon that adversely affects the sharpness of an image. As the aperture gets smaller (higher f-number), the lightwaves passing through the diaphragm start to diffract, leading to a decrease in image resolution. To avoid this issue, it's essential to find the optimal aperture for your lens.

Lastly, it is essential to remember that lens quality plays a significant role in the outcome of a photograph. Modern camera lenses have multiple elements and sophisticated designs that affect overall image sharpness and clarity. It is crucial to invest in lenses that suit your specific needs and preferences as you progress in your photography journey.

The aperture size directly affects the amount of light passing through the lens and onto the camera sensor. A larger aperture (represented by a lower f-number) allows more light to enter, resulting in a brighter image and a potentially shorter shutter speed, while a smaller aperture (higher f-number) allows less light to pass through, resulting in a darker image and potentially necessitating a longer shutter speed. This guide provides an easy-to-understand explanation of aperture's impact on exposure.

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Aperture settings play a significant role in determining the depth of field in a photograph. A larger aperture (lower f-number) will result in a shallower depth of field, with only a small area of the image in focus. Conversely, a smaller aperture (higher f-number) will create a deeper depth of field, with a larger area in focus. This concept is explained in more detail in this article.

Glass material for molding has additional requirements, such as transparency, excellence in scratch resistance, stability in optical properties in temperature changes, the properties include refractive index, no crystalization or volatile substances occurs while forming, not containing a material which can react with molds, and are free from pollutants, such as lead and arsenic compounds. Glass lens has advantages over the plastic lens on the aspects as shown above, as well as hardness, refractive index, light permeability, stability to environmetal changes in terms of temperature and humidity, although plascic lens can be mass-produced at a low cost. Furthermore, for the convenience of users, providing a wide variety of glass materials for molding is important to meet customers’ needs.

(https://medium.com/photography-from-near-and-afar/f-numbers-the-essential-guide-to-aperture-and-its-impact-on-photography-c7312c1a010c) ↩