Learning MAYA is an animation major, but what knowledge is needed besides software, such as lens, please introduce it in detail. Thank you.

Difference between lens performance and shape

According to the performance and appearance of lenses, there are currently P-type, E-type, L-type and auto-zoom lenses. The information from China Instrument Supermarket is described as follows:

1.p lens

The automatic positioning lens of micro-vision industrial lens (1) has adjusted its pupil focal length, so it is necessary to check whether the definition from the maximum magnification to the minimum magnification is consistent and clear.

(2) Check the coaxiality, that is, the images from the maximum magnification to the minimum magnification are taken at the same position, and cannot be offset or offset too much, which is regarded as defective, and the lens must be replaced again.

(3) The optical magnification is 0.7—4.5X, that is, 9 magnifications ranging from 0.7 to 4.5 times.

(4) Judging the clarity according to the imaging reflection of the correction block and the actual object.

2.e lens

(1) This lens is an ordinary industrial lens, and the pupil focal length needs to be adjusted manually. After the machine is installed, when the maximum magnification and the minimum magnification are manually adjusted, the image is equally clear. Those whose sharpness cannot be adjusted are regarded as defective products, and those with unstable factors such as jitter after adjustment are also regarded as defective products.

(2) Check the coaxiality, that is, the images from the maximum magnification to the minimum magnification are taken at the same position, and cannot be offset or offset too much, which is regarded as defective, and the lens must be replaced again.

The optical magnification of enlarger lens (3) is 0.7-4.5 times. ..

(4) Explain the definition according to the imaging reflection of the calibration block and the actual object.

3.l lens

(1) This lens is an ordinary industrial lens, and the pupil focal length needs to be adjusted manually. After the machine is installed, manually adjust the maximum magnification and minimum magnification, and the image is also clear. Those whose sharpness cannot be adjusted are regarded as defective products, and those with unstable factors such as jitter after adjustment are also regarded as defective products.

(2) Check the coaxiality, that is, the images from the maximum magnification to the minimum magnification are taken at the same position, and cannot be offset or offset too much, which is regarded as defective, and the lens must be replaced again.

(3) the optical magnification is 0.7-4.5 times. ..

(4) Explain the definition according to the imaging reflection of the calibration block and the actual object.

4. Automatic zoom lens

(1) Automatic positioning, the pupil focus of the lens itself has been adjusted, and it is necessary to check whether the definition from the maximum magnification to the minimum magnification is consistent and clear.

(2) Check the coaxiality, that is, the images from the maximum magnification to the minimum magnification are taken at the same position, and cannot be offset or offset too much, which is regarded as defective, and the lens must be replaced again.

(3) the optical magnification is 0.7-4.5 times. ..

(4) Explain the definition according to the imaging reflection of the calibration block and the actual object.

[Edit this paragraph] Dictionary explanation

1. An optical device consisting of a lens on a camera, video camera or projector. Used for imaging on a negative or screen. Lu Xun's "Essay on the Pavilion": "Children's expressions always change under the lens of a camera."

2. photos taken by the camera. Xue Muqiao's "Several Problems on the Road to Modernization in China": "State-owned photography shops such as Tiananmen Square and Beihai Park only take one shot, and cooperative photography teams are free to choose a shot."

3. A series of photos taken by movie cameras and TV cameras. When they start to turn to a stop. The first part is Hong Shen's preliminary understanding of drama directors: "For example, the use of' close-up',' fantasy',' fade-in',' fade-out',' blend' and' crossing' in naturalistic film and television dramas has its own reasons and effects." Ke Yan's "Oriental Wonder Book Jane Pearl III": "After the film is finished, slow down this shot by a thousand times, so that the artist can observe its expression carefully and repeatedly."

4. A scene in life. Ding Ling, director of Liangmo, said: "At night, they don't stop working, there are searchlights, and people are hanging on the shelves to work. The shadow on the shelf sticks to the cliff like a pattern. What a magnificent blow. " Cao Jinghua's "Flying Flowers: How to Have Leisure": "Close your eyes and meditate, and a small lens immediately comes to my mind."

[Edit this paragraph] Professional explanation

The lens has two fingers in film and television. One is the optical element used by film cameras and projectors to produce images, which consists of multiple lenses. Different lenses have different modeling characteristics, and their application in photographic modeling constitutes an optical expression means; The second finger refers to the picture taken continuously from power on to power off, or the fragment between two editing points, also called ytterbium head. One finger and two fingers are two completely different concepts. In order to distinguish, one refers to the optical lens and the other refers to the lens picture.

The main function of the lens is to collect the reflected light of the illuminated object and focus it on the CCD. The image projected on the CCD is inverted, and the camera circuit has the function of inversion. Its imaging principle is the same as that of human eyes.

1. Classification of lens

The classification of lenses can be classified according to focal length, focal length digital size, aperture division and lens telescopic adjustment.

(1). According to the focal length, there are fixed focal length, telescopic, automatic aperture or manual aperture.

(2) According to the digital size of the focal length, there are standard lenses, wide-angle lenses and telescope heads.

(3) According to the classification of aperture, there are fixed aperture, manual aperture and automatic aperture.

(4) According to the lens telescopic adjustment mode, there are electric telescopic lenses, manual telescopic lenses and other types.

2. Factors that determine the quality of lenses

(1). Number of lenses: Multi-type lens combination can reduce color shift and improve focus, but it will reduce light transmittance.

(2) Lens transmittance: A good lens transmittance is good and expensive, while a poor lens will block light from passing through.

(3) Coating and grinding: The coating and grinding process of lenses affects the quality of lenses.

(4) Mechanical device: The precision of the internal mechanical structure of the lens affects the precision coating of the lens and the reliability of the movement. Poor mechanical structure will lead to adjustment errors and inconsistencies.

[Edit this paragraph] Brand lens

Starting from the lens of digital camera (brief introduction of brand lens)

● German trump card-chasing the camera

If the value of a camera is that it can take good photos, the most important factor to ensure the quality of photos is to have a lens with outstanding performance. Various manufacturers are constantly innovating lenses when launching new products. Manufacturers with independent research and development capabilities are trying to release their own lenses, while manufacturers without research and development capabilities are also trying to find partners to develop lenses suitable for their cameras. Casio, Samsung and other manufacturers initially relied on Schneider and Pentax lenses, and later developed their own ceramic lenses and SHD lenses. On the other hand, Sony and Panasonic are closely wooing the long-established German lens manufacturers and using their mature technology to ensure the imaging effect of their cameras. Therefore, to choose a good brand, we must first recognize what lens we are using and be aware of it.

Carl Zeiss lens

Carl Zeiss lens is a German brand and one of the few non-Japanese manufacturers. Carl zeiss is a manufacturer of optical instruments with a long history. Its lens has always been synonymous with "nobility" in the field of traditional cameras, and many color lovers are proud of having Carl Zeiss lenses. Sony has used Carl Zeiss lenses as a selling point on some of its digital cameras. It should be noted that Sony's high-end digital cameras generally use Carl Zeiss lenses, while low-end products use ordinary Sony lenses.

Recommended model:

As the thinnest optical zoom digital camera in the world, T7 has been sought after by fashionistas since its launch, and its sales have been good. It uses a 1/2.4-inch 5-megapixel CCD and a carl zeiss lens with 3x optical zoom. Its imaging level is in the middle and upper reaches of similar models, but its body is very exquisite, with a high-definition 2.5-inch display. This is an excellent card digital camera.

● The real best-Leica lens

Leica is also a German optical instrument manufacturer with a long history. Its products are not inferior to the above brands in the world, and they can also be called "the best". In the field of digital cameras, Leica's most outstanding achievement is to design and produce lenses for Panasonic LUMIX series digital cameras and achieve success. At the same time, Leica's only digital camera Digitlux 1 also uses Leica lens.

Recommended model:

Panasonic Lumix DMC-FX8 uses a CCD with 1/2.5 inches and 5 effective pixels. The lens adopts a triple optical zoom lens with a focal length of 35- 105mm and an aperture range of F 2.8-5.0. The lens of Panasonic FX8 is still provided by Leica. On the LCD screen, Lumix DMC-FX8 has not been upgraded, and still uses a 2.5-inch LCD screen with 1 1.4 million pixels. Lumix DMC-FX8, like FX7, adopts Panasonic's unique image anti-shake technology, which can make your picture clearer and sharper.

● Long history-Schneider lens

Schneider (Germany) has a long history of producing large-format lenses, and is famous for its wide variety and high quality. At present, it has several series of dozens of lenses, including ultra-wide-angle to 800mm telescope lenses with a focal length of 38 mm Schneider Kreuznach Schneider Crut Nach is a world-famous professional manufacturer of optical lenses and hydraulic servo components, and enjoys a high reputation in the industry. Our products include: various optical lenses (cameras, CCD, camcorders), hydraulic servo components, etc. , widely used in all walks of life.

Recommended model:

In fact, Z7590 and DX7590 are basically the same, which can be said to be a renamed version of DX7590 introduced by Kodak according to its new naming rules. German Schneider lens with optical zoom of 10x, 2.2-inch LCD, 5 megapixels 1/2.5-inch CCD and manual exposure mode are also adopted. However, as a telephoto camera, it is not stable, which is very incomprehensible! I'm afraid the photos taken when there is no fixed fuselage will be very empty, which is really terrible compared with telephoto machines from other manufacturers!

● Canon lens, a major optical manufacturer.

Canon is a traditional optical manufacturer, and its EF series lenses in the field of traditional cameras, especially the red circle lens representing aristocratic descent, have always been the dream of many photographers. Therefore, with years of accumulated experience in the field of traditional lens manufacturing, Canon's digital camera lenses are also of first-class quality. Canon lens has sharp imaging and true color reproduction, which effectively ensures the final imaging quality.

Recommended model:

PowerShot A520 uses a 4 effective pixel CCD and is equipped with a newly designed retractable 4x optical zoom lens. Its focal length is equivalent to 35- 140mm of 135 camera, its maximum aperture is F2.6 (wide angle) -5.5 (telephoto), and its optical structure is seven five lenses, including two aspherical lenses. This kind of high-quality 4x zoom lens can be conveniently used for shooting life scenes, general portrait photos and scenery shooting in tourism. Although it has a larger zoom ratio, the body size and weight of PowerShot A520 are reduced by 13% compared with PowerShot A85.

● The strongest Japanese-nikkor lens

Nikon is a world-famous lens manufacturer with the same reputation as Canon, and its Nikkor series lenses are loved by photographers for their excellent imaging quality. Nikon's digital cameras all use Nicol series lenses, especially some high-end models, and also use expensive ED (ultra-low dispersion) lenses to obtain perfect images. Although these high-end models are expensive, many photographers don't choose them because their lenses are excellent, not Nikon's digital cameras.

Recommended model:

CoolPix5900 continues the slim appearance of CoolPix5200, with no battery weight 185g. Although it is small and feels quite good, the metal body is also in line with popular fashion elements. From this point of view, Nikon's previous CoolPix5200 was quite successful. In the selection of photosensitive elements, CoolPix5900 still uses11.8 inch CCD, with effective pixels of 565,438+million, and can take photos with the maximum size of 2,592×1944 pixels, which is widely used in 5 million models today.

● Old shop-Pentax lens

Pentax lens: Pentax's fame doesn't seem as loud as the brand mentioned above. Actually, it is not. Pentax not only has high attainments in the field of 135mm professional SLR cameras, but also has many specialties in China movies. There are not many Pentax digital cameras, but each camera uses excellent Pentax lenses. In addition, Pentax also designs and supplies lenses for other manufacturers, such as Casio and BenQ.

Recommended camera:

Besides Pentax's own homemade lenses, more loyal users are BenQ and Casio. Using Pentax lens really makes the camera much thinner!

R6 1 is faster, 1 s boot time, and 0.0 1 s shutter lag; Better operation mode, such as: three-stage self-timer function, users can take three photos in a row at regular intervals, and then choose the one they are satisfied with; R6 1 has a larger face and is equipped with a 2.0-inch TFT LCD screen with a display accuracy of 85,000 pixels.

● Optical Tradition-Fuji Dragon Lens

In addition to producing and selling films all over the world, Fuji is also a traditional camera manufacturer, and its lens brand is Fuji Dragon. After entering the digital age, Fuji is making every effort to promote the popularization of digital cameras. In order to ensure the excellent imaging quality, Fuji has made great efforts in the lens, and used super EBC coating on the lens, which has played a great role in improving the performance of the lens, which is enough to show Fuji's good intentions.

Recommended camera:

What are the advantages of digital SLR cameras compared with small consumer DC? I am afraid that apart from the imaging quality of the lens and the reaction speed of focusing, the most important factor is that the image noise is well controlled under high ISO. However, Fuji F 10, which was very popular for a while, is famous for its acceptable image quality under ISO 1600. Fuji FinePix F 10 adopts the SuperCCD and real image technology developed by Fuji, which can not only effectively control the noise under high ISO, but also make F 10 have a high-speed shutter response time of about 0.065438 seconds and a high efficiency of taking 500 photos at one charge.

However, F 10 still has a fatal defect that the XD card it uses is very expensive. For example, a 256MB XD card needs 360 yuan, and a 5 12MB high-speed CF/SD card can be bought at the same price, which is very stressful for novices! In terms of actual performance, high-speed SD/CF is better than XD, so everyone should think more before buying.

● Carefully selected-Minolta GT lens

Minolta is also a famous manufacturer of optical equipment. One of the highlights of its digital camera is the GT lens-the letter "GT" indicates that it is an advanced lens specially used for digital cameras, which means that this lens is an extraordinary high-quality lens made by concentrating Minolta's unique key image processing technology (GT=G Lens Technology), which keeps chromatic aberration and distorted astigmatism to a minimum. Most of Minolta's DiMAGE series digital cameras use GT lenses.

Recommended camera:

DiMAGE X60 is equipped with 1/2.5-inch CCD and the latest CxProcess III imaging technology, which can make the imaging color more realistic and natural. The machine adopts a 3-fold optical zoom lens (equivalent focal length 38- 1 14mm) with a maximum aperture of F3.3-4.0. In addition, the 2.5-inch LCD screen of 1 1.5 million pixels makes it look better than X50, but the optical viewfinder has been replaced by the expansion of its LCD. The X60 has a macro focusing distance of 5cm and built-in memory 15MB, which can be extended by SD card.

Security monitoring field, lens classification, selection, lens calculation.

In TV monitoring system, it is very important to choose the correct camera lens according to the monitored environment, because it directly affects whether the effect of the monitored surface picture seen on the monitor at the end of the system can meet the design requirements of the system (in terms of picture range or image details), so choosing the camera lens correctly can optimize the design of the system and obtain good monitoring effect.

1. Classification:

Camera lens can be divided into manual aperture lens and automatic aperture lens according to aperture, and fixed focus lens and zoom lens according to focal length.

2. Choose the correct camera lens.

A. Selection of manual and automatic aperture lens

The choice of manual and automatic aperture lens depends on whether the illumination of the use environment is constant.

# In the case of constant ambient illumination, such as in elevator cars, closed corridors and rooms without direct sunlight, manual aperture lens can be selected, so that when the system is initially installed and debugged, the aperture size of the lens can be adjusted at one time according to the actual ambient illumination to obtain a satisfactory brightness picture.

# If the ambient lighting is constantly changing, such as foyer, window and lobby, etc. In places where the illumination changes greatly with the sunshine time, an automatic aperture lens is needed (a camera with an automatic aperture lens socket must be equipped), so that the brightness of the picture can be automatically adjusted and a good monitoring picture with constant brightness can be obtained.

The control signal of automatic aperture lens can be divided into DC and video control, namely DC voltage control and video signal control. In the selection of auto-stop lens type, the connection mode of camera auto-stop lens socket and the selection of auto-stop lens driving mode switch, the three should be coordinated well. 2. Choice of fixed focus and zoom lens

B. Selection of fixed focus and zoom lens

The choice of fixed focus and zoom lens depends on the size of the monitored scene range and the required clarity of the monitored scene picture.

When the lens specifications (generally divided into1/3 ",1/2" and 2/3 ",etc. ) are fixed, and the relationship between lens focal length and lens field of view angle is that the longer the lens focal length, the smaller the lens field of view angle (as shown in figure 1). When the focal length of the lens is fixed, the relationship between the lens specification and the lens field of view is that the larger the lens specification, the larger the lens field of view. Therefore, it can be seen from the above relationship: under the condition that the lens object distance is constant, with the increase of the lens focal length, the picture range of the monitoring scene seen on the monitor at the end of the system is smaller, but the picture details are clearer and clearer; With the increase of lens specifications, the picture range of the monitoring scene seen on the monitor at the end of the system increases, but its picture details become more and more blurred. On the premise of certain lens specifications and lens focal length, the field of view angle of CS interface lens will be larger than that of C interface lens.

The field of view of the lens can be divided into horizontal field of view and vertical field of view of the image, and the horizontal field of view of the image is greater than the vertical field of view of the image. Usually, the angle of view we say generally refers to the horizontal angle of view of a lens.

In a narrow monitoring environment, such as an elevator car, a short-focus wide-angle or ultra-wide-angle fixed-focus lens should be used in a narrow room. For example, if the lens specification is 1/2 "and the focal length of the lens is 3.6mm or 2.6mm, then the angle of view of these lenses is not less than 99 or127, which is about 2.5m for a camera in a narrow space. Manual zoom lenses such as T2Z28 14CS-2 lens of Nissan computer can also be selected according to the actual situation on site. This lens is a manual aperture lens with1/3 "cs interface, and the focal length can be adjusted twice (manual focusing). The focus range is 2.8 ~ 6.0 mm, and the viewing angle changes from 96 to 47.2. This kind of lens is very suitable for use in narrow monitoring environment, and can flexibly realize the monitoring effect of "point" or "surface" of monitoring scene according to actual needs.

For a general zoom lens, the minimum focal length is usually about 6.0mm, so the maximum field of view of the zoom lens is about 45. If this lens is used in such a narrow monitoring environment, its monitoring dead angle will inevitably increase. Although this kind of monitoring dead angle can be reduced by controlling the front-end pan/tilt, it will definitely increase the engineering cost of the system (the system needs to add front-end decoder, pan/tilt and pan/tilt).

In an open monitoring environment, firstly, according to the openness of the monitoring environment, the clarity of the monitoring scene picture required by the user on the monitor at the system end, and the linear distance between the center point of the monitoring scene and the camera lens, the telephoto lens should be considered as much as possible on the premise that the linear distance is certain and covers the whole monitoring scene picture, so as to obtain the monitoring scene picture with clearer details on the monitor at the system end. In this environment, zoom (magnifying) lens (electric three-variable lens) can also be considered, which can be determined according to the design requirements of the system and the cost performance of the system. Two points should be considered when selecting: (1) When adjusting to the shortest focal length (panorama), the requirements of covering the main monitoring scenes should be met; (2) When adjusting to the longest focal length (see), it should be able to meet the requirements of observing and monitoring the details of the scene. Usually in indoor warehouses, workshops, factories and other environments, 6 times or 10 times lens can meet the requirements, while in outdoor environments such as reservoir areas, docks, squares and stations. , 10 times, 16 times or 20 times lens can be selected according to actual requirements (generally speaking, the larger the lens multiple, the higher the price, which can be used for. n

C. theoretical calculation of correct selection of lens focal length

The field of view angle of the lens capturing the scene is an extremely important parameter. The field of view of the lens changes with the focal length of the lens and the size of the camera (the relationship is as mentioned above). The focal length of the lens covering the scene can be calculated by the following formula:

( 1) f=u？ D/U

(2) f=h？ D/H

F: focal length of lens, U: actual height of scene, H: actual width of scene, D: measured distance from lens to scene, U: image height, H: image width.

(3) For example, when 1/2 "lens is selected, the image size is u=4.8mm, H = 6.4mm. The distance from the lens to the scene is D = 3,500mm, and the actual height of the scene is U = 2,500mm (the actual width of the scene can be calculated by the following formula: H= 1.333). U, this relationship is determined by the camera viewfinder CCD).

Substituting the above parameters into the formula (1), you can get f=4.8? 3500/2500=6.72mm, so you can choose a 6mm fixed-focus lens.

Economic coagulant economic circle

Correct understanding of low-light camera

At present, the definition of low-light cameras advertised in the market, whether manufacturers or importers, has different opinions. Color cameras range from 0.0004 lux to 1LUX, and black-and-white cameras range from 0.0003 to 0. 1LUX (if matched with infrared rays, they can all reach 0 lux), which means that there is no unified standard for the technical specifications of CCTV industry in the domestic market. The insiders emphasize that how low the illumination can be depends not only on the aperture size (F value) of the lens, but also on the conditions under which the marked LUX value can appear, otherwise it will only be a digital game! In terms of aperture size (F value), the larger the aperture, the smaller the F value and the lower the required illumination. In addition, has the electronic sensitivity improved? What is the cumulative number of frames in a single picture? Is the infrared on or off? ..... and so on, so as not to be confused by the illumination value marked in the manual. The evolution of low-light cameras in China market can be simply divided into the following three steps: color/monochrome); During the day; Low speed shutter (SLOW/SHUTTER) and ultra-sensitive camera (EXVIEW/HAD).