DA 2 1mm F3.2 AL Limited who can explain the meaning of this lens parameter?

This is the middle end commonly used in Pentax lenses.

DA digital computer, the imaging area is APSC frame, which is less than the full width of 135 film.

2 1mm is the focal length. If the focal length is small, the viewing angle will be large and the shooting will be wider. On 135 film, 2 1mm is generally classified as wide angle and 50mm is the standard focus. But on a digital computer, 2 1 is multiplied by a coefficient of about 1.5, which is about 30mm film. This is a comparison. F3.2 is the maximum aperture. The smaller the value, the larger the aperture and the greater the luminous flux. F 1.7 is about 3.5 times that of F3.2 In dark light, you can use a faster shutter, and the depth of field in large aperture is shallower and easy to blur. Therefore, a large aperture is generally good and the cost is high.

Others look down upon it, hehe.

"fight"

Indicates that this lens belongs to a digital SLR camera and is marked with a green circle.

" F "

It's Pentax's AF lens bayonet.

"law"

It is also Pentax's AF lens bayonet, with two more contacts.

" FA* "

It's Pentax's advanced AF lens, just like Canon's L-head, commonly known as star mirror.

"limited"

Having high-performance and high-grade lenses is a special term given by Pentax, and it is the most advanced lens product series in Pentax lens products. Limited edition.

SMC: super multilayer coating, English full name is Super Mluti Coating.

The lens marked "SMC" means that it adopts Pentax's unique lens coating technology, which helps to improve the image quality and has strong anti-glare ability.

Aspheric lens

An ideal lens should gather light at one point, but unfortunately there is nothing absolutely perfect in this world. Because the light passing through the center of ordinary spherical lens and the surrounding light can not converge to one point, the so-called spherical aberration is caused, which affects the imaging quality. Using aspheric lens can alleviate this phenomenon and effectively control spherical aberration. This technique is often used for wide-angle lenses. Pentax aspherical lenses are generally made of thermosetting resin.

Using aspherical lens in lens design can reduce the number of lenses, reduce the weight and volume, and provide better optical performance. Aspheric lenses are generally used to solve the problems of glare and edge deformation in wide-angle and zoom lenses, and can also improve the optical quality in telephoto lenses.

Ultra-low dispersion low dispersion glass

Because natural light is not composed of light of a single color, when it is refracted in glass, the imaging of various monochromatic lights is different because of the different refractive indexes of various lights. Pentax uses ultra-low dispersion on some advanced FA* lenses to minimize the influence of dispersion, thus greatly improving the imaging quality of telephoto lenses.

IF (internal focus) internal focus

InnerFocus technology is mainly used in high-end lenses. When focusing, only a part of the lens group inside the lens moves as a whole to achieve focusing. This kind of lens is characterized by constant length, high speed and no rotation of the front lens, which is beneficial to the installation of the filter. At the same time, the shortest shooting distance can be shortened.

Electric zoom

PowerZoom is a remarkable feature of Pentax KAF2 bayonet lens. The lens has a built-in zoom motor, which can replace manual zoom and has three zoom speeds. Although some people are not optimistic about this zoom mechanism, it can easily create some interesting effects, such as zooming while opening the shutter to make the picture "explode", or keeping the size of the tracked object unchanged by electric zooming during translation. The biggest disadvantage of electric zoom is power consumption. If you want to use electric zoom, the best way is to have a battery box.

AF/MF full range switching

Photographers who have used Pentax FA* will be very satisfied with its convenient AF/MF switch. Generally, telephoto lenses often have an AF/MF conversion device on the lens body, so that the focusing mode can be controlled through this device instead of looking for the AF/MF conversion key on the body.

Nikon's lens has a small and thin ring. Turning it can change the focus mode, but unfortunately, before turning it, you must press the small metal button on the ring, and your hand must return to the focus ring to focus manually, which is time-consuming and troublesome when capturing. The whole switching action of Pentax is on the focus ring. Pull it back gently At this time, whether it is manual or automatic on the fuselage, it will immediately switch to manual mode for focusing, and push forward after use to restore the original mode. Another advantage is that when you rotate the focus ring beyond the scale during manual focusing, the focus ring will immediately separate from the mechanical device in the lens without damaging the mechanical structure of the lens. This one-button operation is very convenient for users, so you can switch the focus mode at any time, without having to look for any button on the body or mirror, and without worrying about hurting your baby because of misoperation. Perhaps because of the price problem, this mechanism, which is completely considered by users, only exists in FA* series lenses.

CF micro continuous focusing micro full macro

All focal lengths are focused directly to macro.

Meter (abbreviation for meter)) Minimum object distance closest focal length.

Pentax series a MF lens

Pentax -A* A series MF large aperture lens

Pentax F F series autofocus lens, the first generation autofocus lens

Pentax -F* F series AF large aperture lens, the first generation AF lens.

Pentax -FA FA series autofocus lens, the second generation autofocus lens.

Pentax -FA* FA series AF large aperture lens, the second generation AF lens.

Pentax -M M mm series MF lens

Pentax -M* M series MF large aperture lens

Soft focus lens

Third princess

Smc pentax -FA 3 1mm F 1.8AL limited edition,

Smc pentax-fa 43mm F 1.9 limited edition

Smc pentax -FA 77mm F 1.8 limited edition.

Three ultra-thin "cookie" lenses

Smc pentax -DA 2 1mm F3.2AL co., ltd,

Smc pentax-da 40mm F2.8 co., ltd.

Smc pentax -DA 70 mm F2.4 co., ltd.

Pentax lens explanation: A: A series manual focusing lens.

AF/MF: manual/autofocus switching.

Aluminum: aspherical lens.

CF macro: continue to focus on macro macro.

DA: DA lens is a special digital lens designed by Pentax for digital SLR cameras with APS-C format. It is marked with a green circle and cannot be used on Quan Huafu models.

Ed: ultra-low dispersion ultra-low dispersion lens.

F: Pentax's early autofocus lens mount.

FA: It is also Pentax's AF lens mount, which has two more electronic contacts than F mount.

If: interfocus internal focusing.

Limited edition: Limited edition lens is also Pentax high-performance and high-grade lens.

M: m series manual focusing lens.

Meter (abbreviation for meter)) Minimum object distance closest focal length.

PowerZoom: electric zoom.

SMC:Super Mluti coating super multi-layer coating, Pentax unique lens coating technology, strong anti-glare ability.

Soft focus: Soft focus lens.

SDM: ultrasonic motor

*: * Mirror is Pentax's advanced professional lens, just like Canon's L-head, commonly known as star mirror.

Examples show that the FA* 80-200 F2.8 ED lens represents Pentax professional star lens, with a focal length of 80-200mm, a constant maximum aperture of F2.8 and an ED ultra-low dispersion lens. FA3 1mm F 1.8al limited lens represents a limited edition lens, with a fixed focus of 3 1mm and an aperture of F 1.8, and an aspheric lens is adopted.

Make fun of the P lens group (excluding the digitally optimized DA head)

A ranger:

Easy, reasonable focal length, suitable for traveling around the world. It is said that the color is outstanding and there are free differences at both ends, but the zoom head is inevitable, but the price is slightly higher (above 3000), and it is said that it is not original (OEM product). ...

This will be named: civil zoom FA24-90/3.5-4.5 (instead of FA28-200).

Alex:

Alex was pregnant with P's old stunt Jack Power Zoom, but unfortunately, it was born at an untimely time and had power, because it was redundant, which led to weight gain and even high price (about 2500). In fact, the quality of 28- 105 is very good, and there is still a market. But if you have a special preference for jacks, these two are a good couple.

Civil electric zoom

FA28- 105/4-5.6PZ

FA 100-300/4.5-5.6PZ

Third princess

These three talents and looks are unique, as light as a swan. They come from towns in our country. The price is higher, but it is definitely worth marrying at least one. If you lose all your money, don't you envy killing heaven and man, just like Kang and LOGO of FB. ...

Limited edition fixed focus head

FA3 1/ 1.8LE

FA43/ 1.9LE

FA77/ 1.8LE

Four big scattered people (fair? )

These four men are flabby and incompetent, but they are all wearing bronze armor (pretending to be top-notch? Many of them are not locals (smuggled in), and they are also the products of Pentax's low-cost and low-quality route. Old Xi said it was cheap to buy dead people. ...

Civil zoom head:

FA28-80/3.5-5.6

FA80-200/4.7-5.6

F35-80/4-5.6

FA 100-300/4.7-5.8

Five lucky stars

Although these people are ugly, they are all very skilled, light and easy to use, especially the low price, which is really a blessing to the public in country P!

Civil fixed focus head

FA28/2.8

FA50/ 1.4

FA 135/2.8

Civil zoom lens

FA28-70/4

FA80-320/4.5-5.6 (few, some back doors are selected)

Five protectors

Five generals from country P, all with unique skills and excellent quality, are not cheap but fair.

Civil fixed focus head

FA35/2 (rare, data unknown)

FA20/2.8

FA 100/2.8MACRO

Civil zoom lens

FA 17-28/3.5-4.5 fisheye changes

FA20-35/4 wide-angle transformer

Unexpected misfortune

Long is good-long and short is so short.

Reflection 1000/ 1 1

One piece * 1200/8

M reflection 2000/ 13.5

A 15/3.5

16/2.8 fisheye

Six masters of Microsoft

Microsoft?

FA50/2.8

Fa100/2.8m

FA 100/3.5M

One *200/4M

FA28/2.8 soft

FA85/2.8 soft

Ten bailiffs

These ten men are dressed in golden armor, with good looks, outstanding martial arts and outstanding military achievements. Of course, the price is high. ...

Top fixed focal length head

FA*24/2

FA*85/ 1.4

FA*200/2.8

FA*300/4.5

FA*300/2.8

FA*400/5.6

FA*600/4

Top zoom lens

FA*28-70/2.8

FA*80-200/2.8

FA*250-600/5.6

DA mirror:

Wide angle:

Dayan10-17mm f3.5-4.5ed

Da12-24mm F4.0 ED/AL

DA 14 mm F2.8 ED

Da16-45mm F4 version

Da18-55mm F3.5-5.6

Da★16-50mm F2.8 ED AL [IF] SDM

Medium telephoto:

Large caliber 50-200mm F4 5.6 caliber

Da★16-50mm F2.8 ED AL [IF] SDM

"cookie head":

DA2 1/3.2

DA40/2.8

DA70/2.4

Structure.baiwei:

DFA 100/2.8 macro