6SL3352-1AE33-8AA1

6SL3352-1AE33-8AA1

6SL3352-1AE33-8AA1

可变光圈镜头是指大光圈会随焦距变化的变焦镜头。回想一下什么是光圈：允许光线通过的光孔，用焦距的倒数来表示。所以，100mm焦距镜头f/2.0光圈表示孔径是50mm（译注：应为入瞳直径）。

让我们对28-135mm f/3.5-5.6镜头做一个数学计算。在28mm，你可以使用f/3.5光圈，28/3.5=8mm.当我们变焦到135mm，大光圈是f/5.6，孔径是135/5.6=24mm。

那为什么不能做成恒定f/3.5的光圈呢？在135mm端，f/3.5需要38mm孔径，为了控制镜头的体积，所以不能做出这么大的光圈。

可变光圈不好吗？

很多所谓的“专业”摄影师不愿意用可变光圈镜头，但其实并没有什么理由应该如此：可变光圈是一种妥协，但所有镜头设计都是妥协。与恒定光圈镜头相比

6ES7414-2XK05-0AB0

 S7-400 CPU 414-2 DP

6ES7414-2XJ00-0AB0

6ES7414-2XJ01-0AB0

 S7-400 CPU 414-3

6ES7414-3XJ00-0AB0

6ES7414-3XJ04-0AB0

6ES7414-3XM05-0AB0

 S7-400 CPU 414-3 PN/DP

6ES7414-3EM05-0AB0

 S7-400 CPU 416-1

6ES7416-1XJ02-0AB0

 S7-400 CPU 416-2

6ES7416-2XL01-0AB0

6ES7416-2XL00-0AB0

 S7-400 CPU 416-2

6ES7416-2XK00-0AB0

6ES7416-2XK01-0AB0

6ES7416-2XK02-0AB0

6ES7416-2XK04-0AB0

6ES7416-2XN05-0AB0

 S7-400 CPU 416-3

6ES7416-3XL00-0AB0

 S7-400 CPU 416-3

6ES7416-3XR05-0AB0

 S7-400 CPU 416-3 PN/DP

6ES7416-3ER05-0AB0

 S7-400 CPU 416F-2

6ES7416-2FN05-0AB0

 S7-400 CPU416F-3 PN/DP

6ES7416-3FR05-0AB0

 S7-400 ER1 Exp. Rack

6ES7403-1TA01-0AA0

 S7-400 FM 450-1 counter card

6ES7450-1AP00-0AE0

 S7-400 FM 451 Positioning module 3 channels

6ES7451-3AL00-0AE0

 S7-400 FM 453 Positioning module

6ES7453-3AH00-0AE0

 S7-400 Front connector with Twisted ribbon cable connection

6ES7921-4AB00-0AA0

 S7-400 Frontconnector 48pin scre-type contact

6ES7492-1AL00-0AA0

 S7-400 Frontconnector 48pin, spring contact

6ES7492-1BL00-0AA0

 S7-400 IM463-2

6ES7463-2AA00-0AA0

 S7-400 Interface module RS422/RS485

6ES7963-3AA00-0AA0

 S7-400 Interface module TTY

6ES7963-2AA00-0AA0

 S7-400 PS 10A 120/230VAC

6ES7407-0KA02-0AA0

6ES7407-0KA01-0AA0

6ES7407-0KA00-0AA0

 S7-400 PS 20A 120/230VAC

6ES7407-0RA01-0AA0

 S7-400 PS 4A 120/230VAC

6ES7407-0DA02-0AA0

 S7-400 PS405 10A 24VDC

6ES7405-0KA02-0AA0

6ES7405-0KA01-0AA0

 S7-400 PS405 20A 24VDC

6ES7405-0RA00-0AA0

 S7-400 PS405 4A 24VDC

6ES7405-0DA02-0AA0

6ES7405-0DA01-0AA0

6ES7405-0DA00-0AA0

 S7-400 Rack

6ES7400-1JA01-0AA0

 S7-400 Rack

6ES7400-1TA01-0AA0

6ES7400-1TA00-0AA0

 S7-400 SM431 16AI U/I/Resist/Thermo/Pt100 isolated

6ES7431-7QH00-0AB0

 S7-400 Terminator for IM461

6ES7461-0AA00-7AA0

 S7-400 Terminator for Receiver IM461-1

6ES7461-1BA00-7AA0

 S7-400 Terminator for Receiver IM461-3

6ES7461-3AA00-7AA0

 S7-400H CPU 412-3H

6ES7412-3HJ14-0AB0

 S7-400H CPU 414H

6ES7414-4HM14-0AB0

，可变光圈镜头有一些很明显的优势：它们更轻，更小，而且便宜得多。

6SL3352-1AE33-8AA1  

Yaskawa CIMR-DS Varispeed 340 Diod Power Unit CIMRDS

Yaskawa CIMR-G5V20P4 0.75HP VariSpeed 616G5 CIMRG5V20P4

Yaskawa CIMR-3.7B.E04 230V Series AC Drive CIMR3.7B.E0

Yaskawa CIMR-2.2B.T 230V Series AC Drive CIMR2.2B.T

Yaskawa CIMR-37B.T 230V Series AC Drive CIMR37B.T

Yaskawa CIMR-G5V22P2 11A VariSpeed 616G5 CIMRG5V22P2

Yaskawa CIMR-0.75B.T 230V Series AC Drive CIMR-0.75 B.T

Yaskawa CIMR-55WSB 80kVA Varispeed 676 CIMR55WSB 200V B

Yaskawa CIMR-3.7B.T 230V series AC Drive CIMR3.7B.T

Yaskawa NPSO-1203L 300V 120A Diode Converter NPSO1203L

Yaskawa CIMR-G3V20P4 0.5HP 200V Inverter CIMRG3V20P4

Yaskawa CDBR-2022 200V for 22kW Braking Unit CDBR2022

Yaskawa CIMR-7.5WS.P 10kVA Varispeed 676 Inverter Drive

Yaskawa CIMR-3.7WS.P 5kVA Varispeed 676 Inverter Drive

Telemecanique Altivar 71 ATV71HU30M3 AC Drive 4 HP NIB

Yaskawa CDBR-22HT Brake Unit CDBR22HT EOJ502640

Yaskawa CIMR-XCBA40P7 2.6kVA 3.4A VS Mini CIMRXCBA40P7

Honeywell ISSC 621-9930 Parallel I/O Module 6219930

Square D QMB3660 Saflex Panelboard Switch 600 Amp A QMB

Square D QMB Branch Switch 30 Amp QMB361HW Fusible 600V

Square D QMB Branch Switch 100-30 Amp A QMB363T31W 600V

Square D QMB364 Branch Switch 200 Amp A QMB-364 600V

Square D QMB3640 Saflex Panelboard Switch 400 Amp A QMB

Square D QMB3640 Saflex Panelboard Switch 400 Amp A QMB

Square D QMB Branch Switch 400 Amp QMB365W 600V Fusible

Square D QMB3640 Saflex Panelboard Switch 400 Amp A QMB

Square D QMB Branch Switch 30 Amp QMB321HW Fusible

Square D QMB Branch Switch 60 Amp QMB322HW Fusible

Square D QMB Branch Switch 100 Amp QMB323TW Fusible

Allen Bradley AB Size Sz 1 Fused Reversing MCC Bucket 

GE Type RSL 5000/7000 kVA 13200 4160 Y/2400 Padmount

MGM Transformer 300 kVA 300kVA 480/208Y/120 V 208 Dry Y

GE Transformer 275kVA 460/230Y/133 V 275 kVA 3 PH 230 Y

Square D I-Line Main Lug Panelboard 225 Amp 600 V 3P 4W

Square D 9422ATCF301 Disconnect Switch 30Amp 9422A1 NIB