22C-D045A103

22C-D045A103

22C-D045A103

22C-D045A103

相机自动对焦一般情况下都不错。不过，在某些环境下你可能需要切换到手动对焦。有时相机反复检测也找不到准确的对焦点，比如物体反差较低，或者透过玻璃拍摄之类。

在摄影器材的发展过程中，大多数地方都越来越好，只有一样退化了：老式的手动相机有各种各样的对焦屏来帮助手动对焦。在这个所有相机都有自动对焦系统的时代，手动对焦屏已经不复存在。这意味着现在使用手动对焦比过去要困难一些。如果你的相机有实时取景功能，你可以用它来放大画面，辅助手动对焦。

内部/外部对焦

镜头的对焦方式有两种：内部及外部。它们的区别很简单：对焦时前镜组会动的是外对焦；前镜组保持不动的就是内对焦。

如果你使用镜头滤镜，就会知道有些滤镜依赖于旋转角度工作（比如偏振镜）。如果镜头在对焦时会转动，你就需要先对焦，再调整滤镜。除此之外，没有理由拒绝外对焦镜头。

Westinghouse 100 Amp Bus Plug Fusible Switch ITAPN363HG

Square D I-Line Breaker LC36600 600Amp A 600A 600

GE General Electric Breaker TEB TEB111040 40Amp A 40A

Westinghouse 100 Amp Bus Plug Fusible Switch ITAP363H

Orion Ormec ORN-50/AFEHS ServoWire Servo Controller

GE General Electric Breaker TED TED124020 20Amp A 20A

Omron S82J-6524 24V/2.1A Power Supply S82J6524

Mettler Toledo Masstron model 8141 Scale Readout Panel

Southern Transformer 7.5 kVA 480/277 V 7.5kVA 1 PH

Square D 120R-202 Current Transformer CT 2000:5 A Amps

Cutler Hammer IDT 542L PanelMate Series 500 92-01404-00

Siemens Tiastar 60A/20A MCC Double/Dual Feeder Bucket

GE Spectra RMS SKLA36AT0800 800 Amp 800A A SRPK800A800

Siemens Tiastar 125A/125A MCC Double/Dual Feeder Bucket

Onan 1200 A Amp Bypass Transfer Switch ATS 480V BT 1200

IT CT 140-602 Current Transformer 6000:5 A 8.25" Window

Square D Circuit Breaker KAL KAL36225 225Amp A 225 Amp

Square D QED I-Line PanelBoard 4000 Amp 3000A 480Y/277

RP Adams Automatic Water Strainer VWS 150 PSI 3080 GPM

Sti MS45D-2-AC MicroSafe MC42D Series Controller

Adaptive E9920-1112 DIN Mounting Processor E99201112

Square D 3750/4688 kVA 12470 480 Y/277 Padmount 2000

Benshaw CFRSD6SB548012 5 HP Solid Stare Starter 7.6A

Adaptive E9920-1113 DIN Mounting PSU Power Supply

Adaptive E9920-1114 DIN Mounting 8 bit Input E99201114

Allen Bradley AB 1336F-BRF100 VS Drive MCC Bucket 30A

Allen Bradley AB 1336F-BRF200 VS Drive MCC Bucket 60A

Allen Bradley AB 1336S-BRF100 VS Drive MCC Bucket 30A

Westinghouse Breaker JB JB2200W 200Amp A 200A 200 Amp

Allen Bradley AB 1336F-BRF200 VS Drive MCC Bucket 50A

Westinghouse Breaker JD JD2250F 200Amp 200 Amp 200A A

Carlo Gavazzi RZ4855HAP0 Panel Mount Relay

Foxboro E17DES-ISH2 d/p Cell Electronic Transmitter

Westinghouse Breaker LB LB2400F 400Amp A 400A 400 Amp

Allen Bradley AB 1336S-BRF50 VS Drive MCC Bucket 15A

Fuji PYX-9 Termperature Controller PYX9 Temp Control

Square D I-Line FA14020C FA-14020C 20 Amp 20A 20Amp A

Telemecanique Altivar 66 ATV66D79N4 AC Drive 75HP/100HP

Simpson H235-1-0710-0-2?-1 Hawk II 2 Advanced Digital

Fanuc Robotics 6 Axis Brake Release Unit 244-211A-01

Furnas System 89 Size 1 Breaker Type Starter MCC Bucket

Volgen PSN-122R1 12V 2.1A Power Supply PS PSN122R1

Furnas System 89 Size 1 Breaker Type Starter MCC Bucket

Precision Digital PD750-3-14 Temperature Meter PD750314

Allen Bradley AB 150-A35NBDB SMC MCC Bucket 50A 20 HP

Omron CQM1-LK501 I/O Link Unit CQM1LK501

Allen Bradley 1336-RFB-7-A Input RFI Filter AB

MagneTek MCR Constant Voltage Power Conditioner 3560910

Cutler Hammer HFD 65k HFD2020 20 Amp 20A A

Cutler Hammer Breaker HFD HFD3030L 30A A 30Amp 30 Amp