外置闪光灯⽩玩了，原来E-TTL模式还可以这样玩如何玩转E-TTL，其实不能算是闪光灯的基础知识，应该算是⼊门对闪光灯的使⽤多少有所了解以后的知识了。
所谓的E-TTL，也就是闪光灯通过镜头测光由相机决定闪光灯的输出量。
那么，这个输出量是多少呢？你不知道，我也不知道，只有⼀个最后的曝光结果给我们看。
曝光不⾜或者曝光过量的原因是什么，我们都不知道，因为闪光灯没有给我们⼀个确切的输出值。
这⼀点也就是为什么建议初学闪光灯的使⽤者，⼀定要从⼿动曝光开始，⼿动控制闪光灯的输出值，1/1、1/2、1/4、1/8、1/16、1/32、1/64、1/128，⼀共7档的输出量供您选择，每档之间还可以调整1/3的步长。
曝光不⾜了，您可以提⾼闪光灯的输出值⼀档，曝光过了，您可以减⼀档。
总之，您可以慢慢的调整，直到找到合适的输出值为⾄。
但是，凡事都有⼀个但是。
⼿动曝光这么好，⼚家为什么花费巨资研究出E-TTL来呢？原因就在于，很多时候，不允许您慢条斯理的寻找您的合适的输出功率。
⽽且，很多时候，被摄主体在不断的移动之中，场景在不断的转换之中，⼿动控制闪光灯？除⾮您是疯⼦或者您就是传说中的“灯神”！E-TTL就是要的⾃动要的快速要的准确，我们⼀定要相信⼚家的能⼒，这个玩意绝对不是⽩给的！这也是为什么原⼚灯价格这么贵的原因，贵总是有理由的！那么，是不是把闪光灯插在相机热靴上打开，就⼀切OK了呢？很不幸，事实总是⾮常残酷的，您还需要了解⼀些东西，掌握⼀些东西，才能⼀切OK。
现在，让⽼格给你揭开E-TTL的神秘⾯纱，给您揭⽰⼀些⼚家说明书中没有的东西。
⽼格尽量⽤通俗易懂的语⾔结合图⽚来说明，如果您说还是没有看懂，请您拿起您的相机，把您的闪光灯插上，实验⼀下。
演⽰相机：佳能5D2 演⽰闪光灯：佳能580 2代使⽤镜头：蔡司50/1.4 ZE 闪光灯裸灯演⽰图⽚快门速度1/200秒，感光度100，排除现场环境光的影响，只测量闪光灯的数据。
User Manual®The All-Round Flashlight ExpertMH10Features·Utilizes a CREE XM-L2 U2 LED·Maximum output of up to 1000 lumens·Integrated “Precision Digital Optics Technology” provides extreme reflector performance·Boasts a peak beam intensity of 13,500 cd and a throw distance of up to 232 meters·Innovative single button offers access to four brightness levels and three special modes·High efficiency constant current circuit provides max runtime of 520 hours ·Integrated power indicator light displays remaining battery power (patented)·Power indicator’s secondary function displays battery voltage (accurate to 0.1V)·Charging module with a micro USB port charges Li-ion batteries rapidly ·Direct access to ultra-low output·Reverse polarity protection prevents damage from incorrectly inserted batteries ·Constructed from aero grade aluminum alloy with HAIII military grade hard-anodized finish·Waterproof in accordance to IPX-8 (two meters submersible)·Impact resistant to 1.5 meters ·Tail stand capabilityDimensionsLength: 130mm (5.12”)Head diameter: 25.4mm (1”)Tube diameter: 25.4mm (1”)Weight : 75g (2.65oz)(without battery)brightness level, simply release the switch when that level is being displayed. This mode has memory effect to ensure direct access to the previously used brightness level when the MH10 is resumed.Direct access to ultra-lowWith the MH10 switched off, press and hold the switch for more than 1 second to enter ultra-low output (1 lumen);Note: When in high output, the MH10 will reduce output luminance automatically after 5 minutes of use to prevent overheating and extend battery longevity.Special Modes (Strobe/SOS/Location Beacon)Press the switch twice in quick succession in any state to enter strobe mode. When in strobe mode, press and hold the switch for more than 1 second to cycle through SOS, location beacon and strobe modes. To exit, simply press the switch again. The MH10 does not have memory effect in any of these special modes.Charging FunctionThe MH10 is capable of charging one 18650 Li-ion battery with the included USB charging cable. Connect the USB cable to the MH10's charging port and a powersource (USB chargers, PC or other power terminals) as shown in the adjacent image.Fully charging one depleted 18650 battery takes approximately 6 hours.Thanks for purchasing NITECORE!Output & RuntimeNOTICEThe stated data has been measured in accordance with the international flashlight testing standards ANSI/NEMA FL1, using 1xNitecore 18650 battery (3.7V, 2600mAh) or 2xNitecore CR123 batteries (3V, 1700mAh) underlaboratory conditions. The data may vary in real-world use due to different battery use or environmental conditions.NITECORE (SYSMAX) is a member of PLATO, participating in and helping to develop the ANSI FL1 standard of measurement. Product testing data is in accordance with Operating InstructionsBattery installationInsert 1x18650 battery or 2xCR123 batteries as illustrated.Note: After loading batteries, the bluevoltage.Please refer to “Power Tips” section of this manual for details.WARNING1. Ensure batteries are inserted with the MH10 will not be operational with incorrectly inserted batteries.SYSMAX Industry Co., Ltd.TEL: +86-20-83862000 FAX: +86-20-83882723 E-mail: *****************Web: Address ： Rm1401-03, Glorious Tower, 850 East Dongfeng Road,Guangzhou, China 510600Changing /Charging BatteryBatteries should be recharged or replaced when any of the followings occurs: The power indicator blinks rapidly, output appears to be dim or the flashlight becomes unresponsive.MaintenanceEvery 6 months, threads should be wiped with a clean cloth followed by a thin coating of silicon-based lubricant.Warranty ServiceAll NITECORE® products are warranted for quality. Any DOA/defective product can be exchanged for a replacement through a local distributor/dealer within the 15 days of purchase. After 15 days, all defective / malfunctioning NITECORE® products can be repaired free of charge for a period of 60 months (5 years) from the date ofpurchase. Beyond 60 months (5 years), a limited warranty applies, covering the cost of labor and maintenance, but not the cost of accessories or replacement parts.The warranty is nullified in all of the following situations:1. The product(s) is/are broken down, reconstructed and/or modified by unauthorized parties.2. The product(s) is/are damaged through improper use.3. The product(s) is/are damaged by leakage of batteries.For the latest information on NITECORE® products and services, please contact a localNITECORE®**********************************************.The Nitecore official website shall prevail in case of any product data changes.Please follow our facebook for more info: NITECORE Flashlights4.2V3.5V3.7V 3.9V Full powerLow powerFull power Low power1 x 18650 battery2 x CR123 batteriesHIGHMIDLOWLUMENS240LUMENS1000LUMENS70LUMEN11h 15min28h 6hLOWER520h 5h 15min300h20h1h232m (Beam Distance)13500cd (Peak Beam Intensity)IPX-8, 2m (Waterproof AND Submersible)1.5m (Impact Resistant)1×186502×CR12320150112AccessoriesNitecore NL183 battery, USB charging cable, holster, clip, lanyard, spare USB port cover, spare O-ringleft unused for extended periods of time, Nitecore recommends all batteries are removed to prevent accidental activation of the flashlight or battery leakage.ON/OFFTo switch ON: Press the switch until a click is heardTo switch OFF: Press the switch once again until a click is heardBrightness LevelsWith the MH10 switched on, press and hold the switch for more than 0.5 second to cycle through brightness levels of ultra-low, low, medium and high. To select a desiredUnder normal charging conditions, the blue power indicator light will illuminate steadily to notify users. When charging is complete, the MH10 will terminate the charging process automatically and the blue power indicator goes out.Power Tips1. When the light is on, the power indicator will blink once every two seconds when power level drops to 50%; the power indicator will blink quickly when power level is low.2. After battery installation, the blue power indicator will blink to indicate battery voltage (accurate to 0.1V). For example, when battery voltage is at 4.2V, the blue power indicator will blink 4 times, followed by a one second pause and another 2blinks. Different voltages represent the corresponding remaining battery power levels:。
