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Question: Whats the difference between this flash and the Sony HVLF20AM TTL Digital Flash. I own NEX 6 and wondering which one is a good fit? Thanks
Document: Perfect match for NEX 6. Have been trying to buy the higher end Sony Flash. This is soooo good, I am having a difficult time justifying the bigger Flash!
That's right--you can shoot with shutter speeds all the way up to 1/4000! The normal high speed sync caveat applies--flash range is greatly reduced. And you are limited to one flash group, I think. But this combination delivers a capability that I didn't think the NEX-6 had, and I haven't found reference to anywhere else. Might work with other Sony flash combinations too.
This is a great little flash to supplement you small NEX camera and lenses. I bought it for my NEX 6 and find  that it's reliable, fact, and the TTL is accurate. Of course the head rotates but doesn't swivel. It cannot be fired remotely by the on-camera flash. I'm mostly and available light guy, but for bouncing light of the ceiling at a party or something like that it's the perfect tool.
This (very) small flash adds almost no weight or bulk to the NEX line of cameras, and it's twice as powerful as the built in flash. For those of us who want to travel light and compact, this is a very good choice.Used as direct flash it has TTL metering.
I use this flash on the NEX-6. It give you about 2-3 times the power of the built in flash, so it's not's super powerful, but works well for what it does. I would say it is good out to about 40 ft and I actually used it for a few shots in a wedding and it worked well.
Usage is simple, flip the flash down and it turns off. Flip it up and it turns on. I was able to get about 100 flash before the recharge time in between pictures began to get unbearable.There's a small turn dial for telescope flash, but I couldn't really tell the difference.It's more of a preference, but I would've have prefer if they engineered it where the flash can be powered from the NEX-6 built in battery instead of using 2-AAA battery.
The camera calculates a specific guide number for each photo based on the distance from the subject using ADI, along with ambient light and pre-flash reflectivity of the subject and the background using TTL metering, this insured proper white balance and even exposure.This is way stronger than the internal flash by far and extends the camera's capabilities even though the NEX-6 does well in low light, more light when properly applied, is usually better.
I can use this flash on the RX100 II, some of the newer NEX cameras and the new a7 / a7R bodies - finally one connector to rule them all (though it would be nice if Sony would use more metal and less plastic in the shoe connector of the accessories).
I bought this flash to go with my Sony DSC-HX50V/B 20.4MP Digital Camera and was hoping I didn't need any attachments or have issues attaching the flash. I have had none and it works fantastic. I use this for personal use and mainly pictures of my kids and a ton of family. It works much better than the flash that is on the camera. So far, so good. Will update if I start running into issues.
Full disclosure, I recently moved from Nikon DSLRs to the Sony NEX format. I did it for size. As good as my Nikon D300 was, I hardly ever took it out because it was like carrying a brick around  my neck.This speedlight is perfect. It is MUCH smaller than  the standard DSLR speedlights. The on/off is integrated into the hing where you can fold down the light. So, you fold it up and it's on, fold it back down and it turns off.
Answer: The HVLF20AM flash was designed to interface with the Alpha series cameras hence, the A designation. It lacks  Sony's new Multi Interface shoe (hence the MI designation for this flash) that communicates directly with the NEX-6 to provide true  TTL/ADI (through the lens)/(Advanced Distance Integration) flash metering. The HVLF20AM was never designed to work directly with the NEX 6 without the use of ADP-MMA adapter which allows the flash to mount on an NEX-6 but does not provide distance information to the flash so you loose  TTL/ADI flash metering capability. The base of these flashes looks entirely different with the HVLF20AM having 4 contacts in the center of it's shoe which was the standard for the Alpha series cameras and the HVLF20M MI shoe has a single center contact with 9 additional gold contacts at the front of the shoe which communicate with the Multi Interface shoe of the camera. I did have customer images posted that showed detailed pictures of the shoe and it's delicate contacts but Amazon has done away with all customer images and so you will have to look elsewhere to find pictures of the base of these flashes. So, the best flash for your Sony NEX-6 is the very flash Sony designed specifically for it, the HVLF20M MI. If you have any other questions don't hesitate to ask.