icon FieldMonitor: FAQ copyright © 2017 Adam J. Wilt  
A wireless video monitor for iPhone

What is the image resolution?

Teradek sources: depending on Teradek settings, anywhere from 480i to 1080p, 4:2:0, 8-bit.

Panasonic sources: 640x480 maximum; 640x360 for 16x9 images. Images are received as 8-bit JPEGs. Some cameras, including the LX100, drop to half-resolution while recording.

Is monitoring real-time?

With a GH4 and an iPad Air, I measured 100 milliseconds of latency: the image on the iPad is about 2–3 frames (at 24fps) behind the image on the flip-out monitor, though on occasion I've see only one frame of delay and other times as much as five frames. By comparison, 100 msec is better than a GH5 connected to a SmallHD 502 by HDMI.

Wi-Fi links are subject to variable latency and image loss due to interference and network congestion, so I can't guarantee a specific level of performance under all operating conditions. In general, my experience has been that the image transmission (sent over UDP) is quite robust, succeeding even when camera control (sent over TCP) times out. Even so, in high-traffic environments, frames can get dropped and image updating can stall for some time; Wi-Fi monitoring and control—whether using FieldMonitor, Image App (for Panasonics), or TeraCentral or VUER (for Teradeks)—is entirely dependent on the quality and speed of the wireless connection.

Is this the same thing as Wi-Fi WFM?

Yes. Wi-Fi WFM evolved into FieldMonitor. Updating Wi-Fi WFM will turn it into FieldMonitor.

What about a version for Bolt or Paralinx transmitters?

Bolt and Paralinx send low-latency uncompressed video over the 5GHz frequency band, but they don’t use Wi-Fi signaling, so their signals can’t be received by iDevices. And even if they could, the data rates would be scandalous.

Some crews simply connect a Cube to the output of a Bolt or Paralinx receiver, and rebroadcast the video for iPhones ‘n’ iPads.

Will you support other Wi-Fi-enabled cameras and transmitters?

I plan to add support for Sony hybrid camera (A7 series, a6000 series, etc.) in the near term. Beyond that, a lot depends on whether the camera has a published wireless interface, and whether it transmits video in a form that iDevices can decode. Japanese camera companies are very conservative and don’t like to expose their communications interfaces to third parties, so I can’t promise anything or suggest a timeframe when—if ever—support might occur for any particular class of camera.

Teradek supplies an iOS SDK (software development kit) with code to discover and connect to Teradek Cube, Clip, and VidiU transmitters and decode their streams. Support for newer Teradeks, like Serv and Serv Pro, will require an update to the SDK that’s aware of the newer devices.

Note: Panasonic’s remote interface isn’t published, but its HTTP commands are unencrypted, so the basic interface was easily reverse-engineered by clever folks at personal-view.com. Once I saw that, it only took a few weeks of looking at wireless traffic to suss out enough to make the GH4 and GH5 work. However if Panasonic ever decides to change their protocol and encrypt it, all third-party apps will stop functioning. There is no guarantee that such changes will be reverse-engineerable; if the signal is encrypted and the protocol changes, it is likely that no third-party apps will ever work again.

There’s only one “settings button”; there’s no false-color control!

You have an older iDevice that doesn't support false color. False color requires iPhone 5S or later, iPod touch 6G or later, iPad Air or later, iPad mini 2 or later, or iPad Pro.

Where is the Android version?

I don't have one, sorry. I’m busy with iOS work, and besides, there is no Teradek SDK for Android.

I'm a student: can I get a discount?

FieldMonitor is available through Apple’s Volume Purchase Program for education. Your school can buy 20 or more at half price, and give you a code to install it on your iDevice.

Sadly there’s no good online description of the Volume Purchase Program at present, though it’s briefly mentioned here, under “Apps at a volume discount”, and there's some deployment info here. For more details, contact the Apple technology manager or IT folks at your school.

Who needs to see YCbCr WFMs?

I've never needed it myself, but Alex Lindsay said it was essential. So there it is. Who am I to argue with Alex Lindsay?  :-)

Why isn’t my question answered here?

Because I haven’t heard it yet, that's why. Ask me and I’ll see if I can answer it.

© 2017 Adam J. Wilt.  Last updated 2017.05.22