There are some things to remember when doing remote video interviews. This piece was written nearly two years ago, but still valid when published in July 2017.
Number of participants and locations
The number of participants and how many locations they are situated at have an impact on the equipment you need.
If you want to have good sound and be more than one person at one location, you will need professional equipment, i.e. XLR microphones and multi channel mixers. More locations make it harder to see everybody at the same time and increase the requirement for bandwidth. You also need more advanced mixers and separate recording of each person to get as good result as possible.
Your internet connection may be a showstopper.
Two-way video conferance with ADSL is nothing to recommend. Down-stream speed is often OK, but upstream is not, as it's nearly always is to slow. We have tried, and there is a lot of lag if you run your video stream in HD quality. Mobile broadband is acceptable as you have the same speed in both directions, but you will probably run in to limitations imposed by your maximum data limit per month.
This leave us with fixed broadband for a good result if we want to stream video. However, there are some alternative routes.
Budget and prioritization
Unless you break the bank, you are likely to have budget constraints.
Use what you have, borrow from a friend and buy the most important things. This leads us to prioritization. Sound is more or less everything in interviews. If you have good sound, reasonable lightning and subject in focus, your home. If you spend your money, start with a separate microphone as this is the minimum level for a remote interview.
The two biggest players are Google with Hangouts or Microsoft with Skype. You need both. Skype for one-to-one interviews and Hangouts if you are many participants. Both programs have their pros and cons. To get everything to work, I would recommend a bit of black magic, as this still is bleeding edge technology.
Your choices for sound equipment are only limited by your wallet.
Your options are from a headset to your computer to a separate microphone connected to a mobile phone or professional microphones with a separate recorder and/or mixer. Whatever you do, don't use the built microphone in your computer, mobile or camera. Please, don't do this. You also need a pair of headphones to avoid disturbances.
Your choices for video equipment is more or less limited to what you can't do or shouldn't do.
You shall not use the built in webcam in your laptop, unless it's of a very high quality.
You can't use your mobile phone as a webcam to your computer, even if you can connect them physically via USB or Lightning adapter, due to lack of software support.
You can't connect your video camera or DSL via USB to your computer. You need to use either FireWire, HDMI or SDI output from your camera. The challenge is that nothing new uses FireWire, so you need to use HDMI or SDI instead. But, HDMI or SDI inputs are not standard on laptops and therefore you need an external converter with either USB3 or Thunderbolt.
In theory, Thunderbolt works with with both PC- and Macintosh laptops. In practice, Thunderbolt input only works reliable with newer Mac's. I have used Google hangouts myself in this fashion, but not tried Skype with Thunderbolt converters, so I can't say if this works well r not
The only remaining alternative if you want to do live recording is therefore a separate webcam that works with both Skype and Google hangouts.
But if you will send your video stream in HD-quality, then you need better than ADSL-connection. You also need a faster computer to avoid lag in streaming. Full 1080p streaming requires an Intel i7 CPU and for 720p will you need at least an i5 class CPU. SSD is the only reasonable alternative for storage. Physical discs, with rare exceptions, are not fast enough to save a countinous video stream.
If streaming from computer, you can either capture recording with Google Hangouts, or use an additional program with Skype. There are different programs for Windows or OS/X and no freeware as far as I know.
The alternative path, if you don't have a separate webcam and fast internet is to record locally at each site and edit later. What you need is a video capable smartphone with enough of storage (16Gb ain't, Apple), a small tripod with a holder for the phone and little bit of lightning.
You can then use your webcam for viewing the other person in a lower resolution and bit rate in order to see her body language. Remember the first bullet - Interview skills?
If you then connect a separate microphone to your smartphone and then use a pair of earbuds to listen to the other party, you will reach a basic quality level for your remote interview.
Just two caveats to remember.
1. Limit each recording session so that they not are longer than 20 minutes and file size should be less than 4 Gbyte for each clip.
2. Video and sound are not in sync when recording with Android phones, so you must be able to fix in edit.
My recommendation for casual remote recordings is to use an iPhone 5s (or newer) with 64 Gb memory and a Røde SmartLav+. The alternative is to use a Logitech HD-capable webcam with a Sennheiser headset connected to your computer.
What do I use myself?
The obvious alternative is to use my iPhone 5s, a small Gorilla-pod, a Røde SmartLav+, a Sennheiser headset and a Lenovo X220 laptop running Skype or Google Hangouts. Recording done locally and the internal web-cam used for viewing other person only.
The other approach is to bring in the heavy artillery. Sony video cameras on tripods, 13 " MacBook Pro with BlackMagic Design HDMI-> Thunderbolt converter, suitable XLR-microphones with a field recorder and/or multi channel mixer. Works with with both streaming to others & recoding via Google Hangouts, local recording with Skype and recording for later editing at the same time.
Best alternative for multi-cam edit with low budget right now is Final Cut Pro/X, even if you could use Adobe Premiere or Avid.