Adding Dual Card to the Sony A7s II with Atomos Ninja Star
Regardless of what you shoot, it’s likely that it would be expensive, impractical, or possibly impossible to replicate should footage get lost.
It’s recurring nightmare of the film maker and one of those perils that we just would all rather not think about. Enter the Atomos Ninja star as a simple solution.
The Ninja Star by Atomos is of course intended as primarily a device to get footage with less compression and a more edit-friendly codec. It also as an aside allows for > 30 minutes of recording, though the Open Memories hack is a good option for this as well.
The purpose we have however is getting a redundant backup recording of anything we shoot.
The Ninja Star automatically starts/stops with the camera’s record function and it weighs nearly nothing which makes it a fairly small compromise for those wanting to keep the gear to a minimum. Personally, I am still looking forward to the a7s line to get built-in dual card but for now this is a tolerable work around.
The most important thing to know is that the Ninja Star can only record HD and only up to 30fps. That being said, it CAN record a backup track even if you’re shooting at a frame rate it doesn’t necessarily support.
For example, I shoot a lot of 60fps footage at weddings. By setting the Ninja Star to the default “Lock” setting, you’ll get 30fps interlaced footage on the Ninja Star. You won’t be able to use it the same way as the original footage, but you’ll have footage that is very usable. For weddings, that’s peace of mind enough.
On the flip side, if you use 30p or 24p as your acquisition format on the camera, you’ll be able to get exactly that on the Ninja Star. For the 24p setting to work correctly on the A7s II you’ll need to set the Ninja star to the i – 24p setting. For 30p, you’ll want the i->p setting.
So to review, if you’re using he A7s II and want to use this as a backup recorder:
60 fps on A7s = LOCK on Ninja Star
30 fps on a7s = i-P on Ninja Star
24 fps on a7s = i-24p on Ninja Star
If you don’t get the setting right, you’ll notice interlacing artifacts right away (lines in movement).
So there you have it. Mount the Ninja Star on top of your camera, get a 128gb CFast card (not the 64, too small) and set the Codec to the Prores LT. Keep in mind that Prores LT is about 3x the size of the internal codec so roughly 32gb of SD card space is going to mean a full CFast card.
It’s not perfect, but until Atomos releases a new Ninja Star type device with 4K and 60fps support (and preferably an SSD or similar media) OR Sony releases a proper dual card camera, this is not a bad compromise.