Sony Announces Full-Frame Low Light A7s with 4K Output at NAB 2014

Updated: April 8, 2014

The A7s is a pretty big deal for Sony: it marks their first still camera with the ability to record 4K. The Alpha 7s was announced this week at the low-key NAB show in Las Vegas.

The A7 is based off of the same body found in the A7 and A7R, but on the inside, the A7s is a bit different. The A7s houses a lower-resolution 12-megapixel sensor, but is still full-frame. This 12 megapixel Exmor CSMOS is combined with Sony’s own BIONZ X image processor, giving a huge sensitivity range of ISO 50 – 409600. This brings what makes this camera special: the ability to shoot 4K video in almost utter darkness. However, this feature comes with a limitation: only being able to store 1080p video internally. For all the 4K videos you’re going to shoot, you’ll need to attach the camera with an external drive. This comes off as a bit disappointing, because Panasonic’s Lunix DMC-GH4, Sony’s to-be competition, can store 4K internally.

Sony also says that the A7s is the first camera that uses the entire with of the sensor for 4K video recording, thus allowing recorders to unlock all of the sensor’s features. But, a comparison to the GH4 again, the A7s only does 8-bit 4:2:2 capture, versus the GH4’s 10-bit capture. However, the larger 35.8×23.9 mm sensor in Sony’s A7s should allow for a better total range over the GH4 (which has a 17.3×13 mm sensor), even if does use Sony’s lower-end AF contrast system.

And as for codecs, Sony has included the XAC S format, along with our usual suite of AVCHD and MP4. The XAC S format allows for HD recording at a 50 MBPS data rate using a lower compression.

Sony hasn’t released pricing information at this time, but we are expecting around $2,500.

Source: Engadget