The Elphel Camera
The Elphel camera
Apertus is using the Elphel 353 free software and open hardware camera, you can find more informations about it here : www.elphel.com
Technical Specs:
Sensor:
The camera uses an Aptina CMOS bayer-pattern sensor with an optical format of 1/2.5" (5.70mm x 4.28mm) and a native resolution of 2592x1944 (5 Megapixels). It features a 12 bit ADC and supports: region of interest, on-chip binning and decimation. Aptina claims that the chip has 70db of dynamic range at full resolution and 76db when using 2x2 binning.
Lens Mount:
The camera has a standard C-mount but ships with an adapter ring that allows to mount CS-lenses as well. More adapters are in planning stage.
Resolutions:
The recording resolution can be freely adjusted to anything starting from 16x16 to 2592x1944 in 16 pixel steps. This includes Apertus AMAX (2224x1251), Apertus CIMAX (2592x1120), 2K (2048 × 1536), Full HD (1920x1080), HD (1280x720) and of course all lower resolution SD formats like DV PAL, DV NTSC, etc.
The lower the resolution the higher the maximal possible framerate. At the full sensor size (5 million pixels or 5 Megapixels) the maximal frame rate is 10 fps in normal color mode and 15 fps in JP4 RAW mode. JP4 achieves higher framerates in general as some camera internal calculations are skipped and need to be applied later in postproduction (like debayering/demosaicing).
| Standard | Resolution | Record Mode | max. FPS |
|---|---|---|---|
| Apertus AMAX 16:9 | 2224x1264 | JP4 RAW | 24 |
| Apertus CIMAX 2.35:1 | 2592x1120 | JP4 RAW | 24.2 |
| Full HD (1080p) | 1920x1088 | RBG | 25.2 |
| Full HD (1080p) | 1920x1088 | JP4 RAW | 30.9 |
| 2K | 2048x1088 | RBG | 23.9 |
| 2K | 2048x1088 | JP4 RAW | 29.5 |
| HD (720p) | 1280x720 (2x2 binning) | RBG | 46.2 |
| HD (720p) | 1280x720 (2x2 binning) | JP4 RAW | 46.2 |
| HD (720p) | 1280x720 | RBG | 57.9 |
| HD (720p) | 1280x720 | JP4 RAW | 60 |
| NTSC DV | 640x480 | RBG / JP4 RAW | 126 |
| NTSC DV | 640x480 (3x3 binning) | RBG / JP4 RAW | 82 |
| NTSC 16:9 | 854x480 | RBG / JP4 RAW | 110 |
| PAL DV | 720x576 | RBG / JP4 RAW | 100 |
| PAL DV | 720x576 (3x3 binning) | RBG / JP4 RAW | 66 |
| PAL DV 16:9 | 1024x576 | RBG / JP4 RAW | 84 |
Raw Recording:
The RAW recording mode in Apertus is called JP4 RAW. Because certain in-camera compression steps can be skipped JP4 RAW allows higher recording speed resulting in more fps. JP4 RAW requires postprocessing (DNG Converter) but in return offers the highest possible image quality.
Connectors:
SATA: Can be used to connect any external SATA device that is supported under Linux (external harddrives, raids, etc.)
Ethernet: 100MBit Network with POE (48V)
USB: USB 1.1 with 5V power supply
IDE: Used to connect internal HDD
RS232: Access to Console and debug output
Recording Media:
- Optional internal IDE 1.8" HDD
- 2 internal CF Card Slots
- external SATA connector to connect any SATA device (Linux support required)