The $25 Raspberry Pi
Posted 06 February 2013 - 04:14 PM
Posted 06 February 2013 - 07:03 PM
The pixel pitch is so small 1.4um*1.4um thus BSI type is selected.
It can do 5M still or various format of continuous (motion picture) read-out.
I would not recommend using it for astro application except for very bright objects, i.e., solar system imaging.
P.S. IMHO, not a good fit for this astro video forum.
Posted 06 February 2013 - 09:57 PM
Posted 08 February 2013 - 07:26 AM
Posted 08 February 2013 - 08:23 AM
Posted 09 July 2013 - 08:34 AM
Posted 09 July 2013 - 08:40 PM
- OV5647 is not using the parallel bus (DVP mode) to send digital video to Rasp Pi's main ARM CPU but instead using the high-speed serial bus (MIPI's CSI-2 interface) to send to Rasp Pi's integrated SoC GPU Broadcom VideoCore IV (same package as in the CPU ARM11 core). Omnivision image system chip requires a NDA to get the full spec.
- Rasp Pi's GPU receives the digital video then compress down to H.264 in video mode
The firmware is close-sourced.
- OV5647's DPC module seems to be only doing Defect Pixel Correction, as opposed to similar chip OV5642's image processing module (can perform simple compression as well)
- OV5647 can do 2x2 binning on the like-color pixels. Binning, oddly, is stated as voltage averaging (not using the term "summing") which happens before A/D conversion. It does not state it is summing in charge domain but already in Q -> V converted voltage values in voltage level. As a purist, charge-domain summing is better.
- However, in RaspPi wiki of the camera module, the functions of: windowed capture, binning mode, etc. are not exposed to be user controllable.
My view, I wouldn't spend time further on it.
There are more exciting image systems out there.