High Dynamic Range (HDR) is a feature available on the PL-D753 (IMX421) and PL-D757 (IMX420); HDR uses the new Dual ADC feature of the 3rd generation Sony Pregius sensors, to read out each pixel with two different gains: 0dB and 12dB.
Users can choose between two HDR modes: On-Camera, and Interleaved. These modes can be enabled from the HDR Mode drop down menu, found in the Controls tab of Pixelink Capture:
When On-Camera HDR is enabled, the low gain and high gain images are combined on camera, to create a single image with a higher dynamic range. This allows more details to be seen in the bright areas of the image, which may otherwise be lost due to over-saturation; As well as more detail in the dark areas of the image, which may not otherwise be visible. This can provide up to an additional 6-10dB of dynamic range.
In this mode, both the low (0dB) gain and high (12 dB) gain frames are passed to the host, allowing you to do any desired image processing with the frames.
Please note: As each row of pixels is read out twice, and therefore two frames are passed to the host, the image received by the host will therefore be twice as wide as a "normal" (non-HDR) image. And as with On-Camera HDR, the maximum frame rate will be reduced by half.
Please note: Interleaved HDR mode is not compatible with the YUV422 pixel format. For colour cameras, switch to a BAYER pixel format to use YUV422.
When viewing the image in Pixelink Capture, the two frames will be displayed side by side; With the low gain image on the left, and the high gain image on the right:
Any images saved when Interleaved HDR is enabled, will also save in this format, as shown in the example below:
For API Documentation on these HDR modes, see: Gain HDR