New processing for SOHO’s LASCO and EIT

New image processing has been implemented for LASCO C2 and C3 coronagraph data. The default processed images from NASA with applied center rotation are now accessible from the respective [ALT] links.

The new processing includes stronger star field filtering combined with a modified approach for subtracting the background for C2 from a daily regenerated mean background from the last 96 hours. This approach produces some artifacts, such as darker regions near the occulter disk but it helps with the contrast of some fainter CMEs.

If the latest image is not fully retrieved from the spacecraft, the previous available one is used to fill the gaps in the data until the new image data are available.

The diff processing for C2 and C3 was also improved resulting in better data/noise ratio and all null pixels in the resulting images are mapped to rgb(128, 128, 128).

Although EIT images cannot compete with the resolution and cadence of the SDO AIA ones, their processing was also updated in order to improve their dynamic range and details.