SAR reader Benjamin sent me this:
It seems the “star eater” bug is not fixed. Preliminary findings indicate, that the Sony algorithm now processes both green channels at once instead of seperately. This slightly reduces the overall filtering effect, but also seems to cause a green color cast on the smallest stars.
The details are discussed in these two threads:
https://www.dpreview.com/forums/thread/4168505
https://www.dpreview.com/forums/thread/4167521
Also John Leathwick confirmed on an article written for PetaPixel:
When Sony made their firmware announcement last week with promises of improved image quality for long exposures, many of us thought that this problem might at last have been addressed. However, slowly the evidence began to build that this was not the case – in my own testing of night-sky photos taken with the new firmware, the number of stars detected by the freely available image stacking software DeepSkyStacker is 70% lower in 5 second exposures than in 2.5 second exposures; visual comparison of these images shows the removal or dimming of many of the smaller stars once exposures are four seconds or longer.
Disappointing. Now let’s hope Sony will take quick action on this matter!