Over the last 6 months or so I have been watching the development of a potential flaw in Sony cameras when it comes to astrophotography and long period low-light exposure.
PetaPixel a well known photography site has now made the call to publish the article listed here PetaPixel StarEater . If you have updated your firmware lately you need to be aware of this issue.
This incorporates a model by model summation of the Sony cameras.
For those of you who follow the astrophotography forum at DPreview you are probably aware of the issue, and like Ian, I wont steer anyone towards a Sony ( for general astrophotography only ) until we have a fix from Sony on this subject. This could be a long time coming or it could be a simple as a menu switch to turn the “new improved algorithm ” on and off as required.
I will post any changes to this situation a things progress.
A comparison of an unaffected exposure with a “Star Eater” exposure at 100% crop from PetaPixel