Sony has been quick to address the black sunspot issue and will release a firmware update for the Sony A7S II on 20th November

Sony has announced that will release a firmware update for the Sony A7S II that will fix the ‘black sunspot’ issue that has affected some of its cameras when shooting at 25fps.

The short announcement from Sony says:

Sony will release a firmware update for the α7S II camera on 20th November, 2015. It is designed to eliminate the occurrence of a black spot that may appear in frame when shooting in a specific set of high intensity light conditions.  The new firmware, version 1.10, will be available for download through Sony’s e-support site http://www.sony.eu/support/  on the product page for model “ILCE-7SM2”. 

We first spotted the issue when testing the A7S II  earlier this month and reported the problem here 

Following our findings, and those from other early A7S II users, Sony released a statement acknowledging the problem and saying that firmware fix would be on its way

 

Read our full review of the Sony A7S II