The first generation Grand Seiko SBGR001(Silver dial), SBGR023(Black dial)
The only difference between the SGBR001 (Silver dial) and SBGR023(Black dial) were the different dial colors.
All of the hands were finished with polish.
The second generation Grand Seiko SBGR051(Silver dial), SBGR053(Black dial)
The black dial on the SGBR053 was switched up by giving the hands and indexes a brushed finish.
The polished needle blacked out on the black dial depending on lighting conditions. This was improved on.
The beveling on the needle was a little bit deepened compare with the SGBR051 hands in order to make it easier to see against the black letter board.
However, there is no need to worry for those of you who own the SGBR001 and SBG023. The appearance hasn't changed, but the movement research on the 9S55 is progressing daily.
The hairspring setting has been adjusted, the gear accuracy has been improved on with an increased oscillating angle, and has been finely tuned. In the case of the OVH, the parts have been changed out, so that it can always be in best of Grand Seiko condition.
世界の腕時計 No.102 WORLD WRIST WATCH TIME SPEC No81