not sure the EM1 was intended to be a superior product line than the EM5. It was billed as the "successor" to the EM5. so maybe the EM5 ii is the successor of EM1
'Superior product line'? Doesn't make sense. The E-M1 model is currently the Olympus top of the line body, in the OM-D product line, intended as the pro-grade replacement for their last DSLR, the E-5.
In the OM-D line, the E-M5 was the first out, followed by the E-M1, and then the E-M10. The E-M10 included a couple of new features beyond the E-M1, with the sensor package of the E-M5. The E-M5 II follows the E-M10 in time, includes some of the new features that surfaced first in the E-M10, etc.
The E-M1 remains the top of the line. It is often the case that the top of the line camera body follows other models when it comes to features as the top of the line model development cycles more slowly than the mid-line models.
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