rxmd
This was not supposed to start a brand war, however, the Canon 50/1.4 is no better than the corresponding Nikkor. I tested the Nikkor against the Zeiss 50/1.4 ZF and there was no contest, I tested it against the Makro Planar 50/2 ZF and there was even less contest, and I have tested the Makro Planar against the Planar ZM, and honestly speaking, it looks to me like the ZM version is slightly ahead, This relates to overall image quality, not only to sharpness, but my Makro Planar is as sharp full open, as the Nikkor at f4.0. It may be subjective to a point, but not totally subjective - maybe you can try to shoot your Canon lens on film and compare it to a first rate RF lens on the same type of film. I tried Nikkor against Zeiss both on digital and film, and there was never any contest. This is in part due to the different construction requirement of a normal lens in case of the absence of a mirror box - it is widely known for example, that even the Planars put on the Rolleiflex cameras in the 60' come out ahead of the same (nominally) Planars for the Hasselblad of a much later production.
As far as the 24 Canon lens, I can bet a good bottle of wine, that it cannot even kiss the legs of the current Leica Elmarit 24, not to speak about the Biogon 25 - they are both f2.8 lenses, so obviously they have an "unfair" advantage, but even a bigger advantage lies in their non retrofocus construction. If you go to fredmiranda alternative lens users forum, you will find that everybody raves about the C/Y Distagon 21 - well, I bet another bottle, that the 21/4.5 C Biogon wipes the floor with that lens... So there you are, you have 2 bottles of wine to win ! This might actually prompt you to shoot more splendid photographs ! 🙂