The 127/3.8 is a light lens (no pun intended). The 110 is 2.8 so it should have much bigger glass inside. It also has more lens elements than the 127/3.8.
The funny thing is that IIRC the 110/2.8 was the lightest RZ lens? Or at least the smallest then.
Yes, the 110/2.8 is the smallest and lightest lens for the RZ and the 127 for the RB. They may be the fastest ones but if you think about it, in 35mm cameras the lightest and smallest lenses are the 50s, even though they are all f/1.whatever.
I will have to look at my RB67 lenses and get the details. I believe they are the older lenses. I recall seeing some Portra Images on a Facebook RB67 group and the lens images are super clear.
So I am sure the later lenses are better built. I might have to shoot with them this week and run a roll thru just to see.
I better start doing some stretching exercises so I can pick up the camera without slipping a disk [emoji12]