You may find these helpful in your analysis Tech Camera Lens Specification
and Tech Camera Focal Length and Image Circle Visualizers
In general a Rodenstock lens:
- is heavier
- is larger
- is more expensive
- can be used modestly closer to wide open with good results
- can be used for a larger % of it's manufacturer-stated image circle (i.e. Rodenstock tends to give conservative IC specs)
- drops off in sharpness only shortly before the edge of the circle of illumination
- is less reliant on center filters (thought they may still benefit the final use)
In general a Schneider lens:
- is lighter
- is smaller
- is less expensive
- must be stopped down further than a Roddy for comparable results (though you may find good enough results near wide-open)
- can be used for a smaller % of it's manufacturer-stated image circle (i.e. Schneider tends to give liberal IC specs)
- drops off in sharpness moderately before the edge of the circle of illumination
- is more reliant on center filters
These are generalizations, and as such there are exceptions. There are also compatibility issues as noted by Paul above and in the links I put up top.
When a client comes to me there are a LOT of questions I want to ask them before I recommend a lens. Hopefully you're working with a dealer that has shot (practical real world images) with nearly every Schneider/Rodenstock lens available and can help you decide between the various pros/cons.
Note: most of the above analysis applies primarily to the normal and wide lenses. I have less experience with the 90+ mm focal lengths with the exception of 120mm lenses for Cultural Heritage Capture
applications. While we have some customers with long tech camera lenses the vast majority are using 70mm and shorter.