Any Examples of Upswept vs S-curve in prints?

Hey,


Can anyone share examples of upswept curves on film enlarged in the dark room and s-shaped curves as well.

I'd like to see some side by side.

Not easy to tell because the paper imparts its own pronounced 's' shape on the overall tone reproduction cycle that can overwhelm whatever is going on with the negative tonal separation. In general, however, a negative exposed on the toe (where the shape is upswept) will have not so good shadow separation compared to the same scene exposed on the straight line. But if you are talking about the resulting prints on photographic paper, the difference may not be as great as you would expect.

Tech pan was often used for an upswept curve when making negs frrom reflective material; plus x was the next best thing per a mid 80's Kodak 'Copying and Duplicating' manual I use.

Upswept was used here to prevent mid tone compression.

So no one on this film forum here has printed film negatives that have had a upswept curve to them or an S-shaped curve?