Here I post the link to the original scan:
The three strips were scanned simultaneously.
I later rescanned the strips using an iPad to backlit the negatives. Because I am not absolutely sure whether the light intensity was identical in all scans, I am not posting these.
The exposure at each frame is:
4: EI50 1/60 2.8
5: EI100 1/125 2.8
6: EI200 1/250 2.8
7: EI400 1/500 2.8
8: EI400 1/125 5.6
9: EI800 1/250 5.6
10: EI1600 1/500 5.6
11: EI1600 1/125 11
12: EI3200 1/250 11
Yes, I was slightly dumb that day and only realized I add duplicated some exposure latter.
I is also possible to note that exposure which are supposed to be equivalent are not perfectly identical. This probably has to do with calibration of shutter speeds. Frame 11 looks slightly thinner than 10. The same goes for frame 7 and 8.
Feel free to manipulate the file as you wish, and post your own results.
I have a 16 bits uncompressed file on request.