Which slide film did you choose; Velvia, Astia, HP5 in DR5?
Push, pull, normal?
What did you peg exposure to?
For color negative films, in the 'old days', automatic printers assumed each image averaged to some shade close to gray; modern printing algorithms are much more sophisticated. There are prints known as 'first prints' that result from the algorithm; most good labs will reprint 'first prints' that are off in color or density.