Let's revisit the title of this thread: Is FF sharper than APS-C? Not 'does FF take a better picture'. Yes, photographers care about 'better pictures' but that's not what's being asked here. Only sharpness. So in this case, taking pictures of a newspaper taped to a brick wall would be a far more appropriate test of the question than yours.
Again, such would be a valid complaint amongst photocopier repair techs.
But, ask any working photographer if it makes any sense to compare sharpness of two photographs of a real-world scene with dramatically different compositions, perspectives, depths of field, amounts of background blur, and all the rest, and they'll think you're either completely nuts or one of those crazy Internet measurebators who only takes pictures of newspapers taped to brick walls -- as if there's a difference.
In the context of a photography discussion, the question most reasonably should be considered to be, "Does 135 make sharper photographs
than APS-C?" Not, "Does 135 make sharper photocopies
Your test was not designed to answer the question, and therefore was flawed for the purpose at hand.
Physician, heal thyself.
I'll even concede the point that 135 and APS-C make comparable photocopy platforms.
Now, which system produces sharper photographs
Do you know the difference between a dependent variable and an independent variable, and how to tell when a dependent variable becomes a confounding variable? You used different lenses to take the different pictures.
Yes, I do know what a confounding variable is. And the fact that you led off with the different lenses demonstrates that you don't.
The hypothesis is that image sharpness is independent of sensor format, and that two formats with the same total pixels will produce images of the same sharpness. The experimental results falsified that hypothesis, even
-- nay, especially
though the choice of lenses is known to have biased the results in the opposite direction.
If your hypothesis is that John and Sue can both run as fast, and you then make Sue but not John carry a 25 pound sack of potatoes around the course, and if Sue still
manages to easily beat John, then you know that Sue is definitely the faster runner. You don't know how much faster a runner she really is, but you definitely know that she's a faster runner.
Had John won, you wouldn't know if he won because he's a faster runner or if it's because Sue was saddled with all those potatoes. Had they tied, you'd know that Sue was the faster runner, and that the difference in performance is equal to a sack of potatoes.
But neither scenario is what happened. What we found is that, even when we weigh down Sue with a sack of potatoes, she still crosses the finish line well before John.
And now you understand how confounding variables work, and why my choice of lenses makes the point more emphatic.
...unless, of course, it is your position that the 135 SF is actually sharper than the TS-E 24 II, but I rather doubt you'd be capable of such cluelessness.
Now, go through all of my other variables, and you'll find the same applies: they're tilting the scales, yes, but in favor of the smaller format. In addition to the sack of potatoes in the form of a "meh" lens compared with a legendary one, the larger format also
got weighed down with even more sacks of potatoes in the form of aperture (f/4 v
f/32), ISO (100 v
6,400), and post-processing (SOC v
Again, if the small format had turned out sharper or comparable, we would have a hard time making a conclusion. But that's not what happened. Even after we loaded down the larger format with all those sacks of potatoes, it still crossed the finish line first.
So, my test can't tell you how much
sharper the larger format is, but it most emphatically does tell you that the larger format actually is
(Even if they're equally lousy photocopiers.)