My First Oscilloscope - A question about calibration

[JoeNewberry]

The probes are 100MHz, 10x, 10MEG, 7.7pf capacitance.

The variable capacitor on the probe has allowed me to smooth out the curves, but I'm still getting sharp slopes instead of flat peaks. If I'm reading it correctly, it seems like the voltage rises where it should be a steady .5V across.

I've noticed that with no probes attached and the V/div setting at the lowest point, I can see a moderate sine wave. I assumed it was unavoidable background interference, since just getting my hand near the inputs is enough to generate a waveform. Could that small wave be getting added to my test signal and causing this rise?

I think I'll try testing on some actual circuits, on the off chance the calibration point is what's off. If I get the same results there, I may have to knuckle under and buy the service manual.