Zener diode characteristic curve

[Wytnucls]

I've been trying to visualize the characteristic curve of a 5.1V Zener diode on the oscilloscope, using the X-Y mode of a Rigol DS1052E.
I probed voltages across the Zener and a 1kOhm resistor in series, hooked up to a function generator producing a 100Hz sine wave at 20Vpp.
The best picture I could get, after some tweaking, is shown below.
Not entirely happy with the result.
I was wondering if anybody has tried this experiment and managed to get a smooth curve using a similar method.

[robrenz]

Why don't you set the FG to a slow ramp that one cycle is the same duration as your screen width and enough dc offset to just get the forward conduction portion. trigger off the FG voltage at the bottom of the ramp and capture one cycle.

[Wytnucls]

Tried that before without much success. Tried it again with same disappointing result.
If you have a screen grab and a set-up diagram, I may be able to replicate it. I must be doing something wrong.
Thanks for the suggestion.
Setting up the ramp and trigger is fine, but I can't get a proper curve for the zener.

[Wytnucls]

OK, I think I found my mistake. Not enough resolution on the vertical scale.
Here is the result (looks much better than the X-Y mode):
Thanks Robrenz!

[robrenz]

Looks good