scheduler_sigmas2Graph

A sigma schedule is just a list of numbers - how much noise gets removed at each step - and it's genuinely hard to reason about a list of numbers by eye. This node turns any SIGMAS input into an actual line graph, so you can see the curve shape instead of squinting at a column of floats. It's a debug tool more than a creative one, and it earns its keep specifically when you're using this pack's other scheduler-editing nodes: scheduler_manual_sigmas (write your own formula), scheduler_interactive_sigmas (drag points on a curve), or Scheduler_MixScheduler (blend two schedules at a split point) all produce a SIGMAS output that's much easier to sanity-check visually than to trust blind.

The inputs and outputs that matter

• sigmas (required, SIGMAS) - the schedule you want plotted. Works with output from any scheduler node, stock or custom.
• color (default blue, 15 choices) - line color. Purely cosmetic, but useful if you're comparing multiple schedules side by side and want to tell them apart at a glance.
• print_as_list (default false) - when on, also prints the raw sigma values to the console/log, for when you want the exact numbers rather than just the shape.
• scale (default linear, or log) - the y-axis scale. Sigma values span a wide range from the first step to the last, and a log scale often makes the tail end of the curve (the low-noise, detail-refining steps) actually visible instead of flattened against the x-axis by the much larger early values.
• Output: IMAGE - the rendered graph, which you can view directly in ComfyUI's preview or save like any other image output.

How to install it

Search ComfyUI-Apt_Preset in ComfyUI Manager, or clone it manually:

cd ComfyUI/custom_nodes
git clone https://github.com/cardenluo/ComfyUI-Apt_Preset.git

install.bat handles Windows dependencies; on Linux or Mac, open it, read the pip installs, and run them yourself, or let ComfyUI Manager fill in anything missing on first load. No model files needed - this is a pure visualization node.

Common issues & troubleshooting

The curve looks flat except right at the end. That's almost always a linear-scale artifact, not a real property of your schedule - sigma values typically drop off steeply, so early steps dwarf later ones on a linear axis and compress all the interesting detail into a sliver near the x-axis. Switch scale to log and the shape usually becomes readable.

Comparing two schedules and can't tell them apart. Set a different color on each scheduler_sigmas2Graph node and view both outputs side by side, rather than trying to overlay them from memory between two separate previews.

Need the exact numbers, not just the shape. Turn on print_as_list - the graph is for shape, the console output is for precision. Useful when you've hand-tuned a schedule with scheduler_interactive_sigmas and want to copy the resulting values somewhere else, or verify a scheduler_manual_sigmas formula actually produced what you intended.

This node feels like overkill for a quick check. It is, for a quick check - but the moment you're doing anything beyond "pick a name from the dropdown" (mixing schedulers, hand-editing a curve, writing a custom formula), it stops being optional. Trusting an untuned custom schedule without looking at it first is how you end up debugging a bad render by trial and error instead of by looking at the one thing that actually explains it.