Print Sigmas

A scheduler node in ComfyUI hands you a SIGMAS list - the actual sequence of noise levels the sampler will step through, from mostly-noise down to nearly-none. Most of the time you never look at that list directly; you just trust whatever the scheduler produced. This node is the one that lets you actually see it: wire your SIGMAS output through here, and it prints the raw values so you can check the schedule is doing what you think it's doing, before you spend time blaming the sampler for something the scheduler caused.

Why this is worth having in your toolbox

This matters more than it sounds like on a quick read, especially with the current wave of custom sampling tools. A well-documented gotcha with third-party scheduler packs (RES4LYF is the common example) is that certain schedulers apply their own internal sigma shift and simply ignore the shift value you set elsewhere in your workflow - so you dial in a shift, see zero visible effect, and reasonably conclude the setting is broken. It isn't; the scheduler quietly overrode you. The only way to actually catch that is to look at the sigma values themselves and notice they don't match what you expected from the shift you configured - which is exactly what this node is for. If you're troubleshooting a sampler that "isn't listening" to a schedule-related setting, this is the first node to reach for, not the last.

More generally, it's useful any time you're building or debugging a custom sampling setup and want ground truth on how noise is actually being removed step by step, rather than inferring it from the final image.

Inputs and outputs

• sigmas (SIGMAS) - the noise schedule you want to inspect, typically coming straight from a scheduler node like Basic Scheduler, Karras Scheduler, or a third-party one.

The output is also SIGMAS, and it's a passthrough - the exact same values you fed in, unmodified. That's deliberate: it means you can drop this node into the middle of an existing sampling chain purely to inspect the values passing through, without breaking anything downstream. It's also marked as an output node in ComfyUI, meaning it can execute and print even if nothing is connected after it.

Installing it

ComfyUI Manager: search "ComfyUI-Image-Filters," install, restart. Or:

cd ComfyUI/custom_nodes
git clone https://github.com/spacepxl/ComfyUI-Image-Filters

pip install -r requirements.txt (or install.bat on Windows), restart. Nothing to download - it's a debug utility, not a model.

The pack's general OpenCV dependency issue applies at install time even for a node this simple, since it's part of the same repo: if another node pack put a conflicting opencv/cv2 build on your system, the whole pack can fail to import. import_error_install.bat cleans that up by reinstalling the single correct variant.

Common issues

The values print to the console/log, not anywhere visible in the ComfyUI UI itself - if you're expecting to see numbers appear on the node or in a panel, check your terminal output instead (see Show Sigmas, this pack's other sigma-inspection node, if you specifically want an on-canvas display rather than a console print - the two aren't functionally documented as identical, so try both if one doesn't show you what you expect). Beyond that, there's not much that goes wrong here - it's a passthrough, so wiring it into an existing chain shouldn't change your generation output at all. If it does change something, that's worth investigating as a bug, not an expected side effect of inspecting the schedule.