Sigmas Add

This is one of the little sigma-surgery nodes in RES4LYF, and it does exactly what the name says: it takes a sigma schedule and adds a fixed number to every value in it. Not glamorous. But if you've ever wanted to shove the whole noise curve up or down without switching schedulers, this is the blunt instrument for it.

Quick refresher, because "sigmas" trips people up. A sampler doesn't remove noise in one go - it walks down a ladder of noise levels, and that ladder is the sigma schedule. Your scheduler node (beta, simple, beta57, whatever) generates it. Higher sigmas early, near-zero at the end. RES4LYF's whole reason to exist is that on flow-matching models - Flux, Chroma, HiDream, Wan, SD3.5 - the shape of that curve matters a lot, and the pack ships a pile of nodes for reshaping it vs. time. Sigmas Add is the simplest of them.

How it works

You feed it a SIGMAS list from a scheduler node. It adds your addend to every element and hands back a new SIGMAS. That's the entire mechanism - a constant offset applied across the board. A positive addend raises every noise level (more denoising work at each step, generally a rougher, more "reconstructed" feel); a negative one lowers them. Because it touches the whole schedule uniformly, it's a coarse move, not a precision one.

The inputs and outputs that matter

There are only two, and one is the star:

• sigmas (SIGMAS) - the schedule you're modifying. Comes from any scheduler node.
• addend (FLOAT, default 1, range -1000 to 1000) - the number added to every sigma. This is the only knob. In practice you're working in small fractions, not whole units - the default of 1 is a big shove on most schedules, so start smaller and watch what it does to the last few steps.

Out comes a single SIGMAS. Wire it into the sigmas input on a ClownsharKSampler (or any custom sampler that takes an external schedule). Remember: plugging sigmas into the sampler overrides the scheduler and step count picked inside the sampler node, so this node's output is now driving the show.

How to install it

Two ways, same as the rest of the pack. ComfyUI Manager: open Manager, search RES4LYF, install, restart. Manual: cd ComfyUI/custom_nodes && git clone https://github.com/ClownsharkBatwing/RES4LYF/, then if you're in a venv activate it and run pip install -r requirements.txt (portable ComfyUI: swap pip for your embedded python's pip). Restart ComfyUI and hard-refresh the browser with F5, not just "r".

If you want the pack's nested sampler menu, also install rgthree-comfy and make sure "Auto Nest Subdirectories" is checked in rgthree's settings - the author recommends having rgthree regardless.

Common issues

The honest one: this node does nothing on its own. If you drop it in and see no change, check that its output is actually wired into the sampler's sigmas input and not left dangling - a schedule you build but never connect gets ignored, and the sampler falls back to its internal scheduler.

The other thing to watch is going too far. The last sigma in a schedule is usually at or near zero; add a chunk to it and you can leave residual noise in the final image (grain, a slightly unfinished look) because the sampler never gets down to a clean floor. If your output suddenly looks noisy, your addend is too high - that's the node working, not breaking. This is deep-end sigma tinkering, so change one value at a time and keep a fixed seed while you do it, or you'll never know which knob moved the result.