Negative Cond Placeholder

FLUX.1 doesn't use negative conditioning. It runs at a guidance setup where there's no classifier-free guidance pass for a negative prompt to act through, so the negative slot is dead weight - but Impact Pack's samplers and detailers still have a negative input that wants something plugged in. Negative Cond Placeholder is that something. It's a node whose entire purpose is to hand those inputs a valid empty negative so the graph runs, without you encoding a pointless negative prompt through CLIP.

The README says it directly: "Models like FLUX.1 do not use Negative Conditioning. This is a placeholder node for them. You can use FLUX.1 by replacing the Negative Conditioning used in Impact KSampler, KSampler (Inspire), and Detailer with this node."

How it works

There's genuinely nothing to it - and that's correct. It outputs a placeholder CONDITIONING that satisfies the type requirement of a negative input without carrying any actual negative guidance. You wire it into the negative slot of an Impact KSampler, a detailer, or a detailer pipe when you're running FLUX (or any CFG-1 distilled model that ignores negatives), and the node stack is happy. No wasted CLIP encode, no fake negative prompt, no CFG confusion.

The inputs and outputs

This is about as minimal as a node gets: no inputs at all, and a single output, CONDITIONING. You drop it on the canvas and run a wire from its output to wherever a negative conditioning is required. That's the complete operation.

How to install it

ComfyUI Manager: search ComfyUI Impact Pack, install, restart. Manual: cd ComfyUI/custom_nodes && git clone https://github.com/ltdrdata/ComfyUI-Impact-Pack, install requirements into ComfyUI's Python (pip install -r requirements.txt, or ..\..\..\python_embeded\python.exe -m pip install -r requirements.txt on Windows portable), then restart. Auto-install was removed at v7.6, so the requirements step is manual. A small SAM model downloads to ComfyUI/models/sams on first run - part of the pack, not this node.

Common issues

You're using it on a model that does want a negative. Don't. On SD1.5, SDXL, and anything running real CFG, a negative prompt does actual work - replacing it with this placeholder throws away your negative guidance. This node is specifically for FLUX-style models that ignore the negative anyway. Use a proper CLIP-encoded negative everywhere else.

FLUX still runs slow or looks off. This node only handles the negative-slot plumbing; it doesn't tune FLUX. Guidance, steps, and scheduler are separate concerns. If output quality is the problem, look there, not here.

Version won't show the node. FLUX support in Impact KSampler and the detailers arrived in v6.0. If this node or FLUX-in-detailer behavior is missing, you're on an old pack - update through ComfyUI Manager. As always with this pack, keep it and ComfyUI core roughly in step.