Flux Empty Latent Image MXD

There's an entire genre of r/comfyui thread that starts "why does my Flux output look soft / warped / inconsistent?" and the answer is usually the same: you generated at a resolution Flux wasn't trained at. Flux.1 Dev and Schnell were trained on specific resolution buckets, and staying on them is free quality. Flux Empty Latent Image MXD makes that a one-click decision - it's the core Empty Latent Image with Flux's training resolutions in a dropdown, a vertical toggle, and a batch size.

What it is

A resolution-preset latent generator for the Flux family. Pick a resolution, decide orientation, get a LATENT. It's the flagship of the MaxedOut pack's "resolution presets" lineup - the README calls it out by name alongside the SDXL and Z-Image variants.

The dropdown carries 18 entries across three tiers, all Flux bucket shapes:

• High: Square 1408², 4:3 1664x1216, 3:2 1728x1152, 16:9 1920x1088, 21:9 2176x960
• Standard: the 1024² class - 1024², 1152x896, 1216x832, 1344x768, 1536x640
• Low: 320² class for quick preview passes (320² down to 576x256)

The "Standard" row is where most real work happens; the "High" row is for big-output runs on capable cards; "Low" is genuinely useful for fast previews at low cost - a trick most people only discover after their first slow 2176-wide draft.

How it works

Flux.1 uses the SD3-style latent: 16 channels with 8x spatial compression. The node allocates a zeros tensor at [batch, 16, h//8, w//8] on ComfyUI's intermediate device and returns it as {"samples": ...} - the standard empty latent contract that KSampler expects. The vertical toggle swaps width and height before the division. Nothing is encoded; it's pure initialization space.

Inputs and outputs

• resolution - the dropdown, default Square (1:1) 1024x1024 (the 1MP starting point).
• vertical - swap to portrait.
• batch_size - 1 to 4096; 1 unless you're batch-generating.
• Output: LATENT → sampler's latent input.

Install

cd ComfyUI/custom_nodes
git clone https://github.com/Maxed-Out-99/ComfyUI-MaxedOut.git

Restart, or ComfyUI Manager → search "Maxed Out" → install. No model files, no extra deps.

Troubleshooting

• "… is a header or invalid option" - you selected one of the - High Resolutions - section headers. They're in the dropdown as labels; pick a real preset.
• Latent channel mismatch - this makes 16-channel latents. If you're sampling Flux 2 (which wants 128 channels / 16x compression), use the pack's Flux 2 Empty Latent node instead. Wrong latent family, wrong results.
• OOM at High tier - Flux at 2176x960 is heavy. Drop to Standard, or keep High for cards with serious VRAM.

For "I just want a correct Flux-sized latent without typing", it's the exact right tool - and it pairs cleanly with the pack's Flux Resolution Selector if you want the resolution choice centralized.