Z-Image Turbo Upscaler + Detailer ComfyUI Workflow: Complete Guide
Published: 2026-05-13
Author: Z-Image Tech Team
Tags: Z-Image Turbo, ComfyUI, Upscaler, Detailer, Workflow, Image Upscaling
Overview
Z-Image Turbo is renowned for its blazing-fast 8-step image generation, but its native output resolution is typically capped at 1024×1024. When you need higher-resolution, more detailed images, the Upscaler + Detailer two-stage workflow is the optimal solution.
This guide walks you through building a complete ComfyUI workflow that requires only 4 model files to achieve a full pipeline from standard output to 4K high-definition images.
Workflow Architecture
The complete Upscaler + Detailer workflow consists of three stages:
Stage 1: Base Generation (Text-to-Image)
Generate the base image using Z-Image Turbo:
- Model:
z_image_turbo.safetensors - Sampler: Euler
- Steps: 8-12
- CFG: 1.5-2.0
- Output Resolution: 1024×1024
Stage 2: Super-Resolution Upscaling (Upscaler)
Scale up the base image by 2-4x:
- Recommended Upscale Models:
4x-UltraSharp.pth— Best general-purpose upscaler4xFaceUpDAT.pth— Face-specialized, accurate skin toneRealESRGAN-x4plus.pth— Classic choice, fast processing
- Scale Factor: 2x (recommended) or 4x
- Output Resolution: 2048×2048 or 4096×4096
Stage 3: Detail Refinement (Detailer)
Use Z-Image Turbo to enhance details on the upscaled image:
- Model:
z_image_turbo.safetensors(same as Stage 1) - Denoise: 0.15-0.35 (low preserves structure, high adds detail)
- Steps: 8-12
- CFG: 1.5-2.0
- Key: Provide detailed refinement prompts
ComfyUI Node Configuration
Core Node List
1. CheckpointLoaderSimple — Load Z-Image Turbo model
2. CLIPTextEncode (Positive) — Positive prompt
3. CLIPTextEncode (Negative) — Negative prompt
4. EmptyLatentImage — Initial latent (Stage 1)
5. KSampler — Base generation sampling
6. VAEDecode — Decode to pixels
7. ImageUpscaleWithModel — Super-resolution upscaling
8. UpscaleModelLoader — Load upscale model
9. VAEEncode — Re-encode to latent (Detailer stage)
10. KSampler — Detail refinement sampling
11. VAEDecode — Final decode
12. SaveImage — Output
Node Connection Flow
CheckpointLoaderSimple → CLIPTextEncode(+/-)
↓
KSampler(Stage 1)
↓
VAEDecode
↓
+-------+-------+
| |
SaveImage(original) ImageUpscaleWithModel
↓
VAEEncode
↓
KSampler(Stage 2)
↓
VAEDecode
↓
SaveImage(final)
Detailed Parameter Tuning
Upscaling Stage Parameters
| Parameter | Recommended | Description |
|---|---|---|
| Upscale Model | 4x-UltraSharp | Best for general scenarios |
| Face-Specific | 4xFaceUpDAT | Portrait priority |
| Scale Factor | 2x | Balance quality and speed |
| Tile Mode | Off | Z-Image Turbo natively supports large images |
Detailer Stage Parameters
| Parameter | Recommended | Description |
|---|---|---|
| Denoise | 0.25 | Sweet spot, balances structure and detail |
| Steps | 8-12 | Z-Image Turbo optimal range |
| CFG | 1.8 | Medium guidance strength |
| Detail Prompt | See below | Enhance specific areas |
Detail Refinement Prompt Templates
Portrait Refinement:
extreme detail, sharp eyes, skin texture, realistic pores, fine hair strands,
professional photography, 8K UHD, highly detailed
Product Refinement:
product photography, sharp focus, studio lighting, clean background,
high resolution, professional product shot, reflective surfaces,
fine texture details
Landscape Refinement:
landscape photography, ultra detailed, atmospheric perspective,
sharp focus, professional camera, 8K, HDR, fine detail
Practical Workflow Templates
Template 1: Quick Portrait Refinement
Stage 1: Generate
- Resolution: 1024×1024
- Steps: 8
- CFG: 1.5
Upscale:
- Model: 4xFaceUpDAT
- Factor: 2x
Stage 2: Refine
- Denoise: 0.20
- Steps: 10
- Prompt: extreme facial detail, sharp eyes, skin texture, professional portrait
Template 2: Product Photography Upscale
Stage 1: Generate
- Resolution: 1024×1024
- Steps: 10
- CFG: 2.0
Upscale:
- Model: 4x-UltraSharp
- Factor: 4x
Stage 2: Refine
- Denoise: 0.30
- Steps: 12
- Prompt: product photography, studio lighting, sharp focus, 8K
Template 3: ControlNet-Assisted Refinement
For scenarios requiring structural consistency, add a ControlNet Tile node in the Detailer stage:
Upscaled Image → ControlNet Tile Preprocessor → ControlNet Tile Model
↓
KSampler(Stage 2)
Advantages:
- Prevents structural drift during the Detailer stage
- Preserves original composition
- Ideal for architecture, products, and precision-demanding scenes
Common Issues and Solutions
Issue 1: Blurry After Upscaling
Cause: Mismatched upscale model or denoise value too low.
Solution:
- Try
4x-UltraSharpinstead ofRealESRGAN - Increase denoise from 0.15 to 0.25
- Add
sharp, crisp, detailedto detail prompts
Issue 2: Over-Modification in Detailer Stage
Cause: Denoise value too high, model "over-creates."
Solution:
- Lower denoise to 0.15-0.20
- Use ControlNet Tile for constraint
- Keep positive prompts concise
Issue 3: Out of Memory
Cause: 4K output requires significant VRAM.
Solution:
- Use GGUF Q4 quantized models
- Process in tiles (tile size: 512, overlap: 64)
- Two-step upscaling: 2x then 2x, rather than 4x at once
Performance Benchmarks
| Configuration | Generation | Upscaling | Refinement | Total | VRAM |
|---|---|---|---|---|---|
| RTX 3090, 2x | ~4s | ~3s | ~5s | ~12s | ~8GB |
| RTX 3090, 4x | ~4s | ~6s | ~8s | ~18s | ~12GB |
| M4 Mac, 2x | ~8s | ~6s | ~10s | ~24s | ~16GB |
Advanced Techniques
1. Multi-Stage Progressive Upscaling
For ultimate quality, use a three-stage workflow:
1024px → (2x) → 2048px → (refine) → 2048px → (2x) → 4096px → (refine) → 4096px
2. Face Detailer Dedicated Node
The ComfyUI community's Impact Pack provides a FaceDetailer node that automatically detects faces and performs local refinement:
Upscaled Image → FaceDetailer → Output
Parameters:
- Detection threshold: 0.5
- Detailer denoise: 0.3
- Face mesh: Default
3. Batch Processing
Use ComfyUI's Batch node with folder input for batch upscaling and refinement:
FolderInput → ImageUpscaleWithModel → VAEEncode → KSampler → VAEDecode → SaveImage
Summary
The Z-Image Turbo Upscaler + Detailer workflow is a powerful tool for improving image quality and resolution:
- Only 4 model files needed, simple setup
- Fully automated end-to-end, from generation to output
- 8K output, meeting professional-grade requirements
- Multi-scenario adaptation, with templates for portraits, products, and landscapes
Master this workflow and your Z-Image Turbo generation capabilities will reach a whole new level.