Working AI artists do not generate finished images in a single prompt. They use a multi-stage workflow that progressively refines the image through different techniques. Understanding this workflow is the difference between treating image generation as a slot machine (type prompt, hope for the best) and treating it as a craft with its own production pipeline.
The standard professional workflow has roughly five stages, though the exact structure varies by artist and use case.
Stage 1: Concept and reference gathering
Before any generation happens, the artist gathers references. This might mean sketching a rough composition on paper, collecting reference images from Pinterest or art books, writing out the key visual elements, or building a moodboard. The goal of this stage is to know what you are trying to make before you start trying to make it, so that when the model produces an output you can evaluate it against a clear target rather than against a vague 'does this look good.' Most amateur AI artists skip this stage entirely and start typing prompts blind. Most professional ones spend more time on this stage than on any other.
Stage 2: Coarse generation
Generate dozens of low-effort outputs to find a composition and approximate look that matches your target. At this stage you are looking for a base image that is roughly right, the composition is good, the lighting is in the right ballpark, the subject is plausible, even if many details are wrong. You are not trying to produce a finished image. You are trying to find a starting point. Working artists generate 20 to 50 candidates at this stage and pick the best one or two for the next stage. The key insight is that prompts at this stage should be relatively short and simple, long prompts at this stage just add constraints that make it harder to get to a good base.
Stage 3: Refinement via img2img and ControlNet
Once you have a good base image, you refine it. The two main techniques are img2img (also called image-to-image) and ControlNet. img2img takes your base image, adds some noise back into it, and runs the diffusion process again, but starting from your image instead of from pure noise. The 'denoising strength' parameter controls how much the new generation diverges from the original. At low denoising strength (0.2 to 0.4), the output looks almost identical to the input but with some details changed. At medium denoising strength (0.5 to 0.7), the structure is preserved but the rendering is mostly new. At high denoising strength (0.8+), the result is almost a fresh generation that only loosely respects the input.
ControlNet is the more surgical tool. Instead of preserving an image as-is, it extracts a specific structural feature from the input, a depth map, a pose skeleton, an edge map, a normal map, a segmentation mask, and uses that feature as a strict constraint on the new generation. Generating with a pose ControlNet means: 'make a new image that exactly matches this pose, but otherwise reinterpret everything.' Generating with a depth ControlNet means: 'preserve the 3D structure of the scene but change the styling and content.' ControlNet is the technique that turns image generation from 'roll the dice' into 'execute a specific creative intent.'
The key ControlNet types in 2026 are: OpenPose (for character poses), Depth (for 3D scene structure), Canny edges (for line work and outlines), Normal maps (for surface orientation), Segmentation (for separating regions of the image), and Intellectual Property (IP)-Adapter (for using a reference image to bias the style or identity). Working artists use 2-3 of these per image, layered together with different weights to produce specific effects. ComfyUI's node-based interface is the dominant tool for this kind of layered ControlNet work because each ControlNet becomes a separate node in the graph and you can see exactly how they combine.
Stage 4: Inpainting for targeted fixes
Inpainting is the technique of regenerating just a specific region of an image while keeping the rest unchanged. You draw a mask over the part you want to change, write a new prompt that describes what should be there, and the model regenerates only the masked region while preserving the surrounding pixels. This is the technique that fixes broken hands, bad faces, awkward poses, and unwanted background elements. It is the closest thing to 'undo this specific mistake' that the technology offers, and it is the difference between accepting whatever the model gave you and producing exactly what you wanted.
Inpainting is also where the quality difference between casual and professional users is most visible. A casual user might inpaint a single fix and call it done. A professional user might inpaint 15 different regions in sequence, first the hands, then the eyes, then the background lamp, then the texture of the wall, then a small composition adjustment in the corner. Each inpainting pass is small and targeted. The cumulative effect is an image that looks coherent because every region was fixed individually, by an artist with a clear sense of what each region needed to be.
Stage 5: Upscaling and finishing
The final stage is upscaling and color grading. Most generation happens at 1024x1024 or similar, which is too low for print or most professional uses. An upscaler model takes the 1024x1024 output and produces a 4096x4096 (or larger) version with added detail. The current best upscalers (Topaz Gigapixel AI, Magnific, Krea's upscaler) do more than just scale up, they add believable detail at the new scale, so the upscaled image looks like it was rendered at high resolution rather than blown up from low resolution.
After upscaling, professional workflows typically do a color grading pass in a traditional photo editor (Photoshop, Capture One, DaVinci Resolve for video) to refine the color palette, contrast, and overall mood. The image generation model produces the content; the color grading produces the finish. Many of the images you see in professional AI artist portfolios have been through both stages, even though only the generation step gets credited.