Give ComfyUI a change budget.

“Make it photorealistic, improve the lighting, textures, reflections and vegetation, but keep everything the same.” There is an entire small tragedy inside that sentence.

The request appears in this week's FluxAI thread on enhancing architectural renders, and versions of it recur across ComfyUI discussions. The desired edits do not share a boundary. Lighting touches the whole frame. Reflections belong to surfaces. Planting occupies shapes. Texture can make a wall feel credible or quietly redraw its joints.

A downloaded graph cannot decide those permissions. The brief has to.

What is a change budget?

A change budget states how much reinterpretation each part of the image may receive. It turns a broad enhancement request into a sequence of bounded operations. The word “budget” matters because every generative pass spends some fidelity. Higher denoise, weaker controls and larger masks usually buy more invention by putting more source information at risk.

Begin with two columns. Protected facts include massing, openings, floor lines, roof profile, circulation, camera and material boundaries. Permitted changes include exposure, light character, surface microtexture, selected reflections, planting richness and removable entourage. If a requested change sits in both columns, split it into a local pass.

This extends the architectural preservation brief into graph design. The brief says what matters. The change budget decides how much generative freedom each operation receives.

Which edits can stay global?

Global passes are suitable for changes that genuinely belong to the full frame: modest exposure correction, broad color balance, restrained atmospheric cohesion and perhaps a light reduction in the synthetic cleanliness of a raw viewport. Even here, ask whether a deterministic grade can do the work. Curves and color transforms repeat. A diffusion pass improvises.

If generation is justified, start at low denoise with the original image-to-image source and a fixed seed. Keep a depth or edge condition when form matters. Our first-pass geometry lock explains why preservation should be established before adding style branches.

Do not put four local defects into the global prompt and hope the model practices restraint. “Add realistic plants and richer glass while improving the stone” gives every pixel an alibi. The output may be handsome. The comparison overlay will be less sociable.

When does an edit need a mask?

Use a mask when the requested change has an address. A reflection belongs to particular glazing. A rougher concrete finish belongs to a defined surface. New ground cover belongs inside a planting bed, not halfway through the accessible route.

The official ComfyUI inpainting guide documents the core pattern: load an image and mask, encode for inpainting, condition, sample and decode. It also describes growing the mask to help blending. Architectural work needs care at that step. Growing a mask into sky may be harmless. Growing it across a mullion gives the model permission to negotiate the mullion.

Save the mask beside the output and version it with the source. A perfect mask for yesterday's facade can be a precise tool for damaging today's revised one. Our global-pass, local-repair workflow keeps those revisions legible.

How should lighting be budgeted?

Lighting is broad in appearance and geometric in consequence. A warmer sky can be global. A new sun direction changes cast shadows, reveals depth and may contradict the modeled orientation. Interior glow can make glazing legible, but it can also invent rooms behind a facade.

Write the allowed move in physical terms. “Warm the late-afternoon grade while retaining the existing shadow direction” is reviewable. “Cinematic light” is a restaurant menu adjective wearing a hard hat.

Keep major shadows and contact points in the protected list. Compare roof overhangs, columns, trees and ground contact. If the generator adds a second sun, no prompt elegance makes the image coherent.

Why should materials and reflections be separate?

Material texture describes a surface. Reflection describes what that surface sees. Combining both in one pass invites the model to solve glass, metal, stone and their surroundings as a single decorative problem.

For opaque materials, preserve boundary lines and scale cues. A brick texture can look photographic while the bricks grow to the size of suitcases. For glazing, keep mullions outside the editable area where possible, and decide whether visible interiors are protected or permitted to change.

Run reflections after the broader light direction is accepted. The reflection repair workflow treats each glass zone as a local optical problem. That is slower than asking for “better reflections” once. It is faster than discovering that every window now reflects a different street.

How should vegetation be contained?

Planting is seductive camouflage. It breaks hard silhouettes, introduces varied detail and can hide a poor edge with admirable efficiency. It can also block doors, shrink windows and grow through canopies.

Give vegetation its own mask and its own acceptance check. The vegetation-pass method protects paths, kerbs, entrances, roof edges and principal views, then checks mature scale and cast shadow. Keep one source frame without planting enhancement in the review sheet.

Name growth habit, density and season only when those qualities belong to the design intent. Do not let a generic “lush” prompt turn a dry courtyard into a botanical confidence trick.

What should the graph record?

For each pass, save the source filename, mask, model, control model, prompt, negative prompt, seed, denoise, sampler, dimensions and output. Record the permission attached to that pass. “Glass reflection only” is more useful six weeks later than “final_v7_good.”

Preserve intermediate accepted frames. If vegetation fails after the material pass succeeds, return to the accepted material frame rather than rerunning the entire stack. The stage-checkpoint workflow makes that rollback ordinary.

Give every output a pass label and source hash. That pairing prevents an accepted local repair from becoming detached from the exact base it amended. It also makes a later review less theatrical: the reviewer can see which permission was granted, which pixels changed and which earlier checkpoint remains available.

Compare at full resolution with an overlay or difference view. Check protected facts after every pass, not only at the end. Small departures compound. A parapet softened in the global pass can disappear completely when a later texture pass decides it is sky.

Our take: the graph is the second document

Community threads often ask for a workflow file because the graph looks like the missing expertise. It is only the machinery. The first document is the change budget: what may move, what must hold and where generation is allowed to touch the image.

Write that page before loading a checkpoint. A good graph can execute a precise brief. It cannot rescue a vague one from itself.