Prompt TipsFeb 11, 20269 min

10 tips for writing image prompts that actually control the output

A practical, developer-friendly guide to writing image prompts with clear constraints, fewer surprises, and faster iteration.

10 tips for writing image prompts that actually control the output

Most "bad" image prompts aren't bad because they lack imagination. They're bad because they're underspecified in the places the model needs structure, and overspecified in the places the model can't reliably bind details.

That sounds contradictory, but it's exactly what shows up when you look at prompting under real conditions. In XR object detection, for example, pragmatically ambiguous prompts ("I'm thirsty…") can tank performance, while overly detailed attribute salads can also degrade results for some models-because you've created competing constraints that are hard to satisfy consistently [1]. Different task, same failure pattern: the model is guessing what you meant.

Here's the mental shift that unlocked image prompting for me: an image prompt is not prose. It's a spec. And like any spec, it works best when you define (1) the goal, (2) the context, and (3) the acceptance criteria-an "output contract" that reduces ambiguity and keeps iteration cheap [2].

Below are 10 tips I use to write prompts that behave more like controllable interfaces than lottery tickets.


Tip 1: Start with a single "anchor" subject (and make it unmissable)

If you want control, you need a center of gravity. Put the primary subject first, and phrase it as a noun phrase the model can latch onto (not a vibe).

Instead of "cinematic portrait of innovation," write something like "a waist-up studio portrait of a software engineer holding a circuit board."

This mirrors what prompt-robustness studies show: once the prompt crosses a threshold of semantic clarity, performance stabilizes; before that, you get chaos [1]. Your anchor is that clarity threshold.


Tip 2: Convert intent into visible attributes, not pragmatic hints

Humans love indirect requests. Models hate them.

"I'm thirsty-hand me something to drink from" makes sense to a person. But under pragmatic ambiguity, systems can fail hard because the prompt doesn't name visual attributes that can be grounded [1]. Image generators have the same issue: they don't reliably infer the object you meant when you imply it.

So: say the object. Then give 2-4 intrinsic attributes that disambiguate it (material, color, shape, condition). If you can't describe it, you're not ready to prompt it.


Tip 3: Add composition like a photographer, not a poet

Most prompts describe what is in the image but forget to describe the shot. Composition is the difference between "a dog on a beach" and a usable hero image.

I like to treat composition as part of the output contract: framing, angle, distance, and what must be inside the crop. This is also how you reduce downstream surprises, because composition constraints shrink the space of plausible generations (same principle as prompt "output contracts") [2].


Tip 4: Specify lighting because it controls realism more than "quality" ever will

"High quality" is almost never an instruction. Lighting is.

If you want photoreal, describe a plausible lighting setup: "soft key light from camera-left," "hard noon sun," "overcast diffuse skylight," "rim light," "soft shadows," and so on. This forces the model to commit to a coherent physical story instead of spraying generic HDR gloss everywhere.

This is a classic "goal + constraints" move: you're defining what "good" means in terms the model can render [2].


Tip 5: Use style as a constraint set, not a vibe word

Style words like "cinematic" or "epic" are weak unless you pin them down with references the model can operationalize: medium ("35mm film still"), era ("late 90s street photography"), palette ("muted teal/orange"), rendering type ("flat vector icon set"), or production context ("ecommerce packshot on seamless white").

In design tooling research, one recurring theme is that alignment improves when intent is represented as structured choices (purpose/content/style) instead of one big mushy prompt blob [3]. You don't need a graph UI to steal the idea: break "style" into components.


Tip 6: Don't over-specify: pick the minimum attributes that disambiguate

Here's the trap: you think more detail equals more control. Sometimes it does. Sometimes it creates conflicts.

In OSOD experiments, overdetailed prompts degraded performance for a strong model, likely because multiple objects partially match subsets of the description and the model can't prioritize attributes cleanly [1]. Text-to-image models have a similar binding problem: if you stack too many descriptors, you increase the chance that one will be ignored, misapplied, or "satisfied" in the wrong place.

My rule is boring but effective: add attributes until the image stops drifting, then stop.


Tip 7: Use negative constraints sparingly, but surgically

Negative prompting isn't about listing every failure you've ever seen. It's about preventing the two or three failure modes that are most likely for this prompt.

This is straight out of general prompt design: explicit constraints are a form of risk management, and they work best when they're specific and testable ("no watermark," "no extra fingers," "no text") [2].

If you write a huge "no … no … no …" paragraph, you'll eventually contradict your own prompt or block something you needed.


Tip 8: Declare your output contract: aspect ratio, background, text rules

If you're generating product images, thumbnails, or ads, the prompt needs hard layout rules. This is where developers and PMs can win, because you're already used to thinking in specs.

An output contract is just: "format + acceptance criteria." Prompts that specify structure and constraints improve consistency and usability, especially for automation [2]. For images, that means things like: "1:1 square," "clean background," "subject centered," "leave negative space on the right," "only these exact words."

If the model struggles with text rendering, don't sneak typography in as an afterthought. Make it a first-class requirement, or plan to add text in post.


Tip 9: Iterate like an engineer: change one variable at a time

The fastest way to get "lucky" is to be systematic.

Treat each prompt revision as a controlled experiment: change lighting only, or camera only, or wardrobe only. That gives you causal feedback instead of a confusing before/after where everything changed.

This is the same logic used in evaluation-oriented prompt workflows: measure robustness under perturbations; don't randomly thrash [2]. You can do that informally without building a whole harness.


Tip 10: When you need consistency, use reference images-and tell the model what to preserve

If you're trying to keep a character consistent across scenes, or keep a product identity stable across marketing images, you're fighting one of the hardest problems in image generation: identity and attribute binding.

In practice, reference images help because they give the model something concrete to condition on. But you still need to state what is invariant: facial features, proportions, logo placement, color, shape, and what must not change. That's you writing the invariants of the system.

It also matches what we see in prompt enhancement pipelines: when ambiguity is resolved into explicit, intrinsic attributes (what the object is, not where it is), systems become far more robust [1].


Practical examples (copy/paste prompts)

These are intentionally structured. They're not "beautiful." They're controllable.

Example 1: Product hero image (clean, consistent, ad-ready)

Subject: a matte black stainless steel water bottle with a silver neck ring and a black carry-loop lid; no logo, no text.
Scene: placed on a light gray concrete countertop in a modern kitchen; background softly blurred.
Lighting: natural window light from camera-left; soft shadows; realistic reflections; no glow.
Camera/composition: 3/4 angle product shot, 50mm look, bottle centered; leave 30% negative space on the right for copy; 16:9.
Style: photoreal product lifestyle photography; true-to-life color.
Hard exclusions: no extra objects, no additional bottles, no labels, no watermark, no text.

This kind of "stack of constraints" prompt template is very common in community practice because it makes drift obvious and iteration easy [4].

Example 2: Portrait with controlled look (less "vibe," more spec)

A waist-up studio portrait of a 30-year-old woman wearing a charcoal blazer and white t-shirt.
Expression: neutral and confident; direct eye contact.
Lighting: soft key light from camera-right, subtle rim light, natural skin texture, no smoothing.
Camera: 85mm portrait look, shallow depth of field, eyes sharp, background plain dark gray.
Output: vertical 1080x1350.
Negative constraints: no beauty retouching, no plastic skin, no distorted hands, no text, no watermark.

Example 3: If you only have a vague idea, use a "prompt expander" flow

A neat trick I've seen in practice is letting the system expand your short request into a structured prompt by extracting subject/composition/style fields before generation [5]. Even if you do it manually, that flow is the point: expand intent into constraints.


Closing thought

If you want better images, stop trying to sound inspiring and start trying to sound precise. Your job is to reduce the model's degrees of freedom in the places you care about, while leaving room for creativity everywhere else.

The next time an image comes out "almost right," resist the urge to rewrite everything. Pick one lever-subject attributes, composition, lighting, style, negatives, or output contract-and move only that. You'll get to "right" faster, and you'll understand why.


References

Documentation & Research

  1. User Prompting Strategies and Prompt Enhancement Methods for Open-Set Object Detection in XR Environments - arXiv (Junfeng Lin et al.) http://arxiv.org/abs/2601.23281v1
  2. Quantum Circuit Generation via test-time learning with large language models (Appendix: Prompting as an interface) - arXiv http://arxiv.org/abs/2602.03466v1
  3. ToMigo: Interpretable Design Concept Graphs for Aligning Generative AI with Creative Intent - arXiv http://arxiv.org/abs/2602.05825v1

Community Examples
4. Here is the prompt template to create great images with ChatGPT. Plus 10 prompts for specific image use cases - r/ChatGPTPromptGenius https://www.reddit.com/r/ChatGPTPromptGenius/comments/1qr79c6/here_is_the_prompt_template_to_create_great/
5. Image Generation Prompt Flow - r/PromptEngineering https://www.reddit.com/r/PromptEngineering/comments/1quvryb/image_generation_prompt_flow/

Ilia Ilinskii
Ilia Ilinskii

Founder of Rephrase-it. Building tools to help humans communicate with AI.

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