Prompting Image Models for AI Headshots That Keep Your Likeness

If you have tried turning a casual photo into a professional headshot with an image-editing model such as Gemini's image model (often called Nano Banana), you have probably seen the failure mode: the result looks polished, but it no longer quite looks like the person. The jaw is a little narrower, the skin is airbrushed, the hairline is fuller, and the person looks five years younger.

This post is a practical guide to avoiding that. It covers how to structure the prompt, which constraints do the most to preserve facial features, what to check in the input photo, and a simple checklist for evaluating the output. Nothing here depends on a specific tool; it applies to any model that takes a reference image plus a text instruction.

An image-to-image model treats your photo as a reference, not as a fixed asset. Everything in the frame is open to reinterpretation unless the prompt says otherwise. For headshots, the model's idea of "professional" tends to lean toward retouched studio photography, so small edits to the face are a common side effect of asking for a "professional headshot".

Each change on its own can be subtle. Together, they produce someone who looks like a relative.

A useful pattern is to split the prompt into four blocks, in this order:

Putting the preserve block before the style words matters. If the prompt opens with "professional studio headshot, flawless lighting", the model has already been pulled toward the retouched look before it reads your constraints.

[Reference] The uploaded photo is the reference and shows the person to portray. [Preserve] Keep the person exactly recognizable: face shape, features, eye shape, age, skin tone and hairline stay as in the photo. Keep real skin texture and pores. The number of people stays the same. [Change] Clothing becomes a navy blazer over a white shirt.

Background becomes a softly blurred light-grey wall. Head-and-shoulders framing, facing the camera, even soft studio light, crisp focus on the eyes, natural friendly expression. [Prohibit] Do not smooth the skin, slim the face, lighten or change the skin tone, or make the person look younger or older. Do not add text, logos or watermarks.

Enter fullscreen mode Exit fullscreen mode The bracketed labels are just for readability; you can remove them before sending.

In practice, a few specific instructions carry most of the weight:

If you want to see a full working example of this structure, the professional headshot prompt on Mona Lisa Studio is published on the page, including its preserve and no-smoothing lines, and is a reasonable starting point to adapt.

The prompt protects likeness, but the photo supplies it. Before generating, check:

Do not judge the output at thumbnail size. Open it full screen next to the original and go through:

A quick sanity test: show the result to someone who knows the person, without explanation, and ask whether anything looks off. If something has drifted, add a targeted constraint for that feature and regenerate, rather than rewriting the whole prompt.

AI headshots are fine for professional profiles, resumes and team pages. They are not suitable for passports, visas or official ID, which usually require unedited photos. Changing clothing and background is a reasonable presentation choice; changing someone's face is a misrepresentation. And only generate headshots of yourself, or of people who have explicitly agreed.

Disclosure: I'm part of the Mona Lisa Studio team; this post was drafted with AI assistance and edited by me.