Character drift often starts with a thin upload. One flattering face, one hopeful prompt, then ten cousins that look “close enough” until a side profile or wardrobe change breaks the match. I ran that failure through Image to Image with Nano Banana’s up-to-four reference slot filled on purpose. The useful check is not “can AI keep a face.” It is “did you lock enough identity before you scored the output.”
Art directors and brand editors feel this first. They need a desk rule: no character sign-off until four reference photos are locked and the same brief is rerun under a new outfit or camera angle. One pretty frame is luck. Four locked references turn luck into a repeatable check you can archive with the approved prompt.
Upload Up To Four Reference Photos
On ToImage, the Nano Banana path accepts up to four reference images in the image-to-image flow. Upload the source, then fill the reference slots before you write a long transform line. The product step is short: upload → attach references → describe the change → pick the model → generate. The discipline sits in what you attach, not in how poetic the prompt sounds.
|
Reference set |
What you upload |
What you can fairly judge |
| One photo | Single flattering still | One lucky match, not identity |
| Two photos | Front plus outfit crop | Partial lock; profile still fragile |
| Four photos | Front, side, detail, lighting | Same face under new prompts |
Use the table as a gate. If you only uploaded one JPEG, you are not testing consistency. You are sampling chance. Brand desks should refuse character tickets that arrive without the four-file pack attached to the brief.
Pick Four Stills That Disagree Useful Ways
Same person, different angle, different crop, different light. Front face, strong side or three-quarter, one outfit or jewelry detail, one harsher lighting crop. Do not feed four near-duplicates of the same smile. Two smiles from the same shoot angle count as one truth, not two. If talent only sent four nearly identical selfies, ask for a profile or a detail crop before you burn the first credit.
Name the files like a kit: face-front, face-side, jacket-detail, light-harsh. Operators grab the wrong four later when the folder is a dump. A messy pack makes a fake lock even when the slot count says four. Store the pack next to the approved prompt line so the next operator does not reinvent identity from a screenshot.
Write The Transform After The Pack Is Locked
Only after the four references sit in the slots do you write the prompt. Keep it about wardrobe, background, or pose. Avoid rewriting facial geometry in the same sentence. In my testing, “keep the same face, change jacket to navy, studio softbox” beats a paragraph that also invents age, ethnicity, and expression from scratch. The references already carry identity. The prompt should not argue with them.
If you must mention expression, keep it to one short clause. Long identity essays fight the reference pack. When the output drifts, fix the pack or hop models before you rewrite the person’s bone structure in text.
Keep The Same Face Across Generations
Freeze the four-file pack. Change only the transform line or the model. If you edit references and the prompt at the same time, you cannot tell what fixed the face. One pass is exploration. Two stable passes under different wardrobe lines is a verdict you can take to a review meeting.
ToImage keeps the multi-model panel in one desk, so you can hold the same reference pack while you switch Nano Banana, Seedream, or Flux Kontext for a second opinion. You are not hunting a new face. You are checking whether identity holds when the model changes under the same locked stills. That separation—frozen pack, moving model—is what makes the experiment readable.
Rerun Under A New Outfit Or Angle
After the first good frame, change one thing: jacket color, camera height, or background. Keep the four references frozen. If hairline, eye spacing, and jaw edge hold on the second pass, you have a usable lock. If the second pass invents a cousin, the first frame was luck. Write the two prompt lines next to the pack so the next person can reproduce the check without asking you in chat.
Campaign weeks usually need more than a front smile. Profile turns, pack shots, and side light are where thin uploads fail. Build those into the second and third passes before anyone calls the character “done.”
Hop Models Without Rebuilding The Pack
If Nano Banana holds the face but softens a sleeve logo, try Flux Kontext or Seedream on the same four references instead of rewriting identity. Keep the pack frozen while you hop. Changing both model and references at once destroys the experiment. GPT-4o or Qwen Image Edit can sit in the same panel for a local cleanup after the character is approved. Use them to clean a corner, not to redefine the person. The four-slot lock remains the source of truth.
What To Check Before You Accept A Frame
Open the four references beside the new outputs. Check hairline, eye spacing, jaw edge, and any mark you care about. Pass only if two different prompts keep those marks under a new outfit or background. One perfect frame with three soft failures is still a fail for campaign use. Taste arguments shrink when the grid is visible on one screen.
- Reject packs built from near-identical crops.
- Require at least one side or three-quarter view in the four.
- Rerun after a wardrobe change before sign-off.
- Keep model hops separate from reference edits.
- Archive the four files with the approved prompt line.
If the face holds but a sleeve logo melts, treat that as a detail failure, not a character failure. Fix detail with a tighter crop in the reference pack or a model hop. Do not throw away a good identity lock because one accessory failed. That is where AI Image to Image stops being a novelty click and becomes an editorial control: four-slot lock first, pretty frame second.
Paid plans add commercial license and no watermark on paid outputs once a locked character leaves internal review. Run that check after identity passes, not before. Shipping a drifting cousin with a clean license stamp is still a failed character ticket.
Fail Signals After Four Refs Lock
Four references do not guarantee a usable face. Packs built from the same shoot angle still drift on profile. Beauty lighting alone hides soft jaw edges that break under harsh light. Approving after one generation and never retesting a profile turn is the same old lucky-frame habit with more uploads. When hairline or eye spacing still moves after a real four-file pack, stop debating taste. Rebuild the pack with a stronger side view, or hop models with the pack frozen.
Who Needs This Four Reference Workflow
Use this workflow if you sign off recurring talent, mascots, or spokespeople and need the same face across wardrobe changes. Skip it if you only need one disposable hero still for a single post. ToImage is enough evidence here because Nano Banana’s four-reference slot and same-desk model hops make the lock checkable without rebuilding the brief in five tabs. Bottom line: lock four references before you judge drift, or you are scoring luck and calling it a model comparison.