# Nano Banana — Prompt-Strategien im Detail

Alle Strategien basieren auf der offiziellen Google Gemini API Dokumentation.
Default-Modell für alle Beispiele: `gemini-3.1-flash-image-preview` (Nano Banana 2).

---

## Grundprinzip

> **"Describe the scene, don't just list keywords."**
> Die Stärke des Modells liegt in seinem tiefen Sprachverständnis. Ein narrativer,
> beschreibender Absatz liefert fast immer ein besseres, kohärenteres Bild als
> eine Stichwortliste.

---

# A. TEXT-ZU-BILD STRATEGIEN

## 1. Fotorealistische Szenen

Fotografische Fachbegriffe verwenden: Kamerawinkel, Objektiv, Beleuchtung, Textur.

**Vorlage:**
```
A photorealistic [shot type] of [subject], [action or expression], set in [environment].
The scene is illuminated by [lighting description], creating a [mood] atmosphere.
Captured with a [camera/lens details], emphasizing [key textures and details].
The image should be in a [aspect ratio] format.
```

**Nützliche Begriffe:**
- Shot types: `close-up portrait`, `wide-angle shot`, `aerial view`, `over-the-shoulder`, `eye-level`, `macro shot`, `low-angle perspective`
- Lighting: `golden hour`, `soft diffused light`, `three-point softbox`, `dramatic rim lighting`, `overcast natural light`, `studio strobe`
- Lens: `85mm portrait lens` (Bokeh), `35mm wide`, `200mm telephoto`, `macro lens`
- Mood: `serene`, `dramatic`, `intimate`, `melancholic`, `vibrant`, `nostalgic`
- Qualität: `ultra-realistic`, `sharp focus on [detail]`, `award-winning photography`

**Vollständiges Beispiel (aus offizieller Doku):**
```
A photorealistic close-up portrait of an elderly Japanese ceramicist with deep,
sun-etched wrinkles and a warm, knowing smile. He is carefully inspecting a freshly
glazed tea bowl. The setting is his rustic, sun-drenched workshop with pottery wheels
and shelves of clay pots in the background. The scene is illuminated by soft, golden
hour light streaming through a window, highlighting the fine texture of the clay and
the fabric of his apron. Captured with an 85mm portrait lens, resulting in a soft,
blurred background (bokeh). The overall mood is serene and masterful.
```

---

## 2. Stilisierte Illustrationen, Sticker & Icons

Stil explizit benennen. Für 3D-Icons: "colorful and tactile 3D style" verwenden.

> **Tipp: Transparenter Hintergrund** — Für Sticker/Icons mit echtem Alpha-Kanal nutze
> `--transparent-bg` (`-t`). Der Prompt wird automatisch um eine Chroma-Key-Anweisung
> erweitert und der Hintergrund nachgelagert durch Transparenz ersetzt.

**Vorlage:**
```
A [style] sticker/illustration/icon of [subject], featuring [key characteristics]
and a [color palette]. The design should have [line style] and [shading style].
The background must be [transparent / white / color].
```

**Verfügbare Stile:**
- `kawaii` (japanisch niedlich), `chibi`, `anime`, `manga`
- `flat design`, `material design`, `isometric`
- `watercolor`, `oil painting`, `pencil sketch`, `ink drawing`
- `retro/vintage (80s, 90s)`, `neon cyberpunk`, `lo-fi`
- `minimalist`, `geometric`, `low poly`
- `colorful and tactile 3D style` (empfohlen für Icons/Sticker)

**Beispiel Sticker:**
```
A kawaii-style sticker of a happy red panda wearing a tiny bamboo hat. It's munching
on a green bamboo leaf. The design features bold, clean outlines, simple cel-shading,
and a vibrant color palette. The background must be white.
```

**Beispiel 3D Icon (aus offizieller Doku):**
```
An icon representing a cute dog. The background is white.
Make the icons in a colorful and tactile 3D style. No text.
```

---

## 3. Text im Bild — Logos, Menüs, Infografiken

Gemini rendert Text sehr gut. Nano Banana 2 unterstützt das, Nano Banana Pro ist besser
für hochwertige kommerzielle Assets mit Text.

**Vorlage:**
```
Create a [image type] for [brand/concept] with the text "[exact text]" in a [font style].
The design should be [style description], with a [color scheme].
```

**Tipps:**
- Text **immer** in Anführungszeichen angeben: `the text "The Daily Grind"`
- Schriftstil beschreiben: `bold sans-serif`, `elegant serif`, `handwritten script`, `typewriter`
- Farbschema: monochrom, Komplementärfarben, Markenfarbpalette
- Layout: `circular`, `horizontal`, `stacked`, `badge style`
- Für komplexe Layouts: erst Text generieren, dann Bild mit Text anfragen

**Beispiel Logo:**
```
Create a modern, minimalist logo for a coffee shop called 'The Daily Grind'.
The text should be in a clean, bold, sans-serif font. The color scheme is black and white.
Put the logo in a circle. Use a coffee bean in a clever way. Aspect ratio 1:1.
```

**Beispiel Magazin-Cover (aus offizieller Doku):**
```
A photo of a glossy magazine cover, the minimal blue cover has the large bold words
"Nano Banana". The text is in a serif font and fills the view. No other text. In front
of the text there is a portrait of a person in a sleek and minimal dress. She is
playfully holding the number 2, which is the focal point.
Put the issue number and "Feb 2026" date in the corner along with a barcode. The magazine
is on a shelf against an orange plastered wall, within a designer store.
```

---

## 4. Produkt-Mockups & kommerzielle Fotografie

Für E-Commerce, Werbung, Branding. Studiobeleuchtung und Winkel genau beschreiben.

**Vorlage:**
```
A high-resolution, studio-lit product photograph of [product description] on a
[background surface]. The lighting is a [lighting setup] to [lighting purpose].
The camera angle is a [angle] to showcase [specific feature]. Ultra-realistic,
with sharp focus on [key detail]. [Aspect ratio].
```

**Hintergründe:** polierter Beton, weißes Seamless-Papier, Holztisch, Marmor, Glas, Acryl
**Beleuchtung:** Three-Point Softbox (eliminiert Schatten), Rim Light (Kontur), Backlight
**Winkel:** 45°-Erhöhung, direkt von oben (Flatlay), seitlich, frontal

**Beispiel (aus offizieller Doku):**
```
A high-resolution, studio-lit product photograph of a minimalist ceramic coffee mug
in matte black, presented on a polished concrete surface. The lighting is a three-point
softbox setup designed to create soft, diffused highlights and eliminate harsh shadows.
The camera angle is a slightly elevated 45-degree shot to showcase its clean lines.
Ultra-realistic, with sharp focus on the steam rising from the coffee. Square image.
```

---

## 5. Minimalistisch & Negativraum

Ideal für Präsentations-Hintergründe oder Marketing-Materialien mit Text-Overlay.

**Vorlage:**
```
A minimalist composition featuring a single [subject] positioned in the [position] of
the frame. The background is a vast, empty [color] canvas, creating significant negative
space [for text overlay]. Soft, subtle [lighting direction] lighting. [Aspect ratio].
```

**Positionierungen:** `bottom-right`, `top-left`, `center`, `lower-third`, `upper-third`
**Hintergrundfarben:** `off-white`, `soft gray`, `deep navy`, `pale cream`, `light sage`

**Beispiel:**
```
A minimalist composition featuring a single, delicate red maple leaf positioned in the
bottom-right of the frame. The background is a vast, empty off-white canvas, creating
significant negative space for text. Soft, diffused lighting from the top left. Square image.
```

---

## 6. Comic & Storyboard (Multi-Panel)

Charakterkonsistenz und Szenenbeschreibung sind entscheidend. Am besten mit Referenzbild.

**Vorlage:**
```
Make a [X] panel comic in [art style]. Put the character in a [type of scene].
```

**Verfügbare Stile:** `gritty noir` (schwarz-weiß, hoher Kontrast), `manga` (screentones),
`franco-belgian` (klare Linien, Farbe), `silver age comics` (Rasterfarben),
`webcomic` (flache Farben)

**Beispiel (mit Referenzbild des Charakters, aus offizieller Doku):**
```
Make a 3 panel comic in a gritty, noir art style with high-contrast black and white inks.
Put the character in a humorous scene.
```
→ Referenzbild des Charakters als `input_image` mitgeben

---

## 7. Google Search Grounding (Echtzeit-Daten)

Für Visualisierungen basierend auf aktuellen Ereignissen, Wetter, Sportergebnisse.
Nano Banana 2 unterstützt zusätzlich **Image Search** (Bilder aus dem Web als Kontext).

**Web Search (alle Modelle außer NB1):**
```
tools=[{"google_search": {}}]
```

**Image Search (nur Nano Banana 2):**
```python
tools=[types.Tool(google_search=types.GoogleSearch(
    search_types=types.SearchTypes(
        web_search=types.WebSearch(),
        image_search=types.ImageSearch()
    )
))]
```

**Beispiel Web Search (aus offizieller Doku):**
```
Visualize the current weather forecast for the next 5 days in Berlin as a clean,
modern weather chart. Add a visual on what I should wear each day.
```
→ `aspect_ratio="16:9"`, `tools=[{"google_search": {}}]`

**Beispiel Image Search (aus offizieller Doku):**
```
A detailed painting of a Timareta butterfly resting on a flower.
```
→ Mit Image Search sucht das Modell echte Bilder als visuelle Referenz.

**Beispiel Sport-Grafik:**
```
Make a simple but stylish graphic of last night's Arsenal game in the Champions League.
```

⚠️ **Pflichtanforderung bei Image Search:** Quellen-Attribution mit klickbarem Link zur
Quellwebseite muss dem User angezeigt werden. Die `groundingMetadata.searchEntryPoint`
aus der Antwort enthält fertiges HTML dafür.

---

# B. BILD-ZU-BILD STRATEGIEN (Bildbearbeitung)

Bei allen Bearbeitungsaufgaben: `input_image` mitgeben + klare Anweisung.

## 8. Elemente hinzufügen / entfernen

**Vorlage:**
```
Using the provided image of [subject], please [add/remove/modify] [element] to/from
the scene. Ensure the change [description how to integrate]. Keep everything else identical.
```

**Beispiel (aus offizieller Doku):**
```
Using the provided image of my cat, please add a small, knitted wizard hat on its head.
Make it look like it's sitting comfortably and not falling off.
```

---

## 9. Inpainting — Einzelne Bereiche gezielt ändern

Spezifischen Bereich benennen, Rest explizit unverändert lassen.

**Vorlage:**
```
Using the provided image, change only the [specific element] to [new description].
Keep everything else in the image exactly the same, preserving the original style,
lighting, and composition.
```

**Beispiel (aus offizieller Doku):**
```
Using the provided image of a living room, change only the blue sofa to be a vintage,
brown leather chesterfield sofa. Keep the rest of the room, including the pillows on
the sofa and the lighting, unchanged.
```

---

## 10. Style Transfer — Kunststil übertragen

Original-Komposition beibehalten, Stil komplett ändern.

**Vorlage:**
```
Transform the provided photograph of [subject] into the artistic style of
[artist/art style]. Preserve the original composition but render it with
[description of stylistic elements].
```

**Beispiel (aus offizieller Doku):**
```
Transform the provided photograph of a modern city street at night into the artistic
style of Vincent van Gogh's 'Starry Night'. Preserve the original composition of
buildings and cars, but render all elements with swirling, impasto brushstrokes and
a dramatic palette of deep blues and bright yellows.
```

---

## 11. Advanced Composition — Mehrere Bilder kombinieren

Bis zu 14 Referenzbilder (NB2: 10 Objekte + 4 Charaktere; NB Pro: 6 Objekte + 5 Charaktere).

**Vorlage:**
```
Create a new image by combining the elements from the provided images. Take the
[element from image 1] and place it with/on the [element from image 2]. The final
image should be a [description of final scene].
```

**Beispiel Fashion-Komposition (aus offizieller Doku):**
```
Create a professional e-commerce fashion photo. Take the blue floral dress from the
first image and let the woman from the second image wear it. Generate a realistic,
full-body shot of the woman wearing the dress, with the lighting and shadows adjusted
to match the outdoor environment.
```

---

## 12. High-Fidelity Detail Preservation

Wichtige Details (Gesicht, Logo) explizit schützen. Bei Logo auf Kleidung etc.

**Vorlage:**
```
Using the provided images, place [element from image 2] onto [element from image 1].
Ensure that the features of [element from image 1] remain completely unchanged. The
added element should [description of integration].
```

**Beispiel Logo auf Shirt (aus offizieller Doku):**
```
Take the first image of the woman with brown hair, blue eyes, and a neutral expression.
Add the logo from the second image onto her black t-shirt. Ensure the woman's face and
features remain completely unchanged. The logo should look like it's naturally printed
on the fabric, following the folds of the shirt.
```

---

## 13. Sketch-to-Life — Skizze → fertiges Bild

Rough Sketch in poliertes Rendering verwandeln.

**Vorlage:**
```
Turn this rough [medium] sketch of [subject] into a [style description] photo.
Keep the [specific features] from the sketch but add [new details/materials].
```

**Beispiel (aus offizieller Doku):**
```
Turn this rough pencil sketch of a futuristic car into a polished photo of the
finished concept car in a showroom. Keep the sleek lines and low profile from the
sketch but add metallic blue paint and neon rim lighting.
```

---

## 14. Character Consistency — 360°-Ansichten

Charakter von verschiedenen Winkeln darstellen. Vorher generierte Bilder als Referenz mitgeben.

**Vorlage:**
```
A studio portrait of [person] against [background], [looking forward / in profile
looking right / from above / etc.]
```

**Workflow für 360°-Serie:**
1. Erstes Bild generieren (Frontalansicht)
2. Generiertes Bild als Referenz mitgeben
3. Nächste Perspektive anfordern → Konsistenz bleibt erhalten

**Beispiel (aus offizieller Doku):**
```
A studio portrait of this man against white, in profile looking right.
```

---

# C. ALLGEMEINE QUALITÄTS-BOOSTER

Diese Phrasen verbessern die Ausgabe modell-übergreifend:

```
Ultra-realistic, sharp focus on [detail]
Highly detailed, professional quality
Award-winning photography / illustration
Cinematic color grading
Perfect composition, rule of thirds
Photorealistic render, 8K detail
```

---

# D. SEMANTISCHE NEGATIVE PROMPTS

Statt Verbote → positive Beschreibungen des Gewünschten:

| Statt... | Besser... |
|---|---|
| "no cars" | "an empty, deserted street with no signs of traffic" |
| "no text" | "purely visual, no typography or text elements" |
| "no shadows" | "evenly lit, flat lighting with minimal shadows" |
| "no people" | "a serene, uninhabited landscape" |

Bei Bearbeitungen immer hinzufügen:
```
Do not change any other elements of the image.
Keep everything else exactly the same.
```

---

# E. MULTI-TURN ITERATION (Conversational Editing)

Nano Banana 2 und Pro unterstützen Multi-Turn Chat. Bild weiterentwickeln:

1. Erstes Bild generieren
2. Im selben Chat weitermachen: `"Update this to be in Spanish. Do not change anything else."`
3. Bei NB Pro werden Thought Signatures automatisch vom SDK verwaltet
4. Aspect Ratio und Resolution können per Turn geändert werden

**Beispiel Folgeanweisungen:**
- `"That's great, but make the lighting warmer"`
- `"Keep everything, but change the character's expression to be more serious"`
- `"Change the aspect ratio to 16:9 and increase resolution to 2K"`
- `"Add some fog in the background"`

---

# F. MODELL-SPEZIFISCHE TIPPS

## Nano Banana 2 — Thinking Level optimal einsetzen

```python
# Schnell, niedrigste Latenz (Standard)
thinking_level = "minimal"

# Für komplexe Szenen mit vielen Elementen
thinking_level = "high"
```
→ `"high"` empfohlen für: Infografiken, komplexe Kompositionen, präzise Text-Layouts, Comic-Panels

## Nano Banana 2 — Image Search nutzen

Ideal wenn der User nach echten Tier-/Pflanzen-/Objekt-Bildern als Basis fragt:
- "Zeig mir einen Quetzal-Vogel als Wallpaper" → Image Search aktivieren
- "Erstelle ein realistisches Bild eines Timareta-Schmetterlings" → Image Search aktivieren

## Nano Banana Pro — Wann wirklich sinnvoll

Nur wenn der User explizit Pro möchte oder folgende Features benötigt:
- Thinking-Prozess sichtbar machen (Thought Images in der Antwort)
- Professionelle Asset-Produktion mit sehr hoher Textgenauigkeit (Werbung, Print)
- Mehr als 4 Charakter-Referenzbilder (bis 5)
- Projekte wo "Gemini 3 Pro" explizit erwähnt wird
