The AI image editing space has never been more crowded, yet a persistent pain point continues to plague all content creators: subject consistency. Whether it's Midjourney's redrawing or the complex LoRA training of Stable Diffusion, maintaining a character's facial features, clothing, and even their essence without “catastrophic” distortion across different scenes and actions has always been a daunting challenge.

But I believe the solution to this challenge may finally be here.

Recently, a mysterious model dubbed “Nano banana” has been circulating wildly within the community. Its true identity? Google's newly released Gemini 2.5 Flash Image. After all-night testing across over 100 cases, the conclusion is clear: it stands as the most powerful AI image editing model available today, flawlessly resolving the subject consistency conundrum.

Currently, there are two official ways to use it (free of charge):

1. Use it in Gemini, available at: https://gemini.google.com/

1. Use it in AI Studio, available at: https://aistudio.google.com/

In this in-depth review, we won't limit ourselves to simple “voice-controlled image editing.” Instead, we'll comprehensively analyze this tool's true capabilities through 6 core features and 10 real-world case studies. We'll also provide directly reusable prompt templates, empowering you to get started immediately and revolutionize your creative workflow.

I. Core Capability: Unprecedented Subject Consistency

This represents Gemini 2.5 Flash Image's most revolutionary feature. By employing partial repainting instead of full-scale redrawing, it ensures astonishing consistency in the core subject across multiple edits and generations. We tested this through the following scenarios.

Test 1: Single Character Sequential Storyboard

• Test Objective: Verify the model's ability to maintain a single character's appearance across different scenes and actions.

• Procedure: Upload a character concept art image + input prompts.

• Original Character Concept Art:

• 【Specific Prompt】 A cyberpunk female hacker sits in a room filled with monitors, her fingers flying across a glowing keyboard. Blue data streams reflect off her face. The backdrop is a futuristic cityscape at night, with neon lights flickering outside the window. The atmosphere is tense and focused.

• Evaluation: The character's facial features, clothing, and key characteristics maintain remarkable consistency across different angles and lighting conditions. This represents a groundbreaking solution to the randomness issues plaguing previous models.

Test 2: Multi-Character Batch Storyboard Generation

• Test Objective: Upload multiple character reference images to generate a continuous storyboard featuring these characters in a single batch.

• Procedure: Upload 2 or more character images + input instructions.

• Original Character Images:

• 【Specific Prompt】Using the two character reference images provided (knight and mage), create a series of storyboards depicting their fantasy adventure exploring ancient ruins. The overall style should evoke an epic fantasy film aesthetic with strong light-dark contrasts. Generate 4 sequential storyboard panels depicting their journey: discovering the ruin's entrance, solving traps, confronting guardians, and ultimately finding the treasure. Maintain consistent character designs throughout. Use a horizontal 16:9 aspect ratio for each panel.

• Evaluation: Both character designs were well-preserved, and the AI demonstrated an understanding of narrative sequencing. The only drawback is that aspect ratios occasionally prioritized reference images over prompts, though this minor flaw does not detract from the overall quality.

II. Advanced Techniques: Precise Control from Sketches to Storyboards

Test 3: Controlling Stick Figure Sketch Actions

• Test Objective: Verify the model's ability to interpret simple “stick figure” sketches and transform them into complex, character-appropriate dynamic visuals.

• Procedure: Upload character image + sketch + input prompt.

• Original Reference Image:

• 【Specific Prompt】A ballet dancer leaps in an elegant pose as shown in the [reference sketch], set against the backdrop of a classical theater stage. A spotlight beams down upon her, with her skirt unfurling in midair. Set the aspect ratio to 3:4.

• Evaluation: The model's ability to interpret abstract sketches is astonishing. It not only recreates the actions but also adds contextually relevant details and interactions, truly becoming a creative accelerator.

III. Commercial Applications: E-commerce Outfit Swapping and Multi-Image Fusion

Test 4: Model Outfit Swapping

• Test Objective: “Dress” specified clothing onto designated models to evaluate practicality in e-commerce scenarios.

• Procedure: Upload model image + clothing image + input instructions.

• Original Source Images:

• 【Specific Prompt】Dress the female model in this Hawaiian-style beach shirt, replace the background with a sunny beach, and maintain vibrant colors throughout the image.

• Review: The wrinkles, lighting, and model's posture blend exceptionally naturally. For the e-commerce industry requiring rapid generation of large volumes of product display images, this is undoubtedly revolutionary.

Test 5: Product Replacement

• Test Objective: Replace the specific product held by the model while keeping the background and model unchanged.

• Procedure: Upload scene image + product image + input command.

• Original Source Images:

• 【Specific Prompt】Keep the model's facial expression and seated posture unchanged. Replace the book she is reading with the provided tablet, and illuminate the screen to display a web interface.

• Evaluation: The replacement process was seamless, with AI accurately handling hand poses and light reflections on new objects. The workflow of composing the scene first and then swapping products was exceptionally smooth.

IV. “Editing Images with Your Voice”: The Revolution in Text-Based Editing

Test 6: Scene/Clothing Replacement

• Test Objective: Modify most image elements using text commands alone.

• Steps: Upload image + Enter command.

• Original Reference Image:

• 【Specific Prompt】Replace the man's T-shirt in the image with a retro astronaut suit, and change the background to the lunar surface with Earth visible in the distance.

• Evaluation: True “partial repainting.” The subject's pose and facial expressions remain perfectly preserved while the background and clothing are completely replaced—effectively achieving Photoshop-level editing with a single command.

Test 7: Portrait Retouching

• Test Objective: Evaluate the model's capability in portrait retouching, such as adding glasses, removing facial hair, and smoothing wrinkles.

• Steps: Upload image + Enter prompt.

• Original Reference Image:

• 【Specific Prompt】Add a pair of stylish black sunglasses to the person in the image, with the lenses reflecting the seaside scenery.

• Evaluation: The retouching results appear remarkably authentic, with no visible signs of AI processing. The AI demonstrates a deep understanding of facial structure.

Test 8: Old Photo Restoration and Coloring

• Test Objective: Restore aged, damaged photos and apply colorization.

• Procedure: Upload vintage photo + input instructions.

• Original Source Image:

• 【Specific Prompt】Restore this yellowed graduation photo by removing mold spots and creases. Apply colorization with the following specifications: - Natural skin tones for subjects - Red brick walls in the background - Blue sky - Dark blue academic robes for each person

• Review: The results are truly stunning. Not only does it repair physical damage, but it also intelligently fills in details and applies period-appropriate coloring, making complex restoration accessible to everyone.

V. Style Transfer and Creative Generation

Test 9: Image Style Conversion

• Test Objective: Convert realistic photos into specific artistic styles.

• Steps: Upload image + Enter prompt.

• Original Reference Image:

• 【Specific Prompt】Transform this cityscape photo into an oil painting in the style of Van Gogh's “Starry Night.”

• Review: The style transfer is exceptionally thorough while preserving the original image's compositional essence. It transcends a simple filter, instead reimagining the entire scene through a fresh artistic language.

Test 10: Photo to Figurine

• Test Objective: Convert a real photograph into a high-quality figurine model image complete with packaging.

• Steps: Upload image + Enter prompt.

• Original Reference Image:

• 【Specific Prompt】Transform this anime character photo into a clay-style figurine. Position the figurine on a wooden workbench, with sculpting tools and colored clay nearby. Use a blurred indoor studio as the background. Ensure the figurine conveys a handcrafted texture.

• Evaluation: The texture of materials (such as PVC and clay) is rendered with remarkable precision. The model even grasps the concept of “product display,” creatively constructing complete scenes that incorporate packaging, accessories, and environmental elements.

VI. Practical Tips and Considerations

• Regarding Chinese Prompts: For tasks requiring precise knowledge, such as object annotation, translating prompts into English yields better results.

• Regarding Size Control: Uploading reference images to fix dimensions is more stable than controlling via prompts. Generated image size = uploaded image size.

• Regarding Prompt Details: While prompts needn't be overly complex, more specific and detailed instructions often yield better results.

• Regarding Clarity: Current image clarity has room for improvement, likely due to computational limitations. We anticipate higher-resolution versions in future releases.

Conclusion: AI Is Ultimately Just a Tool

The emergence of Gemini 2.5 Flash Image represents a paradigm shift in AI image editing. It tackles the industry's biggest pain point in an extremely straightforward manner, directly challenging the dominance of Stable Diffusion and Photoshop.

It liberates professional creators from tedious “consistency” battles while empowering ordinary users to achieve professional-grade photo editing with just “one sentence and one image.” This represents true cost-saving efficiency gains with commercial value—the most practical productivity tool in the AI era.

Of course, tool evolution never stops. But remember: AI is ultimately just a tool. Don't get hijacked by the “replacement” narrative. True value always lies with you—the one who knows how to use tools, think critically, and articulate clear needs.

Finally, I'd love to hear your thoughts: Which industry do you think Nano banana (Gemini 2.5 Flash Image) will disrupt the most? Share your insights in the comments below!