AI Image Generation: DALL-E, Midjourney, and Stable Diffusion

Published: January 5, 2025 | Reading time: 11 minutes

AI Generated Art

The first time I saw an AI-generated image, I thought it was a trick. It was 2022, and someone had typed "an astronaut riding a horse in space" into DALL-E 2. What came back was stunning—not photorealistic, but stylistically beautiful, with strange and wonderful details I didn't expect.

That was the moment I realized generative AI wasn't coming—it was already here. Let me explain how these tools work and what makes each one special.

How AI Image Generation Works

Before comparing tools, let me explain the underlying technology. Modern AI image generation relies primarily on two approaches: diffusion models and their variants.

Diffusion Models: The Core Idea

Here's the elegant insight: what if you learned to denoise images instead of generating them directly?

Diffusion models work by:

  1. Forward process: Take an image and gradually add noise until it's just random noise
  2. Reverse process: Train a neural network to undo this process—to remove noise and reconstruct the image

Once trained, you can start with random noise and let the model progressively denoise it into an image.

Adding Text Control

The magic is adding text conditioning. During training, the model learns which text prompts correspond to which images. Then at generation time, your text prompt guides the denoising process toward the desired output.

This is why you can type "a cat wearing a top hat" and actually get one.

DALL-E: OpenAI's Offering

DALL-E was the first widely accessible AI image generator. Released in early 2021, DALL-E 2 (2022) brought major improvements in quality and capabilities.

Strengths:

Limitations:

DALL-E feels polished and safe—great for commercial applications where you need predictable results.

Midjourney: The Artist's Choice

Midjourney has become the darling of artists and designers. It produces images with a distinctive, often ethereal quality that many find beautiful.

Access is via Discord—you type prompts in a channel and get images back. This community-driven approach has created a culture of prompt sharing and experimentation.

Strengths:

Limitations:

Midjourney is my go-to when I want something artistic and unique. It rewards experimentation.

Stable Diffusion: The Open Source Champion

Stable Diffusion changed the game by making image generation accessible to anyone with a decent GPU. Released by Stability AI, it's open source—you can run it locally, modify it, and build on top of it.

Strengths:

Limitations:

Stable Diffusion is perfect for developers, researchers, and anyone who wants maximum control.

Key Concepts

Prompts

Text descriptions guide generation. But there's art to prompts:

Example: "a cyberpunk city at night, neon lights, rain-slicked streets, cinematic lighting, 8k, unreal engine render"

Negative Prompts

Tell the model what you DON'T want. "low quality, blurry, ugly, distorted" helps avoid common issues.

Steps

More steps = more detail = longer generation. 20-50 steps is typical.

CFG Scale

Classifier-Free Guidance controls how closely the image follows your prompt. Too low = ignores prompt. Too high = distorted.

Seed

Random starting noise. Same seed + same prompt = reproducible results.

Real-World Applications

AI image generation is being used for:

Challenges and Concerns

It's not all positive. Here are real concerns:

1. Copyright and Ownership

Who owns AI-generated images? The user? The company? The artists whose work trained the model? This is legally unclear.

2. Artist Displacement

Will AI replace illustrators? More likely it will augment them, but transition is painful.

3. Misinformation

Creating fake images of real people is increasingly easy. This has implications for politics, fraud, and harassment.

4. Bias

Models reflect training data biases—often encoding stereotypes about gender, race, and culture.

5. Environmental Impact

Training and running these models consumes significant energy.

The Future

Where is this heading? Some trends:

Getting Started

If you want to try AI image generation:

  1. Start with DALL-E or Bing Image Creator (free, easy)
  2. Try Midjourney if you want artistic results
  3. Install Stable Diffusion if you're technical
  4. Study prompts—learn what works
  5. Iterate—generation is a creative process

Final Thoughts

AI image generation represents a fundamental shift in creativity. It's not about replacing human artists—it's about democratizing visual imagination. Anyone can now create images from their imagination.

The technology is still evolving. Quality improves constantly. New capabilities emerge. But we're witnessing something genuinely transformative in how humans create and communicate visually.