How to Use Lucida

Lucida runs directly in your browser. For the best experience:

• Use a desktop or laptop computer with a large screen
• Maximize your browser window or switch to full-screen mode (by clicking on the button)

Lucida can work with image files, but using a webcam pointing at your drawing surface gives you a live view of your artwork.

• Get the best camera you have. Can be any external camera or mobile device that can connect to your computer.
• Point the camera at your drawing surface and make sure the entire area is visible.
• Adjust the camera angle and distance to minimize glare and shadows. The app can help you with perspective correction, but try to avoid extreme angles!
• Make sure the camera is mounted securely and does not move (shaking is fine).
• Ensure good lighting conditions so you can clearly see both your drawing surface.

Lucida works with two media sources - one is your reference image (or video), and the other one is your own artwork. You can use them next to each other or overlay them for tracing. For the purpose of this guide, let`s assume you want to have your artwork on the right side and the reference as image file on the left side:

• Load your reference image. Click the "Select Image" button if you see it, or click on the button in the toolbar above the left pane and find the "Select Image" option.
• Load the video source for your artwork. Click on the "Use Video" button if you see it, or click on the button in the toolbar above the right pane and find your camera. NOTE: You may need to give the browser permission to access your camera. Make sure your camera is connected and recognized by your computer. Then click on "Refresh Camera List" to search for camera devices.

The camera is most likely not perfectly aligned with your drawing surface. It is now time to make some perspective adjustments:

• Click on the button in the toolbar above the video pane. A selection rectangle will appear.
• Drag the corners of the rectangle to match the corners of your drawing surface in the video or image. You can also zoom in and out for higher precision while adjusting the corners.
• Enter the actual dimensions of the selected rectangle area. This will usually be the physical size of your canvas or paper. The units do not matter as long as they are the same for both width and height. The app will use these dimensions to calculate aspect ratio and to compute accurate perspective corrections.
• Once done, click the blue "Apply" button. The app will crop the selected area and correct the perspective in real-time. You can always re-adjust it later by clicking next to the button again.
• Apply additional adjustments like brightness, contrast, and saturation () to improve visibility if needed, and make sure the artwork and the reference look as similar as possible.

Most of the time, you will want to use the app in side-by-side mode. But you can also start by tracing the reference image directly to your drawing surface:

• Click on the or button to switch to overlay and side-by-side mode.
• Drag layers round and zoom/pan them to align them for tracing. Use the button to bring a layer on top if needed.
• Pro tip — Image Synchronization: Once aligned, enable sync from the center toolbar to lock both images together. Zooming or panning one will move the other proportionally, so you never lose your alignment mid-session. Rotation and flip are synced too.
• Select your preferred tracing mode.
  • Normal: Adjust the opacity of the top layer to see both your drawing and the reference at the same time.
  • Drawing: Makes a light surface transparent. Use for dark drawings on light surfaces.
  • Negative Drawing: Makes a dark surface transparent. Use for light drawings on dark surfaces.