Quickly calibrate your sewing projector with a measuring tape

I've been working on a new calibration feature that eliminates the need for a cutting mat. After several months of experimentation, I've developed a simple solution that only requires a measuring tape.

How It Works

The new calibration method is straightforward: you measure five key dimensions of your projection area (top, bottom, both sides, and one diagonal). With these measurements, the app can accurately calculate the projection geometry. The whole process takes less than two minutes once you get the hang of it.

Development

Initially, I was focused on creating an AR-based calibration system that would use your device's camera to detect the projection area automatically. While that's still a work in progress, it's not quite accurate enough yet for real-world use. Rather than waiting until that's perfect, I wanted to provide something helpful now.

This new approach calibrates a large area quickly with just a measuring tape. My original intent was to calibrate the entire projection area, but I discovered that on some devices, parts of the screen get clipped on the projector. This new method works within those constraints while still giving you the largest possible calibrated area. This method work best when projecting on the floor or on a large enough table that most of the projection is visible on the flat surface. 

Coming Up

I'll be including this feature in the next app update. It's been thoroughly tested on various setups, and I'm happy with how it's performing. This should make the calibration process more accessible, especially for users who don't have a proper cutting mat available or when cutting mats are slightly warped.