Chris Malikoff mentioned a virtual camera lucida for the iPhone and iPad, called appropriately enough Camera Lucida. It looked very interesting (video tutorial here), so I decided to give it a quick try. It really works well.
The app overlays an image you select on the iPad’s (or iPhone’s) video feed. So you have a static reference image, and you can see your pencil drawing in the video. It takes a bit of effort to coordinate this, but within a few minutes, it starts to feel natural. But as with the NeoLucida, the more time you spend doing it, the better you get.
Here is the setup I used (click image for full size version):
I taped the iPad to an upside-down vase, with the camera lens hanging out over my drawing paper. I used a lamp to illuminate the paper, but positioned it so it doesn’t shine on the iPad screen. You can get a rundown of the app’s features in the video tutorial provided by the manufacturer. The basic workflow is simple: select an image already on your device (or in the cloud), or take an image with the camera (great for en plein air! (French for painting outside)). You can adjust focus, rotation, zoom, and transparency of the original image.
Once you have it set up, just draw. You can see my drawing in the image above (click to zoom it to full size), and here is a view looking down into the app:
You can also click this image to see it full size. As you can see from the resulting drawing, which took about 10 minutes, it works extremely well. The big advantage is the large field of view–and you can zoom to work on details. It may well be the best camera lucida you can get! I haven’t tried the LUCID-Art yet, but I have a hunch this virtual camera lucida is pretty close to ideal, and costs $5. However, you might want to invest in a gooseneck iPad or iPhone holder to make it a little easier to use, in case you don’t happen to have a ready-made stand handy!
Recommendation: get it. It’s a blast.