When attaching the lens adapter onto your device, you should look through the adapter and ensure
it is centred on the device’s camera lens. Also look from the side to ensure it is sitting flat.
Some devices have camera bumps which make it difficult to position the clip so it doesn’t cover the screen but ensures the adapter sits flat. In these cases we recommend finding a way to provide a larger flat surface for the adapter to sit on. Some device cases might help work well for this, or you could cut out some of the excess cardboard from the sheet of world pointcodes and make something specific for your device.
If the lens adapter is not centred on the camera or is not sitting flat it will affect the quality of tracking and may also prevent you completing the lens calibration process. One way of visually checking the quality of your lens calibration is to look back at the grid after successfully calibrating the lens, for example in Build Map mode as Simon did at around 7:30 in the video above. If the straight lines are straight, you are good to go. Otherwise check the lens positioning and try calibrating again.
On iOS we recommend entering the cog menu, deselecting Auto Focus, and manually choosing a focus position for your device. Aim to set a focus point that gives sharp focus for the pointcodes when they're 1-2 metres away. Do this after attaching the lens adapter but before the calibration process. This is explained at around 5:50 in the walkthrough.
On Android, camera control is a little different to the iOS build. You should tap the AF icon to lock the focus when looking at
something a couple of metres away. Then tap the lock icon to switch to a short exposure mode that should give less blur and hence
better tracking, as long as your device offers the necessary manual camera APIs.
Whenever the full-screen menu is displayed we stop the camera feed to avoid wasting resources.
Unfortunately the focus and exposure lock settings do not persist across a camera restart, so you’ll need to do the AF and lock procedure whenever you enter the camera view from the menu (i.e once at the start of the map building process, and then again when you launch an experience from the menu).