30 images sounds like quite a lot of targets under one project in my experience. The more targets you include in your project, the less performant your experience will be. This is because put simply, the technology will be carrying out it’s functionalities x times depending on the number of targets you have.
So, for example - if you had 30 targets, your experience will technically be looking for 30 images individually each render. Let’s say that 2 targets were in view and 28 were not. The image tracker will still be looking for (therefore processing the logic for) other 28 just in case they show up; and this is before, after and during the renders for your content!
For this amount of targets, I’d actually recommend using a deep-linking system. Although it may sound like some work, each experience would be self-contained and so will be much much performant, leading to a better customer experience. It also means that from a creator standpoint, you can plan your journey and troubleshoot easier. You can also theme your projects so that it ultimately looks like one cohesive experience. For more information about deep linking, click here.
Have a great day!