# Constraints
There are a few things to watch out for when creating your book.
- A red X in the photo - This indicates a photo with a DPI (dots per inch) of less than 200, which is a subjective minimum for photo quality printing. This is just a warning and will not display in the book. Things to try include:
- reducing the size of the photo (thereby increasing the DPI),
- replacing the photo,
- shuffle the page layout, or
- removing the photo.
At this time it's not possible to add or replace photos in TrackMyTour Books. If you need to add or replace a photo then do it on your map (using the app or website) and start a new TrackMyTour Books project.
- Text with a red background - This indicates a caption or title extends beyond the bounds of the space allocated to it. Things to try include:
- increasing the size of the allocated space,
- moving the text to its own page,
- shuffling the page layout,
- reducing the font size,
- editing (by double clicking) and reducing the text content, or
- removing the text completely.