Because of Contextcapture limitations there is sometimes a need to place masks on some photos. For example towers with masts. The mast otherwise is lost in production as it is not possible to photo it without sky or ground and because stastitically most points are on ground then the mast is discarded as irrelevant even if it have some tie points which are more precise as ground points. The statistical approach doesn't work in theses cases.
Is there any mask tool(Bentley or 3rd party) which could be easy to use and produce mask TIF files? Using Paint or Photoshop is a slow process. Agisoft has it already implemented in Photoscan internally though the tools are also not the easiest to use. Saying that CC can do everything automatically is just a marketing and in real-life situations it doesn't always work like magic.
Also how to attach masks to existing project and loaded photos?