When shooting with the full resolution, Tangra shows only a section of the image (the upper left corner). Especially on small screens like on Laptops. As a result, you have to search for the ROI quite laboriously, even repeating it for checking purposes. Therefore the image in Tangra should be scalable (setting a zoom factor) to show the full picture on the screen. This problem does not only occur with ROI, but also with full images, where you have to search then for the stars.
Input from Karl-Ludwig Bath, 7.3.2020:
When shooting with the full resolution, Tangra shows only a section of the image (the upper left corner). Especially on small screens like on Laptops. As a result, you have to search for the ROI quite laboriously, even repeating it for checking purposes. Therefore the image in Tangra should be scalable (setting a zoom factor) to show the full picture on the screen. This problem does not only occur with ROI, but also with full images, where you have to search then for the stars.