I have a program where I have a WritableImage attached to an ImageView within a Scene. When the size of the WritableImage is small its associated ImageView gets updated automatically when I make any changes in the image. But after my initial tests with small images I had to find out that when the image gets bigger, this does not happen anymore. See attached test program to demonstrate this behaviour. When you start the program the window should be initially blank. When you click inside the window, the image is filled with some random color. Once that is done a text line is written out and the ImageView should be updated accordingly. This works on my machine as long as the image size stays below 4000 pixels per side. When I set it to 5000 pixels there is no update anymore. This is a serious problem because images from modern digital cameras can easily exceed that limit. (My Canon 5D Mk II does)