Photoshop: Working on Detail with a Broader View at the Same Time
Often, while working on processing an image, it is useful to work on detail in a small part of the image and see the larger image at the same time to enable you to see the effects of the changes you are making in the broader context of the image. For example, one might be working on the area around the eye in a portrait where it would be useful to see the whole portrait at the same time. Of course one can do this with multiple monitors but I believe it is more useful to see both at the same time without changing one's gaze to a different monitor. Here's how to do it easily in PS:
1. Open Your Image
2. Open the image you are working on (opened in #1 above) again by going to the Window menu in PS>Arrange>New Window
3. Tile both windows by going to the Window Menu again>Arrange>Tile and then pick the orientation - Horizontal or Vertical to suit the image you're working on
4, Now, with those two windows, one of them can be resized to any size, enabling work on detail, while the other window provides a view to the whole image.