If you know Maya, it has a Render View with very useful features.
From Maya docs:
- Snapshot
A wireframe snapshot is taken of your scene and loaded as a background into the Render View. You can then marquee a region to render in front of the snapshot background
- Render Region
Allows you to draw a marquee around an area in the Render View window that you want to render. This is useful if you've made a change that you want to perform a quick test render on.
- Keep Image in Render View
Keeps the current image so you can view it later. When you keep more than one image, a slider appears at the bottom of the window, letting you bring a specific image into view without loading the image. The images are lost when you end your Maya session.
- Remove Image from Render View Releases the currently-viewed image (and the memory needed by it) from the Render View. Select the image that you want to remove by using the slider
In the latest Maya versions, when you "keep a image" it adds an overlay text with information (renderer, resolution, etc) and what is more important render time, so this way you can compare images with different values and check render times very easily.
Render Region is like "crop" option but drawing the area interactively.
The current render view implementation in the Technology Preview is pretty basic. We will definitely be making improvements for the final release and will be taking these and other suggestions into account. We do particularly want to have a multi-image viewer and "draw crop region" feature.
- Oshyan