Move to the level of the map hierarchy that you want to render.
Right-click the sample slot and choose Render Map from the pop-up menu.
3ds Max opens the Render Map Dialog.
Choose Single or the range of frames to render.
In the Dimensions group box, specify the pixel resolution to render to.
Click the Files button, and specify a path and file name for the file. Make sure Save To File is on unless you want to see the image only in a Rendered Frame Window.
Click Render.
A Rendered Frame Window appears displaying the map. If Save To File is on, the image is also saved to disk.