A texture can be used to define the color pattern on an emitter.
This option allows you to texture an emitter with a MXI, HDR or EXR image (all three are high dynamic range formats). The Intensity parameters works as a multiplier of the texture intensity, allowing you to adjust the power of your emission.
You can also use low dynamic range image (LDR), such as a jpeg, by first converting it from 8 bits to 32 bits using an image editing application, or Maxwell.exe. Simply open the image using File>Load Image and once the image is loaded go to File>Save MXI. You can also use Photoshop or any other image processing software to convert a LDR image into EXR or HDR formats. Obviously, the LDR image won't get a higher dynamic range after this conversion, but being in a high dynamic range format allows that image to be used in an emitter.
You can also use Maxwell.exe to adjust the intensity of the MXI, HDR or EXR map using the Intensity slider in the MXI section (found in the Edit panel). Simply open your low-dynamic bitmap in the core rendering engine and save it to the MXI format. Maxwell Render will automatically convert your image to a high-dynamic range image. You can use the f-Stop and Intensity sliders to adjust your emitting image intensity.
Textured emission using a high dynamic range image