Why does the image appear in the render brighter (burnt) than the in preview?
This is usually as a result of your render mode/settings not being in alignment with your realtime settings (usually because you're rendering in Advanced mode). If you can share a screencap of your "Lighting" tab as well as your "Options" tab under the Render window it would be helpful. Regardless, I'd start there-- if you're rendering using Advanced, results can vary drastically. Your best bet for matching the look of your viewport is to render with Maximum Samples or Maximum Time.