The best way to get a great looking image not withstanding lights and texture
manipulations is to render the image at the highest degree of resolution that
your system can handle. If you render at 3000×3000, you will be getting 300dpi
at 10"x10" hardcopy. From there you should find a service that uses MRI imaging
technique which can take your 300dpi image and increase the resolution to up to
1200dpi and shazam! You have a photo quality image that will knock your socks
off. Hope this helps.