Nice piccy.
I reckon you may need to invest in a 10.5mm f/2.8 Nikon lens and /or a 4.5mm f/2.8 Sigma circular fisheye. These are two of my favorite lenses, great for full milky way shots.If you are near the city or eastern suburbs, you could borrow these lenses from me for a weekend.Generally, fixed focal length lenses are better due to less internal reflections and light falloff. Alas, Photokina has not unveiled any breakthrough technologies in photography.
Once curved sensors start being mass produced, it is time to chuck out all the old glass as fast lenses will be the norm, since a curved sensor means no more optical correction for flat field and spherical aberrations will be minimized.We should find the best performance to be at widest aperture. Look forward to f/0.95 lenses that do not cost a fortune or weigh a ton. I reckon that eventually such whole sky shots could be hand held or tripod jobs with cameras that use sensor shift for stabilization eg Pentax K-5.
If you can wait a few years, this sort of photo will be a mere snapshot instead of an impressive stitching job
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