There was no bigger "cheat code" for my capturing of Radiance Fields than switching my lens to one better suited for capture. Let's take a look at some of the options, here. Please keep in mind that you will need to confirm your camera's compatibility with the lens.
Please keep in mind that fisheye lenses will not work for reconstructing Gaussian Splatting. However, I use a 14mm prime lens and that continues to work for Gaussian Splatting.
TTArtisan 7.5mm
Focal Length: 7.5mm fisheye
Camera Mount: Sony APS-C E Mount
Price: $
Why Choose It: This is probably the best bang for your buck if you have a Sony E-Mount APS-C camera. Make sure it's compatible though as it will not work with full frame E-Mount cameras. This lens is also manual focus only, but given the natural deep depth of field, that shouldn't be too large of an inconvenience provided you remember to check focus prior to shooting.
Rokinon 8mm
Focal Length: 8mm
Camera Mount: Sony E Mount
Price: $
Why Choose It: It's another affordable Rokinon lens! Like all the others thus far, it is manual focus only.
Rokinon 12mm
Focal Length: 7.5mm fisheye
Camera Mount: Sony E Mount
Price: $$
Why Choose It: A full frame alternative to those who want an affordable wide angle lens, but cannot use the TTArtisan. This lens is also manual focus only, so be sure to focus it prior to shooting. It's a solid durable lens with an aperture ring, though! Take a look at the following lens, too.
TTArtisan 11mm
Focal Length: 11mm fisheye
Camera Mount: Sony E Mount
Price: $$
Why Choose It: Just like the above Rokinon, it's another full frame E-Mount option. Its focal length is a bit narrower than the Rokinon, but it's still in the sweet spot range for lenses. You might be noticing a trend now that the more affordable lenses are manual focus only.
Rokinon 12mm
Focal Length: 12mm
Camera Mount: Canon EF Mount
Price: $
Why Choose It: A more affordable Canon EF Mount option, compared to the 14mm prime. The Rokinon is manual focus only.
Rokinon 14mm
Focal Length: 14mm
Camera Mount: Nikon F Mount
Price: $$$
Why Choose It: If you're a Nikon shooter and have been feeling left out from the list, this one is for you!
Fujifilm XF16mm
Focal Length: 16mm
Camera Mount: Fuji X Mount
Price: $$$
Why Choose It: Fuji has a slightly smaller pool of lens options compared to Sony and Canon. However, this 16mm prime lens is great, albeit a bit more expensive than some of the other options.
Fuji XF 8-16mm
Focal Length: 8-16mm
Camera Mount: Fuji X Mount
Price: $$$$
Why Choose It: This gets you a bit wider of a focal range compared to the 16mm prime. Coming in at a little more expensive, I'm not sure I would go with this lens, unless you plan to use the other focal lengths. It is a little nicer that you can get a bit wider field of view.
Canon 14mm
Focal Length: 14mm
Camera Mount: Canon EF Mount
Price: $$$$
Why Choose It: This is the lens that I use for my captures and it has made a massive difference in the success rate. It is pricy, but it's a sharp piece of glass that I go everywhere with. If you are in the Canon EF Mount ecosystem, there won't be a better lens to use.
Canon RF 14-35mm
Focal Length: 14-35mm
Camera Mount: Canon RF Mount
Price: $$$
Why Choose It: Canon unfortunately does not have a 14mm prime lens for the newish RF line. If you have a Canon RF mirrorless camera, this will be the next best thing. Though you'll want to stay at the wider end for your captures.
Sony FE 14mm F1.8 GM
Focal Length: 14mm
Camera Mount: Sony E Mount
Price: $$$$
Why Choose It: This is the Sony equivalent to the above Canon EF prime. It's a fantastic lens, though it comes at a steeper price. The f1.8 addition is nice, but you probably won't be opening your aperture that wide. If you're an E-Mount user, this will be the highest quality lens.