Saw this a bit late but hope you havent bought yet! If you want the most reliable setup for your doc, you absolutely have to go with the Sony E PZ 10-20mm f/4 G. It is seriously amazing! I know f4 sounds a bit slow, but honestly, the FX30 is so clean at its 2500 base ISO that it really doesnt matter for indoor stuff. Im always a bit cautious about using non-native lenses like the Sigma because you just cant beat native glass for the best autofocus tracking. It is so snappy and rock solid! Plus, the power zoom is fantastic for those slow, professional-looking creeps. Being able to go all the way to 10mm in a tiny basement is gonna be a total lifesaver! You are gonna love it!

Late to the party but unfortunately native Sony glass is getting way too expensive. I was disappointed with f4 lenses in dim studios before, its just not as good as expected. If you want to save cash, grab the Viltrox 13mm f/1.4 STM AF. Its fast and way cheaper than the name brands. Just watch out for focus breathing, but for a budget build its a solid choice.

Ugh that 1.5x crop is literally the worst part of the FX30 when you are stuck in a tiny room. I feel your pain... I have been there and it is so frustrating trying to literally press yourself against a wall just to get someone in the frame. It is just so annoying when the gear makes the space feel even smaller than it is. I have been really happy with these for my own stuff tho:

• Tamron 11-20mm f2.8 Di III-A RXD
• It is super solid and the f2.8 is basically mandatory for basement lighting. No complaints about reliability or autofocus speed at all.
• Tokina atx-m 11-18mm f2.8 E
• This one works well too. It is a bit more affordable and feels very sturdy in the hand. Tbh I would go with a constant f2.8 zoom over the f4 every time for indoor docs.

The Sony E 11mm f1.8 is definitely the lens you need for this project! I have spent a ton of time shooting with it on my own FX30 and it is just fantastic for exactly the scenario you're describing. When you're working in a tight Portland basement, that 1.5x crop turns your 24mm into a 36mm which is way too narrow for those wide environmental shots. The 11mm brings you back to a 16.5mm equivalent, which is wide enough to capture the whole studio while keeping the subject looking natural. The reason I suggest the prime over the zoom options is mostly about the light gathering capability and the physical size. At f1.8, you are getting way more light than the Sony E 10-20mm f/4 PZ G. That extra light is critical because you dont want to be cranking your ISO to noisy levels in a dark studio environment. While the Sigma 10-18mm f2.8 DC DN Contemporary offers more flexibility, I honestly find that native Sony glass handles the active stabilization and autofocus breathing compensation much better on the FX30 body. The 11mm prime is incredibly sharp and the focus is insanely fast. You will love how it feels on the camera... it is so small and keeps the whole rig really balanced! Go for the prime and you wont regret it.