You asked
Is the voigtl nder heliar hyper wide 10mm f 5 6 aspherical worth it?
Worth it if you want a very wide view and don't mind doing everything by hand. This is a manual-focus, non-stabilised prime, so you'll focus yourself. At 10mm on full frame it's wider than the 14-24mm range in the focal length guide, which suits big interiors and dramatic landscapes. f/5.6 is modest, so it's a daylight lens rather than a low-light one. On a Sony APS-C body it frames like 15mm, which is still wide but less extreme. If you shoot mostly in low light or want autofocus, look elsewhere. For a sense of where full frame pays off, see sensor sizes.
Written by Claude from this site's pages.