Photography blog has another helpful review. This time about the Samyang 24mm f/1.4 ED AS UMC, an affordable lens with excellent optic properties, and with no AF nor electronic metering. However, this lens is a valid alternative if you are on a budget, having a price tag of $699, and are looking for a fast lens (f/1.4!) with very good optical quality and perfomance.
The Samyang 24mm f/1.4 ED AS UMC’s build quality is reassuringly good [...] makes an ideal partner to a full-frame like the Canon EOS 5D Mark III t[...]. Focusing manually is straight-forward thanks to the responsive focusing ring [...], with Live View mode proving essential for closer focusing distances. [...] video shooters will positively embrace the de-clicked aperture version of this lens.
Image quality is generally excellent. Chromatic aberrations are very well controlled, geometric distortion is impressively low for an ultrawide lens [...], and the coatings successfully prevent contrast loss attributable to flare. The only real optical issues are obvious corner shading at the maximum aperture, something that every full-frame shooter has to put up with especially when using wide angles, and a lack of sharpness wide-open at f/1.4 and stopped-down at f/22.
Amazon US has a kit with the lens, bundling an UV filter, a cleaning kit, a memory card storage wallet and more, for $699.95 (click here)