Im a big fan of Samyang lenses excellent construction and very sharp images. I’ve owned both the 14mm 2.8 ultra wide angle and the 12mm 2.8 fisheye which Ive used extensively on a full frame NikonD800 and then also the crop sensor Samyang 8mm 2.8 fisheye.
The 14mm 2.8 is one of the best options for astro photography and even when I also had the Nikkor 14-24mm 2.8 I tended to use the Samyang14mm more as its far lighter and smaller, image quality is negligible. The Nikkor 14-24mm lets in a bit more light for astrophotography as a 30 second photo at 2.8 on the Samyang lens I could achieve similar exposure at 25 seconds on the Nikkor 14-24mm at 2.8.
Now that Samyang have started rolling out their 14mm and 50mm prime lenses in auto focus for the Sony FE full frame. I’ve always been a manual focus shooter and as my photography tends to be more landscape I generally shoot with my focus set to infinity. But as the SonyA7R cameras have a really good auto focus it does make sense to use that.
The Voigtlander 15mm super wide is a fantastic lens to look at and no-doubt performs like a trooper when matched with a film SLR but is not so great when paired with a SonyA7R. Due to the lens being so close to the sensor even when using an adaptor to E mount it produces a very strong green at the edges.
The first problem I found was with an E mount adaptor the lens did not screw on without being slightly offset. This caused a problem in the small attached hood of the lens was in the frame when I took a photo, I thought a way to get around this would be to use a small rubber circular washer so I could align the lens correctly. That worked great but the extra couple of millimetres travel sent the focus off on the lens. So even when set to infinity pictures where very soft.
It is a fantastic looking lens and would have made a great point and shoot everything when set to infinity. But unfortunately not suitable with the SonyA7R.
This is the first version of the lens and would be ideal because of its price, I paid just over £200. You can get the version 2 and version 3 of this lens and they would work better on the little Sonys but the price is much more, so your defeating the object of getting a super wide lens for you Sony on a cheap budget.
So, instead of the Voigtlander if your after a super wide lens that works 100% for your mirrorless full frame Sony and you want a reasonable price I would choose the Samyang14mm and the Samyang 12mm fish eye. Both great lenses that I’ve owned and produce sharp photos.