For some reason, I have a natural affinity of 35mm FoV lenses that can create nice, soft out of focus areas. I currently own a PanaLeica 15mm, and while it's a great lens and it can deliver the type of OoF areas I like, I have to work more in order to get the shot. It's a factor of the m43 sensor size, the wide FoV the lens offers, along with a moderate speed of f/1.7. I've recently started looking at what other options could give me what I'm looking for. Initially I thought of picking up a Sony A7II and a Canon FD 35mm f/2.0 (I already have some Canon FD lenses, more on that later). The camera would give me IBIS, and it would give me an equivalent of a 17.5 f/1.0 lens on m43. Additional benefits are the 3:2 aspect ratio sensor (for some reason, I crop a lot of my shots to 3:2, I guess that aspect ratio just looks better to me), IBIS for all lenses, and better dynamic range along with noise. But once I started looking at all of the costs associated with picking up some additional lenses and everything else, I started to second guess this option. Then, I thought about the Voigtlander f/0.95 lenses. They offer a 17.5 f/0.95, basically equivalent to the above mentioned option. I could get one used for around $600, FAR cheaper than the option of Sony A7II. I'm just not certain how it performs, and from what I've seen wide open it may be a bit soft. To fix that issue, I could stop it down a stop to f/1.4, but then I wonder how close that puts me in terms of what I'm able to get with the PL15 @ f/1.7 I already own. But then I thought of another option. Last summer I picked up an RJ Focal Reducer and some Canon FD primes (24f2, 50f1.4, 100f2) so that I had some fast, manual focus options for shooting videos with on my GH4, as I wasn't pleased with the focus-by-wire system in a lot of the native lenses, particularly when trying to do slow focus pulls. Once using the adapted lenses for videos, along with stills, I really enjoyed all that is involved with shooting manual focus lenses. It just so happens that when putting the 24mm f/2.0 on the focal reducer, it becomes a 17.5mm f/1.4 when shot wide open. I figured this would give me a good idea of how the Voigtlander would perform at f/1.4, at least in terms of DoF. Plus, I could see if this combo would be "good enough" for what I'm looking for. I took a series of shots from a tripod with both the 17.5 and PL15 lens options, at f/1.4, f/1.7, f/2.0, and f/2.8. I wanted to see just how big of a different the focal length makes in DoF, along with how much DoF control I could gain with a 17.5 f/1.4 lens over a 15 f/1.7 lens. The shots can be seen below. They were RAW files, worked in Exposure X for color and sharpening, and then exported to LR 6 for cropping. I attempted to crop each image to the same framing to give me an equal approximation, and resized each image to 1600 px wide. 17.5 f/1.4 17.5 f/1.7 15 f/1.7 17.5 f/2.0 15 f/2.0 17.5 f/2.8 15 f/2.8 When viewing the results from the 17.5mm combo, I don't really notice a difference between the f/1.4 and f/1.7 examples when it comes to DoF. What I do notice is the vignetting that is present when shooting wide open at f/1.4. I don't notice a real difference in sharpness until the lens gets to f/2.0, but I still think it's sharp enough when shooting at f/1.4 or f/1.7 based on how the image was sharpened. As for the 15mm, it's pretty sharp wide open (as is to be expected from a modern lens). It vignettes a bit wide open, just like the 17.5 did (I don't view this as an issue, I tend to like it as it's not too heavy). There also is a slight difference in DoF between f/1.7 and f/2.0, but not as noticeable when compared to the 17.5 at the same apertures. There is a noticeable difference once stopped down to f/2.8, just like with the 17.5. So, what did I learn from this? Well, I can definitely see the difference between the 17.5 @ f/1.4 and the 15mm @ f/1.7 (both lenses wide open). I do like the more shallow DoF that the 17.5 offers, although the difference isn't all that great when comparing both at f/1.7 (although I guess every bit counts). Questions I still have are, is the Voiglander as sharp wide open @ f/0.95 as the Canon 24mm is adapted and wide open @ f/1.4? If so, maybe the Voigtlander will be sharp enough for me. Also, the additional stop of difference between f/1 and f/1.4, if as noticeable as the difference between f/1.4 and f/2.0, will be a welcome addition. Now I'm just left to determine if the benefits the Sony A7II offer outweigh the cost difference (and also, how sharp is the Canon 35mm f/2 vs. the Voigtlander f/0.95 when shooting both wide open).