Originally posted by aquashin I recently acquired a FA 50mm f1.4. I bought this lens so I can catch my hyperactive 2 year old in action - tried f2.8, will not do. Cosmetically and mechanically the lens does not seem to have any issue. I took about 200 photos so far with this lens, mostly indoors or low light conditions. The results are very disappointing. Very soft at wide aperture - up to f2.8 - even then the images still look flat, no color punch, plain bokeh, etc.
I read the reviews from others and it seems most people experience similar issues - soft until f2.8. I don't understand.... What good is 50mm f1.4 if you cannot use it indoors or in low light conditions.
Perhaps I'm missing something here? I played with different ISO settings and apertures but can't find a magic way to mate this lens with my K10D. Is there a trick or a particular setting that makes this lens work? My wife has me on very short leash these days so I cannot afford anything more expensive like DA 55mm.
You need a bounce flash.
You are trying to do with Depth of Field and ISO what only a lighting solution can do.
To stop action with sharp images you simply need more light. That is the sole solution.
I got a 360 flash, aim it at the ceiling, get a nice sharp aperture at 180/sec (usually f/4-5.6 which are ideal portraits settings), and have no regrets. This is indoors with any reasonable lens.
For a low-light f/1.4 - 2/8 sharp shot you really need a non-moving subject in constant or near-constant light. If you try and catch kid playing across lighting zones, no lens can help you.
ISO can marginally assist, but you lose DR and add noise. It also messes up DOF. I sometimes use the K-x for this, but much, much, much prefer the bounce flash.
Light, light, light.
P.S. I second getting a lens hood for the FA 50/1.4. A $10, 49mm rubber screw-in is very helpful. Not necessarily for indoor shots only, but it really helps control flare outdoors or with a nearby flash. It also adds front element protection (+ the UV filter).