OK. Let's play a game. Here are the contenders:
1) Canon EF USM 50mm f1.4
2) Super Takumar 50mm f1.4
3) SMC Takumar 50mm f1.4
4) Canon EF 50mm f1.8 (version 1 metal bayonet)
5) C/Y Zeiss Planar 50mm f1.4
6) Minolta Rokkor 58mm f1.2
7) Helios 44-2 58mm f2.0
8) Nikon 50mm f1.8 D
9) Nikon 50mm f1.4 AI-S
10) Zeiss Pancolor 50mm f1.8
I have shot 4 samples from each lens, each time MANUAL focusing from fresh using Liveview 10x mode. The Target is the crosshairs. THEY HAVE ALL BEEN SHOT WIDE OPEN. I have chosen the best one from each series, however they are fairly consistent among the samples. Some you will recognize easily. Others may surprise you. Granted of course that this unscientific test is probably victim of Lens Sample Variation (maybe I got a particularly good or bad version of this particular lens). The exposures are not perfect because I let the camera read it anyway that it chose. Same camera position, same framing. Some lenses let in far more light transmission than others for the same aperture value. Some lenses were completely unable to be sharp fully open. These images have not been color corrected or adjusted. Of course this doesn't tell the whole story about corner sharpness and what happens when we stop down a little. These are crops from the center, so this is just about trying to obtain optimal sharpness in what should technically be the sweetspot. You be the judge.
Can you tell which lens matches (Numbers) which target (Letters) ?
Which do you like best?
Which do you like the least?
Which is sharpest?
Which has the least Chromatic Aberration?
EDIT: I have stickied this because the conclusions (later in this thread) can be very helpful for newcomers on a budget who frequently ask what lenses they should be buying. Try and draw your own conclusions before seeing the results.