The lens, like virtually all lenses, is at its sharpest stopped down. This particular lens is notorious for reduced sharpness and contrast at f/1.4. It is certainly usable at that aperture if you can't get the shot any other way, but if you can stop down to f/2 or so you'll see a lot of IQ improvement. It is a very sharp lens at even smaller apertures.
This is a common complaint about the 1.4 - it really depends upon your expectations and your definition of 'actually sharp'. Not surprisingly, it is less sharp at 1.4 than it is at smaller apertures.
Here are some not very carefully made snapshots at 1.4 and 2.2 - while 1.4 is not nearly as sharp, I find that it is definitely usable, whereas many feel that it is not good enough.
at 1.4
Edited by pthompson on Mar 14, 2008 at 09:24 AM GMT
My favorite opening for this lens is 2.2. Thats the best opening for optical performance combined with nice DOF and bokeh! From 1.4 to 2.0 the micro contrast is visibly lower, and also you can still find some chromatic and spheric aberration. Use 1.4 if you have no alternative, it's still not really bad and for some subjects (portraits on a crop body) I find the full opening speed is still very useful. But from 2.2-11 this lens is as good as it can be, tons of EOSfun!
PetKal wrote:
Assuming you have not boosted sharpness/contrast on those images, yours seems to be a very good lens copy.
Others have suggested the same, but I have used three other copies of this lens with essentially the same results. Build quality being what it is (lousy) I wouldn't be surprised if there was a wide range of 'good copy, bad copy' with this lens, but I think there is also a large amount of misreading the extremely narrow DOF. Look at the sharpness fall-off from the center of the bottle to the edge in the 1.4 crop compared to the 2.2.....
I checked the EXIF, and these were shot RAW, converted with a medium contrast tone curve and a default sharpness of 25 (ACR) There was no other post, although I may well have downsized the jpeg with a bicubic sharper setting...I can't remember what was available in PS in 2005 when I took these shots...
My copy is comparable to pthompson's at f1.4. Taking people shots at that aperture is quite a challenge due to the narrow DOF. I tend to agree that this is part of the reason so many say this lens is soft wide open. I don't shoot wide open on this lens unless I have to, but I have taken some very nice shots with mine at f/1.4.
As long as we're talking about this lens, I read on here somewhere just today that the 50 1.4 does not report focus distance back to the camera. The context was relative to the 580 flash. Is this true?
_Rob_S_ wrote:
As long as we're talking about this lens, I read on here somewhere just today that the 50 1.4 does not report focus distance back to the camera. The context was relative to the 580 flash. Is this true?
Mine looks like the one above. (I consider the spice jar above "sharp" at both f-stops shown.)
Beyond AF miscalibration, which can happen with any lens, I've seen copies of the 50 that showed some halation at f/1.4, and another that showed severe orange fringe CA when new (actually my current copy). It was repaired by CPS and now works superbly.
This experience made me realize that the 50, when working properly, is one hell of a lens. I would expect that problematic samples of this lens that some have reported could probably be repaired, if their owners were aware of the possibility.
Build quality doesn't inspire confidence, but the EF 50/1.4 delivers. Sure, there are optical deficiencies (barrel distortion, awful bokeh, some longitudinal CA), but sharpness is present at full aperture. What is missing is high contrast: for that, you need to stop down. My interactive study...
