When the package arrived I did the same course and tested strapped to the camera. Was tested on a EOS 7D with tripod. Initially close to 1m. Excellent! Already at an aperture of 1.4 knackscharf with buttery-soft bokeh, really nice! But then came the disillusionment. With more than one meter distance 3 of 4 pictures were slightly out of focus. The blurry photos a slight Fronfokus was visible (about 2-3cm). But not much at f 1.4, unfortunately, too much. Only from Aperture 4 or higher reliable results were possible. From 2-3m distance 100% Committee. Pictures completely mushy in the focused area. Beyond redemption, even with diaphragm 4 or 8.
What really would be possible is easy to check if you use Live View. Here the camera focuses on the sensor. Although significantly slower but she meets almost always! The sharpness is not comparable! Is it therefore the AF of the camera? No! My other lenses (EF 100mm F2.8 L IS Macro / EF 24-105mm F4 L / Tokina 11-16mm F2.8) all work properly on the same camera.
Normally, I would say "Good riddance" and return it. The imaging performance at F1.4 and a short distance but me so sure that I want to try it again on the Sigma Service. Of course, only if a free adjustment to guarantee is possible. From best in conjunction with my camera. I will contact the service next week and then everything must bring your own past, because it is the same with me around the corner.
To buy the USB adapter for 40 and then to make myself here with the setting and testing CRAZY I see honestly do not a. The settings for 4 distance ranges are already too little since only the last one will take the problem area with my lens from my perspective. In this area, but a constant deterioration of the sharpness will be held at my copy. I doubt that I could correct the problem with a single setting for this area. One product in this price range has to be working in my view properly. Without compromises! Therefore, no shenanigans ....
Of course I'll miss this review nor an update and possibly describe my experience with the Sigma Service and the results of the adjustment. If the results turn out well I correct my review like upward. However, currently only remains me to forgive a star because the lens in its current state is not to be used simply and easily.
Update 8/10/2014:
Meanwhile, some time has passed. Instead of the lens for adjusting to send I decided for a replacement. After I received the new Obejktiv was again big disappointment. Again massive problems with the autofocus! Also, this lens was useless ex works. This time I decided myself an adjustment to perform using the optional USB dock. With the software SIGMA Optimization Pro can be, at this lens, adjust correction values for 4 different distance ranges front- and back focus. First, I have, ermittel the focussing errors from from tripod that entpreschenden and then groped me the best correction values. The accuracy of the AF from the tripod is 1.4 aperture approximately at 75% when the AF is corrected. To my mind, an acceptable value when you consider how little the depth of field at 1.4. At smaller apertures the improved course. Another interesting point is noticed is that the correction setting for the respective distance really engages only exactly at this distance range. As an example: A centimeter more or less may decide in extreme cases, if the lens to focus the value + or -40 adapts! A jump-shaped transition is definitely not a good solution! Here one would have least have access to a linear function between the transitions. Since the correction values are not very high with me but that does not fall into the soaked.
In addition to the test chart I could test the lens last week to attend a wedding. I have taken predominantly in Aperture range 1.4 - 2.2. The yield of sharp images is now moving to the adjustment in a good area.
I have decided the lens to keep. Through the auto-let the factory defects corrected very well and I now come to enjoy the excellent image quality of this optical system. I therefore values on my review of a star on 4 stars. A star I subtract due to poor alignment with the Sigma is delivered.
Despite the rocky start, I am glad that I have dared to make a second attempt. It was worth it in any case!
