Tamron 28-75/2.8 (and some more letters) is an excellent optic. Unfortunately it is not wide enough being used on my K-7 with its 1.5x crop factor. It seems to me that 24mm on the wide end would do the trick for the specific kind of shooting I am doing with zoom lenses. Recently an opportunity presented itself and I shelled out for Sigma 24-60/2.8 (and some more letters).
Handling and build
It is ever so slightly heavier than Tamron but built in a more solid way. No zoom creep whatsoever. Very solid feeling. It feels reliable.
The filter size is 77 mm which is big in my opinion, but it does not feel that big, probably because fully extended at 60 mm, it is not very long.
It rotates the other way than Pentax zooms and Tamron. That's inconvenient.
All in all, it fully deserves the EX markings that Sigma gives to its high end products.
Integration with the camera
It consistently underexposes on my K-7. However I am using both highlights and shadows dynamic range enhancement as a matter of course, so, no big deal here.
I had to dial some AF correction as per indication of its previous owner. Nothing serious, nothing dramatic. It focuses reasonably well.
Interestingly however, it does not report full lens name to the camera. My LightRoom 3.0 says it is "Sigma lens" which is in principle correct, but I much rather it were just a little bit more specific.
I was slightly apprehensive about potential "Sigma" color. Some say that Sigma color rendering is slightly washed out and slightly yellowish in tone. I did not find anything of the kind yet. In fact, I am happy about its color rendering qualities.
Out of focus rendering seems to be a bit more pleasant than that of Tamron. But I did not shoot enough with this lens to come to any sensible conclusion. So "seems" is really a keyword here.
Sharpness is a mixed bag really. I very rarely apply any sharpening beside the default of the raw converter. In fact, I found by experience that applying of global sharpening is not a good thing for delicate out of focus regions, so I am being extremely careful here. It seems at this moment that the images of this lens are not really soft or low contrast, but they kind of ask for a bit of sharpening. I usually do it by "clarity" control of LightRoom.
Fully open the images are fully usable but there is slight soft focus effect. Not much so as to proclaim that fully open the lens shouldn't be used. But enough for my camera to be willing to close the aperture even at the price of increasing the ISO, which is a bit unusual. Closed down even the tiniest bit (even to f/3.2) it tightens up very nicely and becomes properly sharp.
Below are a number of shots I made with it as a matter of casual testing. They are slightly processed in a way I would normally process my shots, nothing out of the ordinary. And being test shots I included the focal length and exposure information as well.
In the LightRoom
LightRoom 3.0 came with the set of correction profiles for great many lenses, including those of Sigma. But this one despite being well known, popular and unfortunately discontinued hasn't found its way to the LightRoom data bases. A pity really.
I would surely keep shooting with this lens in order to better match to it. I will probably return and review this brief write up later when I gain more experience with this lens.
Stop Looking. Start Making.
1 week ago