JT> Conclusion: Ths Sigma's poor performance wide open, along with its size JT> and weight, mean that it will not be part of my traveling kit.
I tested three specimen of the lens as well, and can only agree. The lens gets nice by 2.8 and quite better at 4-5.6, but from 1.8-2.8 it's unusable for large amounts of coma and veiling all over the image. Not mentioning the 2/3 stop light loss wide open even in the center of the frame. All this makes me think it's just a 2.8 design overstretched to 1.8, which is not a good thing. I am still considering the lens though, even tho I will probably not want to use it more open than 2.8 for the lack of performance. Best regards, Frantisek Vlcek
