SLR camera lens how to see the model to identify the quality
Canon red circle, Nikon gold circle, this is just outsiders to see.
Now out of the APS-C frame of the lens is no red circle, only full-frame lens has
For example, 17-55 lens, you can say less than the red circle of 17-40? But the former aperture is 2.8, the latter is 4, look to see it.
Fixed focus is the same, the same focal length, the greater the better aperture. 50 1.2 and 85 1.2 are better than 50 1.8 and 85 1.8. But 85 1.8 better than 50 1.8, this will have to see the experience. Of course, you are determined according to the price is right, but a lot of the lens you get the hands do not know the price, then see the aperture is no problem.
The easiest way
Aperture - the general aperture is a good head, such as the zoom head in the 2.8 aperture better than 4. The same L-level red circle, what to distinguish.
