Post by belgiumreporter on Nov 28, 2019 7:25:26 GMT -5
When i was testing some lenses it occured to me that not all leses have the focal lenght they are advertised at.
Now in zoom lenses there's the issue of "focus breathing" wich means the lens hasn't got the same focal lenght when focussed at a diffrent distance.
The sigma DC 18-250mm 1.35-6.3Macro HSM OS really falls short when close focussing as then it is nowhere near the 250mm it is sold for. At infinity it's OK and indeed gives a 250mm field of view, so focus breathing is clearly the issue here.
Another story is the sigma 120-300 2.8 wich dosn't give a 300mm field of view at ANY distance. This is a very expensive lens wich could give you a surprice when you would think getting the 300 at the long end...
Here's some (none cropped)shots from the test:
Now in zoom lenses there's the issue of "focus breathing" wich means the lens hasn't got the same focal lenght when focussed at a diffrent distance.
The sigma DC 18-250mm 1.35-6.3Macro HSM OS really falls short when close focussing as then it is nowhere near the 250mm it is sold for. At infinity it's OK and indeed gives a 250mm field of view, so focus breathing is clearly the issue here.
Another story is the sigma 120-300 2.8 wich dosn't give a 300mm field of view at ANY distance. This is a very expensive lens wich could give you a surprice when you would think getting the 300 at the long end...
Here's some (none cropped)shots from the test:
