17-40mm question

[HiFiGuy1]

Bryan'sreview of the 25mm II extension tube does say that it should only be used with lenses of 50mm+. I wonder if it would work at all with a 17-40 or if it would vignette too badly.

[Anthony]

To Daniel:


Thats a great picture, thanks.





To HiFiGuy1:


I thought of that too, but he also mentioned the magnification with the 25mm tube on the 17-40 review (1.02x).

[Bryan Carnathan]

If I recall correctly, Canon recommended that the 25 not be used on lenses wider than 50mm and Canon provided the 17-40 + 25mm ET spec. That would be a good test to run some day.