The quality of the angle finder is canon typically very good. The workmanship is excellent - he looks very valuable from - no plastic fittings for the viewfinder - but what metal. The attachment to the camera is done simply and quickly.
The angle finder is very easy to rotate 360 degrees and locks at 45 degrees. It allows ground-level shots, where it is impossible to see directly through the viewfinder. But it also improves the convenience when shooting in a bottom portion that without him would be possible in principle, for example, a tripod while seated at not extended tripod legs - with Winkelsucher the neck muscles is considerably less stress.
The picture is very bright - I use it on a Canon 7D with a large bright viewfinder - and sharp. When switching between the 1.25 to 2.5 times the magnification you need to re-focus. This is partly negative feedback - if that were technically different solvable, I do not know. I use the angle finder to 90% in the 1.25 times magnification for taking pictures of animals lying down, therefore does not arise the problem of re-focusing on the rule. When I photograph sometimes ground-macros do I only fixed the shot with 1.25 times and place the focus then new to 2.5x one - with me it does not bother re-focusing.
It would be useful perhaps if you could fix the focus, as in ground-level shots you can get to the collar before and has a blurred image. I have the problem solved for me so that I the collar for wildlife photography - fix so no change from 1.25 to 2.5 times magnification, with an adhesive strip.
