06-27-2012, 12:17 PM
[quote name='photonius' timestamp='1340796787' post='19194']
Also, some Canon filters (to complete sealing) for (older) longer lenses are apparently curved rather than flat. Why, if not important?[/quote]
I'm only aware of protection elements on the front of some great white lenses that are slightly curved. That was done to prevent the inverted image ghost that a flat element could give. But as far as I'm aware, these are built into the lens itself, and are not an after-market option. It is a part of the lens design.
Also, some Canon filters (to complete sealing) for (older) longer lenses are apparently curved rather than flat. Why, if not important?[/quote]
I'm only aware of protection elements on the front of some great white lenses that are slightly curved. That was done to prevent the inverted image ghost that a flat element could give. But as far as I'm aware, these are built into the lens itself, and are not an after-market option. It is a part of the lens design.
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.