I recently purchased a Singh-Ray Vari-ND Thin Mount but to my disappointment, it shows up at the corners at 24 mm (FX). Does anyone else have this problem? It is disappointing given that this is arguably the most expensive Vari-ND out there. Sample image attached.
Unfortunately, it doesn't matter what you pay, physics are physics, and when you get that wide, this can be a problem since the filter has to have some depth, and a Vari ND thin mount is still going to be thicker than a fixed stop ND thin mount. It's just thinner than the non-thin variant.
What lens were you shooting?
You might get away with using the next larger size filter and an adapter ring.
It's both, or neither. As Mick says, the wider the angle of view, the easier it is for things to get in the way. That's all there is to it. The only way for this not to occur is for the lens to be built physically differently. For example, if it were built as wide as the Lee Foundation filter holder - I think that's 95mm - then it yields far more unobstructed area in front of the glass elements. But at 77mm, there's only so much that can be done. Lest you think that it's something magical about the Lee, it's not. The very same item (and as you now it's quite expensive) vignettes horribly on ultra-wides such as the 14-24 and Sigma 12-24, leading to the Lee SW-150. What's different about the SW-150? Fundamentally it is using 150mm wide filters, rather than 100mm ones. Basically it has filters that are physically about twice as wide as your 77mm ones. Even the SW-150 vignettes horribly on some lenses. For example, it's pretty much hopeless on the Sigma 8/f3.5 and Sigma 4.5/f2.8 DX, since they are circular fisheyes that cover 180 degree field of view in all directions. There's close to no physical way for anyone to construct a filter to work on such a lens.
If you'd like to think of it as a lens issue, consider that the Sigma 24-70/f2.8 does NOT have the same problem at 24mm. That's because this lens is physically built larger, namely it takes 82mm filters...
_____ Brian... a bicoastal Nikonian and Team Member
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