Tommydigi wrote in post #13937542
Would you mind telling me what some of those idiosyncrasies are? The Singh-Ray Vari-N-Duo is what I was interested in.
thanks
I first tried the standard mount of the Vari-N-Duo, but the vignetting was a bit much (all the way up to 35mm focal length). I sent the filter back, and the folks at S-R converted it to the slim mount, which improved things quite a bit. It still vignettes, but not as severe (up to 24mm). I knew this going in before I bought the filter, so I don't see it as a major problem.
Variable filters will create a X-pattern when shooting at very wide focal lengths, depending on how much ND strength you have dialed. All variables do this...its simply the nature of the beast. With the S-R filter, the X-pattern will appear when I'm at max density or just beyond, and its completely gone by 35mm focal length. The knockoffs (Fader, Polaroid, others) will generally exhibit X-pattern much sooner, such as when only 5-stops of ND are dialed. There's also the IQ problems and color cast issues with some of the lower-tiered variable filters...lots of threads on these if you care to search the forum. As I mentioned, with the S-R filter the X-pattern is completely gone at 35mm and longer...can't speak to the knockoffs on this particular subject.
The S-R is a great filter, no obvious colorcast, and no adverse IQ problems...its what you'd expect from a high-quality filter. If you can deal with the idiosyncrasies (strength/focal length), its well worth the expense.