Filter: Slim vs. non

[psychorobotape]

hi everyone, I'm interested in getting a dark red filter and was looking at B+W's 67mm 029. I have a question, one is listed at $49.95 (on B&H) and another one at $96 the only difference being that the expensive one is a "slim" version which to my understanding means that it just doesn't have threads on the outer face of the filter. Is it real twice as expensive b/c of this or am I missing something??? Or is my understanding of "slim" incorrect? (they're both multicoated etc).

 

[psychorobotape]

Ok I'm guessing that the actual glass is slimmer too. Is this to further reduce flare? is it supposed to be sharper?

 

[Roger Hicks]

'Slims' don't vignette (or are less likely to vignette) with ultra-wideangles.

 

[KenS]

[QUOTE Or is my understanding of "slim" incorrect? (they're both multicoated etc).[/QUOTE]

I believe the 'slim' mount is to reduce the chance vignetting when mounted on wide angle lenses.

Ken

 

[Bruce Osgood]

In 35mm format my 28mm lens vignette with the standard filters. I suspect the 'slim' version would not. The same standard filter on a 50mm lens does not have this problem.

I would say you are paying more for non-vignetting at wide angles.

 

[Nick Zentena]

Are the coatings the same? IIRC B&W makes two grades. The higher priced comes with fancier coatings.

 

[fschifano]

But remember, you can't place a lens hood on the filters without female threads. Lens hoods are important, especially with wide angle lenses. Given a choice between fancy coatings or a lens hood, I'll go for the lens hood every time. The lens hood will outperform AR coatings most of the time in suppressing flare. Whether or not the filter causes vignetting is dependent on the lens design. A wide angle lens with a deeply recessed front element is more likely to be partially obscured by anything stuck onto the front of it. I use the regular thickness filters on lenses all the way down to a 20mm f/3.5 AI Nikkor without vignetting.

 

[Roger Hicks]

But remember, you can't place a lens hood on the filters without female threads...

Without clamp-ons or external bayonets, anyway -- both of which I have used...

 

[psychorobotape]

wow, 100% markup seems like a lot to pay for less threading but I guess If your having problems w/ vignetting then you don't have much of a choice huh... I'll be getting a mamiya 1000s w/ 80mm f1.9 in the mail here pretty soon, has anybody run into problems w/ vignetting on this lens with two filters on at once (say a polarizer and a contrast filter?

 

[fschifano]

Roger,
You're right about the clamp on types. I have a couple of them myself. Very handy items. Didn't think about them as I wrote.