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View Full Version : Nd filter for Samyang 12mm and fuji X-E2



Morgo
18-02-2015, 7:09pm
Hi everyone, I'm hoping someone can recommend a 6 Stop ND filter for a Fuji X-E2 with the Samyang 12mm lens. I plan on getting my mate one for his upcoming birthday. Looking for a good quality filter around $80-130 prefer circular screw on to a filter system. I was looking at B&W but I'm worried they may be too thick to work with the 12mm even though its 12mm + crop sensor.

arthurking83
18-02-2015, 9:26pm
Just had a look at this lens.
I'm assuming the lens is the 12/2 for mirrorless cameras too yeah? .. if so:

When you refer to thickness, do you mean the filter glass(which can have an impact on the image) .. or do you mean the filter ring?

Again, I can only assume that you mean the filter ring, so if this is THE concern, I'd definitely go for a slim ring type.
I don't know if B&W make them, but Hoya do, and they're usually very good quality.
But I will make a prediction tho!
Looking at this lens and judging from my experience with the Sigma 10-20mm lens I have, I'd say that a std filter ring type may work fine too with no vignetting(if this is the worry).
Reason is that you don't take just the FOV of the lens into account and the size of the filter threads, but also the size of the front lens element in relation to the filter threads on the lens, and their depths.

I've briefly tried this with a Tokina 11-16 some years ago too:
On the Sigma 10-20mm f/4-5.6 lens, the font lens element is quite small when compared to the filter threads on the lens barrel. But, the bulbuousness of the front element was quite severe.
The protrusion of the front element of the Sigma lens is such that a straight edge across the filter threads, shows only a couple of mm of clearance.
With the normal centre pinch lens cap, this was no problem, but with one aftermarket centre pinch lens cap, I think the lens cap's insides actually rubbed on the lens.
That is the front lens element stood out more so than the Tokina lens's front element.
The Tokina on the other hand had a much larger front element.
As a rough example, if the sigma's front element was (say) 50% of the filter ring thread size(ie. about 40-ishmm in diameter), the Tokina was more like 75% of the size of the front threads(ie about 60mm).
The lens collects light from the outer edge of the front lens element.

Nett effect was that a standard type screw on filter on the Sigma lens caused no vignetting, it caused a little bit of vignetting on the Tokina(they both used 77mm filter threads).
So even tho the tokina lens has a narrower FOV than the Sigma(11mm vs 10mm), the relative differences in the lenses front element diameter compared to the thread size made the slight difference.
Note that the vignetting with this filter wasn't hard mechanical vignetting .. just the usual darkening.

Also not that I think it may have actually been caused by the filter glass itself, in that the filter was a CPL .. not so much the filter ring thickness.(FWIW, the CPL was set to the same orientation of unpolarised for both lenses).

So following that, glass thickness can impact on the image too. So if you question is about the thickness of the glass ...

The quoted FOV for this lens is 98° which is just shy of Sigma's 10-20mm lenses for APS-C, which is 102°.

I've used filters with my Sigma 10-20mm for years, and whilst they've been predominantly grads, the effect may be roughly the same(if you see it).

At the very edges of the frame with the grad, you may see reddening of very strong light sources in some situations.

I've see this with both the Cokins I used mainly, but than also with the Lees I got later too.
A condition I used to notice this more than other conditions, was on a cloudy(ish) day with the sun peeking through the clouds.
I used to use the clouds to lessen the harshness of the sun by waiting unto the sun was covered .. but the light through the clouds was still strong(remember, broken clouds not totally overcast).

The reddening was mainly on the clouds, and this usually only happened when the sun was at the edges of the frame(say the last 1/3rd or 1/4 of the frame.

The most plausible answer given as to why this happens sometimes is that when you think of what an ND filter actually does .. slow down light! .. it then makes sense.
In effect the oblique angle that the strong light is hitting the filter at causes the reddening .. one person once described it as a psuedo IR pass filter.

You're going to get this effect sometimes no matter what 'thickness' of glass filter you get.

Hopefully that answers the question in one way or another.

Morgo
19-02-2015, 8:05pm
Thanks, I ended up ordering a B&W 6 stop ND after I did some more reading and reviews on the lens with people commenting that due to the size and design standard filters are fine (as in they won't be seen)