Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

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William Allum

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Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 12:27 am

Hi guys,

I've not used Tiffen before, would anyone recommend them or anything else? These are above my price range really, but I would prefer to spend the money on something reliable / good. If there's anything cheaper, but still good, I'd be very interested.

This is what I'm looking at:

TIFFEN 72MM VARIABLE ND FILTER
TIFFEN 72MM POLARISER FILTER
TIFFEN 72MM UVP FILTER

I need a polariser as I will be shooting though a car window (for a short film), and need to manage reflections.
Would it be crazy to use all three at the same time.

I've used a thin twist-able filter before, and it got stuck to my lens. It was very hard to remove, almost impossible, so I'm slightly put off by that with these.

I'm intrigued by the pro-mist filters too, which 'strength' is the most useful for general use.

TIFFEN 82MM BLACK PRO-MIST 1/4
TIFFEN 82MM BLACK PRO-MIST 1/2

I'm using the below speed-booster with the lens/camera:

METABONES NIKON G TO MFT SB ULTRA

Many thanks.
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Brad Hurley

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 12:38 am

Another diffusion filter to consider for this lens (aside from the Pro Mist) is the Hollywood Black Magic filter by Schneider, in the 1/4 strength. The Sigma 18-35 can have a harsh, contrasty look and is too sharp for some people's taste; the diffusion filter softens it. See for example the discussion at http://www.bmcuser.com/showthread.php?2 ... -diffusion

If you want a variable ND filter, you could also consider the one from SLR Magic, which comes in 77mm and does a good job of avoiding the usual issues with variable NDs.

One trick to keep your screw-in filters from locking onto the lens is to never screw them all the way in. Leave them a little loose so they're easy to remove.
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William Allum

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 1:03 pm

Hi Brad, thanks for the reply. Great, I will have a look at those.

I'd like to keep to 72mm, just to keep things simple if possible.

That's a good tip about screwing the filters on, I'll have to remember that next time. I wonder if there are any gadgets that can help get a grip, would be very interested in something like that, the rim is so thin otherwise.
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Brad Hurley

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 1:17 pm

FYI, I didn't answer your question about stacking filters as there are others here much more knowledgeable about that, but a few points:

1. The IR cut filter should be closest to the sensor, so put that one on first (based on everything I've read).
2. Variable ND filters are actually a combination of two polarizers...you might want to experiment with just the VND first to see if a separate polarizer is needed for your glare situation.
3. The diffusion filter, if you use it, should be the last filter in the stack (farthest from the sensor).

Stacking filters can degrade the image, so in general the fewer filters you stack the better.
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rick.lang

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Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 1:20 pm

Sticking to 72mm threads may be a mistake if you’re starting to build up a set of filters. I built up 82mm filters for my SLR Magic APO primes with a few 86mm filters as appropriate to augment those or fit the Tokina Cinema ATX 11-20mm.

It’s inexpensive to use them in smaller lenses, but you won’t need to repurchase filters in a year or two when you add larger lenses.


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John Richard

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 2:56 pm

And the larger filters help avoid vignetting on wider lenses. Step-down rings make it possible to mount larger filters onto smaller lenses.
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William Allum

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 5:17 pm

Amazing, thanks so much guys, really helpful.

Good to know the best order for filters, and going for a larger size of filter but using a step-down ring makes a lot of sense. It also seems like it might eliminate my problem with the filter getting stuck to the lens, a step-down ring should be easier to remove.
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Dune00z

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 5:52 pm

William Allum wrote:Amazing, thanks so much guys, really helpful.

Good to know the best order for filters, and going for a larger size of filter but using a step-down ring makes a lot of sense. It also seems like it might eliminate my problem with the filter getting stuck to the lens, a step-down ring should be easier to remove.


That is true but if you want to use that same filter on different lenses that have a different filter ring size, its not so fun. It can still seize with especially the anodized aluminum Sensei step rings. I have been using Breakthrough rings and they are by far and away the best step rings I have used. They are pricey, but ZERO seizes on my filters or lenses since using them. They are well worth the price.
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rick.lang

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 7:14 pm

I don’t have Breakthrough rings, but I have brass rings. The brass doesn’t bind as readily with the metal used in lenses and filters. Like materials attract so tend to fuse in place; unlike metals will not. Best advice regardless is not to tighten filters but leave at least a half turn of play.

If you do seem to have a stuck filter or ring, the best way to loosen it is NOT to apply force. Where you put some pressure to grip it tighter to loosen it just causes it to bind more. A very gentle quick nudge with some outward pressure (as if you’re trying to nudge a plastic lid off a container by pulling slightly outward as you gently nudge it to unscrew will suffice usually. Less pressure is more effective.


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Mattias Kristiansson

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostWed Oct 16, 2019 10:36 pm

I disagree with Brad Hurley with regard to the placement of ND filter, at least if you have a reflective one like my Formatt Firecrest IRND filters. As they are so reflective, they should be the first filter the light hits, so the reflected light doesn't get reflected back towards the camera by a filter in front of it.

Mattias Kristiansson
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William Allum

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostThu Oct 17, 2019 1:23 pm

Thanks Dune00z and Rick. I could not find Breakthrough rings, but I did find these on CVP.

Polar Pro Step-Up Ring

Temped to try those.

Thanks Mattias, I guess I will have to have a play with the order, and see what works best.
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John Richard

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostThu Oct 17, 2019 1:33 pm

There are also some interesting magnetic attachment filters that could help prevent binding and are far quicker obviously than have to thread filters on and off. I have not tried them myself.

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rick.lang

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostThu Oct 17, 2019 8:21 pm

Idea totally stolen from Zume filters?


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William Allum

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostTue Nov 19, 2019 4:42 pm

rick.lang wrote:I don’t have Breakthrough rings, but I have brass rings. The brass doesn’t bind as readily with the metal used in lenses and filters. Like materials attract so tend to fuse in place; unlike metals will not. Best advice regardless is not to tighten filters but leave at least a half turn of play.

If you do seem to have a stuck filter or ring, the best way to loosen it is NOT to apply force. Where you put some pressure to grip it tighter to loosen it just causes it to bind more. A very gentle quick nudge with some outward pressure (as if you’re trying to nudge a plastic lid off a container by pulling slightly outward as you gently nudge it to unscrew will suffice usually. Less pressure is more effective.


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Rick, finally got a filter and it got stuck. Tried your tip above, and it worked like a charm. Thanks very much.
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rick.lang

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Re: Filters for Sigma 18-35mm f1.8 Art & BMPCC4K

PostTue Nov 19, 2019 6:49 pm

William, that’s great. I intentionally do not screw filters on all the way but when stacking two filters, it’s easy that one will bind so I have practiced doing this!
Rick Lang

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