Filter size for Sigma 18-35: 77 or 82?

Hi.
For a Sigma 18-35/1.8 with MetabonesSB on Bmpcc. Obviously I will add a Hoya UV/IR cut, maybe I will need an extra filter like a black pro mist in future?


Sigma lens is 72 size, is 77mm fine or better to buy the 82mm? Genus tech Eclipse?
Thanks

I have an 82mm Genustech ND Fader and it fits the 18-35 as well as lenses with larger diameters when used with step up rings.
Unless size or weight is limited, larger is better in my opinion, especially for wide angle lenses.

On the Sigma 50-100/1.8 with Speedbooster can I use a 77mm filter stack?

Marco, I don't have those items to guarantee if the 77mm filter stack will suffice. I think so, but always good to buy some filters that are larger because one day you may have a larger diameter lens. Nice not to need to purchase larger filters then. Even if you might be fine, 82mm is a bit of future proofing. For example, my B+W 486 MRC IR Cut is 86mm since it's the first filter in my chain while the other filters are 82mm.


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thanks rick.

77mm threads are certainly a very common size but every once in a while there is a hot lens that requires 82mm, so the next time you fall victim to the ravages of lens p o r n you'll be better prepared.

By the way, if you use a step-up ring, brass rings, from Heliopan for example, are going to be easier in operations than metal rings as they shouldn't bind to your other metal pieces. Brass will cost more, but you can judge if you want to go with brass or the regular metal. In either case, don't screw on any filter until it's tight. But when stacking, sometimes an inner filter becomes tighter as you add outer filters!

Getting 'thin' screw-on filters if available is important as well when stacking filters to minimize the danger of vignetting.


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Yes i want to avoid buying filters for the third time...
I was thinking of 77mm because they are easy to find used on ebay.

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I'm planning to move from SLR magic 12+25+50 (i got 58mm filters to be small) to Sigma 18-35 + Speedbooster. Maybe a day also the 50-100 which would be a good complement.
Filters: Genustech Eclipse + Hoya Uv/ir cut. Would I need other filters? I read that sometimes its suggested a Black Pro Mist 1/8.

So 82mm its the best thing I suppose.

Some feel the Sigma 18-35mm is so sharp you can cut yourself with it, so a light filter may help take the edge off. I can't comment with authority , as I don't yet own those filters, but the Pro Mist or Hollywood Blackmagic are popular. I also like the look of a light Tiffen Glimmerglass. It can make your head spin looking at all the options but Tiffen is terrific with the comparative videos they produce highlighting their products. Even if you don't buy Tiffen, their videos are very instructive.

With filters, "less is more" meaning generally stay with lighter strengths such as ⅛ or ¼ unless you really want the filter to dominate the image. Other folks here can give you better advice than I can on those items that are ultimately subjective.

I've seen a picture of a filter case that contained perhaps a hundred different filters. Now that person knows filters!


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ok so to stay sure with vignetting with (three) filters, 82!
thanks rick

Rick is it right a price of 240$ for a 82mm Black Pro-Mist 1/8 ?

Marco, shouldn't be near that:


http://www.bhphotovideo.com/c/product/55692-REG


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thanks

By the way, with these type of filters, you don't want to screw it on as the first filter on the lens if you are using a variable ND filter. Put the variable ND on the lens first and the diffusion filter on top of that toward the light source.

http://www.bmcuser.com/showthread.php?1 ... gic-Filter



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I would go with 82mm, then you can handle most wide ange AOV lenses. I got 72mm filters for my Zeiss ZF lenses, which worked fine, but then I got the Veydra Mini Primes, and needed 77mm, now the 9.5 and 12mm Super Speeds need 82mm So, I should have started out getting 82mm, instead of buying three sets of filters -- dumb.
Cheers.

Certainly not dumb, but filters and lenses are areas where some future-proofing helps save in the long run.


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You are both right. Infact I'm waiting for my HoyaUV/IRCut and Genustech in 82mm size!