Variable ND Filters

Discussion in 'Sony Alpha E-Mount Lenses' started by scott0487, Mar 2, 2015.

  1. scott0487

    scott0487 TalkEmount Regular

    Jan 9, 2015
    Is anyone using a variable ND filter, for example on a Sony 16-70mm? If so, any recommendations or bad experiences?

  2. robbie36

    robbie36 TalkEmount Veteran

    Nov 21, 2014
    I have had a variable ND filter in the past. I didnt really like it.

    You typically need an ND filter for 2 reasons. Because you want to shoot wide open in the bright sunshine and also perhaps to give a silky sea/waterfall effect.

    I very much doubt you would need it for the first instance with a zoom lens at f4 (depending on your camera). I am pretty sure iso50/1/8000th of a second on my A7 would have me covered even at f1.8 (and I live in Thailand).

    So the problem with a variable ND filter for silky seas/waterfalls, is that it invariably isnt strong enough. My variable ND claimed 1-8 stops ND but it maxed out at 6 (and this is quite typical from what I have read of variable NDs). Really for waterfalls/seas you need 10 stops. Of course 10 stops might be too much or too little if you are shooting at f8 iso100. But you can easily add stops or reduce stops by going to iso50-200 or f5.6 to f16.
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  3. Dirtistasty2

    Dirtistasty2 TalkEmount Regular

    Apr 10, 2015
    Don't do it. I've tried one and it makes images soft
  4. Bimjo

    Bimjo Super Moderator

    Oct 28, 2011
    Washington State
    Real Name:
    Variable NDs work better at longer focal lengths than shorter ones. On most wide angle lenses at full strength you'll get a big gray "X" across the pic. And cost doesn't seem to make much difference in that regard. My Singh-Ray (probably the most expensive Vari-ND filter on the planet) does it.

    Re: image quality- like with most filters, you get what you pay for. :)
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  5. NickCyprus

    NickCyprus Super Moderator

    Oct 11, 2012
    Real Name:
    Like Jim said, you definitely get what you pay for image quality wise...

    I only started shooting daytime LE. I originally wanted a variable ND too for the convenience but after long research I decided for the beginning to buy something cheaper to experiment (because I don't trust cheap variable NDs and good variable NDs are expensive). I got two cheap square type NDs (a 2-stop and a 3-stop that I combine to make a 5-stop) and it shows on the photos that they are cheap (soft, difficult to nail focus, color cast etc). However, another big issue I have is the difficulty of constantly removing and re-attaching the filters (remove to focus, attach to shoot - can be inconvenient when changing locations/angles). Now, I'm seriously thinking the vari ND route again (twist to min density to focus, focus, twist to desired density and shoot). Plus its easier to carry around (only one filter).

    And I've shot seascapes with just 5-stop ND with success so I don't think I need 10-stop ND. Its just a matter of available light.
    From what I've read the X-cross pattern appears when you use the vari ND at or beyond its max setting and for me a variable ND that is good until 7 stops is sufficient. The problem is that there are so many (did a search on B&H site) to choose from and prices vary. Reviews are also good on their cheaper variable NDs...
  6. xXx1

    xXx1 TalkEmount All-Pro

    Jan 15, 2013
    Major problem with variable ND filters is that they use a circular and linear polarizer to achieve their magic. Reflections are problem because they polarize light on their own and weird polarization is problem with wide angle lenses. That is, you may like them or not.
  7. Lisandra

    Lisandra TalkEmount Veteran

    Jan 28, 2015
    Bang for buck? Genus
    Performance/sharpness? Slr magic
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  8. Lisandra

    Lisandra TalkEmount Veteran

    Jan 28, 2015
    the slr magic is actually optimized for wide angle, so you dont get the dreaded x pattern
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