ND Filter Color Cast Testing

There's probably at least 10 different ND Filters around the studio, most of them being a type of 'Variable ND' or 'Fader Filter'. They are just so handy at getting the right exposure. Some of these filters use glass that will cast a purplish color, some more than others. Besides being able to confirm through reviewing your videos, here's another way we found. It's hard to see much difference by just holding it up to the light, and for some reason using the reflective surface from a Macbook works pretty well. As you can see two of the four don't have any color cast even when we played around and dialed them to different ND stops. The other two always have this color cast even when dialing them up or down.

Keep in mind that this does not solely apply to 'Variable' filters, but a color cast can appear in static ND filters too. For static ND filters, it would be very obvious and won't require you to flip them around. So I know you're wondering, which two had the color cast? Polaroid ND Filters and Nicna (sometimes called Rainbow Imaging). The Polaroid was actually the one with the most Purple color cast. Which ones did not have a dramatic color cast? Fader ND and Nature did not cast. Of course we all know you can't go wrong with the LightCraft Fader ND Filters, but for a slightly cheaper price I'm quite fond of the Nature brand Variable ND filters which you can find below.

fader-nd
find-price-button Nature Fader ND Variable Filter

41 thoughts on “ND Filter Color Cast Testing

  1. Emm

    Post author

    @Sam - They are variable NDs, and if you look at them sitting on the table, you can see about the same amount of light passing through each. Regardless of the density if you see purple visually with your eyes, it will show up in your image.

    This still doesn't account for loss of sharpness, so just because you have no color cast on an ND, there are other things to still test to verify if it is good.

  2. Sam

    Hi Emm. Just one question. Before you flipped over the variable ND filters to show the color casting, did you set the ND settings on all of them the same, eg all at ND8 or equivalent? I believe that would affected the outcome with the variable ND filters as we all know being two polarized filters stacked together. Regards Sam

  3. How I wish I had seen this test before buying the Polaroid. Sigh. Sure enough, I get an impressively violent violet across the middle of my shots.

    Although strangely not every time!

  4. Kjeldsted

    I've recived recently four varible ND filters from my boss, to test these filters.
    I did this test with my MacBook Pro, and it seem that one of these filters didn't pass the test. A very expencive Heliopan filter.
    So I am wondering if this test is usefull at all. I can't imagine that Heliopan would make a very crappy filter?

  5. Emm

    Post author

    @Deja - if you used an oversized filter, it probably won't have vignetting on a 12mm with a GH2.

  6. deja

    Hello, I want to buy Heliopan 77mm or 82mm, but I don't sure about vignetting with olympus 12mm f2 with gh2 (crop x2), may be somebody can help me?

  7. David

    So Emm, which fader ND brand were the purple ones, I'm thinking about getting the Nature brand. Was that one of the purple ones?

  8. Emm

    Post author

    @DamirK - It's two polarizers crossed. You'll probably notice it most when you stop down your aperture, and notice it less when your aperture is wide open.

  9. stats

    I have a number of nd filters: Tiffen, B+W, off-brands directly from China, and lightworks. All of these filters have a color cast. I'm tempted not to use nd at all, and just crank up the shutter for exposure comp. Yes, I know, you get the strobe effect, but haven't decided which is worse, the awful color cast or artificial looking crisp edges on moving objects. And despite what everyone says, it ain't necessarily that easy to get the color cast out in post. This is one of my biggest frustrations with dslrs.

  10. Dang man... I got a 46mm polaroid VariND because it was the only one in that size... didn't realize how purple it changes the video... I guess since I color correct in post, I didn't realize how much I've been having to compensate for it. Thanks for this. Gonna get a NATURE 77mm now for my canon.

  11. tr0

    I have gone through a lot of vari ND reviews, and decided I won't anything below Heliopan ND. It is supposed to have little to no color cast with great sharpness.

    I've also seen tests of LCW faders and it is terrible. I would prefer to use 1/1250 than this one...

  12. PixCanFly

    I have both LCW and Nature Vari ND. Even though they don't create color cast problem, they do soften and affect the picture quality. The Nature Vari ND is the worse of the two.

  13. alex

    I own the Fader ND, the LCWII ND and they BOTH really softened up the image way too much to be used seriously, at least in my opinion. They also both had a color cast, which I didn't like. I was using these on the 70-200 as mentioned above and it just made the shots worthless. I then invested (about $600 for the set) in two sets of Tiffen Water White NDs over a nine stop range. They are not vari/fader types but are the static single type. Much better results. FYI, B&H doesn't stock the right set of these (or has the wrong price on the set that they do stock). I had to buy from a place in Hollywood.

    Anyway, the point is that I tried two fairly good variable NDs and gave up on them. Shane Hurlbut came to the same conclusion and then designed these Water White NDs with Tiffen and I went with those. Much better. However, I still found a slight color cast on those, but at least it was either green or magenta cast, which is easy to take out in post. The brown cast from the Fader types were terrible. I'll sell both my vari NDs, but I live in Singapore and by the time shipping in included it would only make sense to sell them locally.

    Just my two cents of experience.

  14. Emm

    Post author

    @FJGPhoto - I agree, you can't ask too much from such tools. They already provide such a convenience with price + performance to dial down up to 9 stops. Static filters will be better than variables if you are trying to maintain sharpness at longer focal lengths.

  15. FJGPhoto

    I haven't seen one of these vari-ND filters that HASN'T been soft past 85. Even the Singh-Ray (though lesser so than others) and the Genus.

    BTW I also have one made by STPPO thats less expensive than the Nature and very similar in quality. Very little to no color cast. But as with almost all vari-ND filters...about 85mm is the max for sharpness on this one too.

    Honestly, the more you increase the ND strength on almost all ND filters (static included) there usually is some level of color cast. Ask any Hitech or Cokin static ND filter user.

  16. Emm,

    Definitely do a test with an 85mm and a 70-200 to test the sharpness of these filters. My LCWII is terribly soft past 85. You can really see it when you hit the 5x and 10x zoom feature before recording.

  17. Patrick P.

    Hi Emm,

    didn“t you purchase a Heliopan Fader ND too? Or am I mixing somethin up here? If yes, Id like to know how it performs color casting-wise. Thanks!

  18. Emm

    Post author

    @Michel - I've been trying to get to testing these fully, it's just been busy here. The Nature does not have dramatic softness like some others.

  19. Michel

    Emm, how about softness at larger focal lenght? I have the Lightworks, it still performs quite good at longer focal lenght, the cheaper ones are said to get very soft - did you get to check the Nature V-ND about this?

  20. ProductUV

    I am also looking for a Vari-ND filter of the Tokina 11-16mm. Last I heard the only filter to work without vignetting was the $390 Singh-Ray 77mm "Thin Mount". Does anyone know of a alternative to the Sighn-Ray ?

    Thanks All.......

  21. Emm

    Post author

    @MrDinaguan - The best filter would be the static ones (not variable). To compensate, you could change AV + ISO and still maintain same shutter speed. Not as convenient, but you could carry a basic set of ND2, ND4, ND6, and ND8 filters. These are also stackable if you really needed to.

  22. Emm

    Post author

    @steve - o - It shouldn't make much difference except for possible vignetting and being more prone to lens flares. I would check out some lens hoods that would fit that ND.

  23. steve-o

    Hi Emm - Greetings from Toronto! I'm working with a tight budget (as most of us do) and was wondering if it's advisable to just purchase a variable ND filter and just work on 2 step up rings (I have a 85mm 1.8canon, 50mm 1.8canon & 30mm 1.4 sigma)? Thinking of just getting the 62mm filter (for sigma lens) and just use 2 step up rings for the other 2, will it affect the quality?

    Please advice - thanks!

  24. Geoff

    I have yet to see an in depth review of tiffen's Vari -ND filters. I would think they would perform quite well.

  25. pm5tr

    @Emm I know, I guess it's the same with every fader ND, but can you confirm the Nature brand ND vignettes on the Tokina or not? Thanks!

  26. Emm

    Post author

    @Jarrod - I've been using a variety and haven't noticed a 'dramatic' color cast, but some are better than others.

  27. Emm

    Post author

    @pm5tr - The Mark II LCW has an oversized front filter to prevent vignetting. This also means you won't be able to use the standard hood.

  28. I have the polaroid ND filter and I have not noticed a dramatic cast in my footage? I'll have to do this test and see if I get the same results.

  29. pm5tr

    Hi emm!
    You should do a video between those on camera, to see the actual footage side by side maybe. I'm just planning on buying the lcw mkII. Does the nature brand vignette on the Tokina 11-16? I heard the lcw is slim enough for it.

  30. videoguy916

    Ahh I cringe at the sound of the filters scraping against the beautiful aluminum macbook. haha.

    Thanks for the info. Crazy how much the color can change.

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