ND filters?

Discussion in 'Exposure Discussion' started by Robert, Dec 10, 2002.

  1. Robert

    Robert Member

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    Do neutral filters have any downside? Or are they miracles that can cut down the amount of light with no other effects? Maybe a dumb question but-))
     
  2. bmac

    bmac Member

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    Not a dumb question at all. I try to avoid putting any filter in front of my lens. You are going to experience some loss of sharpness unless you are using a top dollar filter. The real question is if you can even see the difference.
     
  3. swaitjd

    swaitjd Member

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    I have only starting using graduated ND's recently, but I have found them to be a great boon in situations where there is a "hot" sky and the horizon line is relatively flat. They've permitted me taking some images that would have been duds otherwise. I'm in Florida, so I find that situation rather easily! If I were in a mountainous terrain, I could easily see where the filters might not be so useful.

    Another consideration is that taking two images (one exposed for the shadows and another for the highlights) and merging them in Photoshop is a great alternative to ND filters, making the control of dynamic range completely general and not subject to such vagaries as the shape of the horizon line. It's also easier and quicker to apply in the field, though it does require more film. And some people just like to have the image on the film be the final one ...

    Joffre
     
  4. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Some are not absolutely neutral in color. The better ones like Heliopan and B+W are. Cokin ND filters may be have a warm tinge.

    With any glass filter, you are better off with a multicoated filter, but that's not an issue specific to ND filters.
     
  5. Robert

    Robert Member

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    How about the gel filters? It looks like I could get a holder and a few gels for a very reasonable price and use them on the two lens without shutters. Will the colour shift matter for B&W?
     
  6. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    The color neutrality is virtually irrelevant for B&W.

    Most of my filters are 3x3" resin filters. It's not a bad system if you have a lot of lenses.
     
  7. Robert

    Robert Member

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    It's just for the two lens without shutters. Not to mention no filter threads. I think with a few filters I can manage to get 1-2second exposures no matter what the light. That's slow enough for me to just use the hat trick.
     
  8. bmac

    bmac Member

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    I have never liked gel or resin filters, they are too easy to scratch. I don't baby my gear, hell I am really rough on it, so I go with multi coated glass. No worries about color cast with B/W, it is too subtle to make a difference on print film anyway.

    Brian
     
  9. lee

    lee Member

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    with regards to gel filters, I use them. On my Deardorff I put them behind the lens. That way they are not scratched or blown off. I donated a #25 to the West Coast Gods when the wind blew it right out of my hand. I now use the #23 filter. I have a type of tape that is really a glue that I press on the back of the lens board and attach the filter with that. Works like a champ.

    lee
     
  10. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    I have a fair number of old lenses with no threads or weird sizes, so I often tape filters behind the lens with gaffer's tape. On a couple of lensboards, where the lenses don't protrude too far, I've epoxied 3x3" filter holders to the board, so I can also slip a square lenscap on when the lens is not in use. This is particularly handy for ultrawides, where even a step-up ring for an oversized filter on the front threads will cause vignetting.