Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,566   Posts: 1,545,395   Online: 1087
      
Results 1 to 8 of 8
  1. #1

    Join Date
    Mar 2010
    Shooter
    Medium Format
    Posts
    3

    About ND and Polarizer filters

    Hello, I am from Uruguay, and I am new in this forum. I would like to know if somebody can explain if two polarizer filters can be used instead of Neutral Density filters to extend exposure time. Thank you

  2. #2
    Rudeofus's Avatar
    Join Date
    Aug 2009
    Shooter
    Medium Format
    Posts
    1,653
    Images
    10
    Yes, this can be done. If you do it with regular polarizer, watch out for slight color casts.

  3. #3

    Join Date
    Sep 2002
    Location
    Oregon and Austria
    Shooter
    4x5 Format
    Posts
    836
    Rudeofus,

    Great reply: succinct and informative.

    At the risk of seeming wordy in contrast, I'll still comment...

    When using two polarizers stacked, you change the amount of light transmission by turning. The problem is, when compared to ND filters, that there is no standard filter factor. You must meter through the filters in the exact orientation you will be using them. This is no problem with TTL meters, but if you're using a handheld meter, you need to make sure the polarizers end up on the camera lens correctly. Use the dot or printing to make sure they are oriented correctly. Also, when metering make sure that no stray light gets into the meter or you may end up underexposing. This is no problem with spotmeters, but with wider angle reflected light meters and incident meters, it can be tricky.

    If you're shooting color, you may have to add some cc filters to your mix. These will have to be determined by testing, since different polarizers behave differently.

    Best,

    Doremus Scudder
    www.DoremusScudder.com

  4. #4
    Mainecoonmaniac's Avatar
    Join Date
    Dec 2009
    Shooter
    Multi Format
    Posts
    2,995
    Images
    6
    You could make a variable ND filter with two polarizer filters stacked and changing the orientation of the filters to suit your density needs.

  5. #5

    Join Date
    Mar 2010
    Shooter
    Medium Format
    Posts
    3

    Polarizers instead of ND filters

    Hello Friends, thank you for your responses. I think that the problem with two polarizers is a degraded quality images due to so much glass... With ND filters this can be avoided, am I wright? Does anyone have some images taken with two polarizers? Thank you again

  6. #6

    Join Date
    Jul 2007
    Location
    Netherlands
    Shooter
    Medium Format
    Posts
    5,686
    You are quite right. Using a ND filter would be the better option.

    Polarizers are polarizers too, and will have more effect than just making the entire image look a bit darker. You may not like that.

  7. #7
    Rudeofus's Avatar
    Join Date
    Aug 2009
    Shooter
    Medium Format
    Posts
    1,653
    Images
    10
    Q.G., if you use a circular polarizer as the filter element closer to the subject, you should not have these problems. You have to hold it turned around, i.e. the side normally facing your lens should face the subject.

  8. #8

    Join Date
    Jul 2007
    Location
    Netherlands
    Shooter
    Medium Format
    Posts
    5,686
    That would work, yes.



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin