Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,484   Posts: 1,571,258   Online: 1034
      
Results 1 to 5 of 5
  1. #1
    Mustafa Umut Sarac's Avatar
    Join Date
    Oct 2006
    Location
    İstanbul - Türkiye
    Shooter
    35mm RF
    Posts
    3,953
    Images
    108

    Detection of Dichroic Glass or Coating at Lens, Common Technology for Vintage Lenses

    My quest continues to understand and make it stand the technology of 30s to 70s European and American best lenses.

    In time , I thought high low aberration per lens element in an objective plays as an unsharp masking filter.

    Second idea came later ,

    - I have an Kodak Ektar 111mm f:1.5 Fluroride lens and when I look to my mother , it looks as someone claimed as kodachrome or leica look. All the skin looks like shiny polyurethane lacquer coated plastic , everything is round , flawless and relief like , all skin wrinkles are deeper and shadows are deeper.
    It makes a dry skin looks like oil coated. That strong effect.

    - I watched a bolex movie and swiss made yvar lens was UNBELIEVABLE. All the colors were so strong and elegant and skin looks like a inflated baloon , not less. The face corners , cheeks , nose end was 3 tone brighter and it looks like it was glowing.


    I learned that dichroic glasses and coatings cut some wavelenghts and saturates the image

    I thought that dichroic technology would be the responsiple of all above experiments.

    I want to learn what is the way of detection of dichroic glasses and coatings at a objective ? How they would relieve themselves ? What is the technology to detect and analysis them ?

    Umut
    Last edited by Mustafa Umut Sarac; 10-18-2013 at 05:03 AM. Click to view previous post history.

  2. #2
    Mustafa Umut Sarac's Avatar
    Join Date
    Oct 2006
    Location
    İstanbul - Türkiye
    Shooter
    35mm RF
    Posts
    3,953
    Images
    108
    My only idea is to find a calibrated light source and analysis the lens output to input . But I thought may be some colors activates the effect.
    I dont have an idea. Waiting your ideas. May be an spectrum analyzer is needed. Is it common at physics labs ? I can bring the lens to few university labs but after had an idea.

    Awaiting your ideas.
    Umut
    Last edited by Mustafa Umut Sarac; 10-18-2013 at 05:07 AM. Click to view previous post history.

  3. #3
    Mustafa Umut Sarac's Avatar
    Join Date
    Oct 2006
    Location
    İstanbul - Türkiye
    Shooter
    35mm RF
    Posts
    3,953
    Images
    108
    I saw the same effects at Elmar, Summitar and Summicron specific to day or night light source. Such an strong real effect on photographs.

    Umut

  4. #4
    AgX
    AgX is online now

    Join Date
    Apr 2007
    Location
    Germany
    Shooter
    Multi Format
    Posts
    8,945
    Get yourself a common incandescant lamp, a cheap taining spetrometer and watch that spectrum of that lamp with and without the lens in question.

  5. #5
    Mustafa Umut Sarac's Avatar
    Join Date
    Oct 2006
    Location
    İstanbul - Türkiye
    Shooter
    35mm RF
    Posts
    3,953
    Images
    108
    Very good idea but my concern would not the spectrometer find the elemental analysis of glass at this experiment. How an spectrometer only measure the light but not elemental analysis of metal glass combination ?



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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