Switch to English Language Passer en langue franšaise Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 75,239   Posts: 1,660,089   Online: 883
      
Page 3 of 3 FirstFirst 123
Results 21 to 24 of 24
  1. #21

    Join Date
    Mar 2011
    Shooter
    35mm
    Posts
    15

    additional info about anamoly

    As I mentioned before, a strange almost kirilian-like form appears in one image but not the other. Both are photographed at the same time, of the same event, with the same focal length lens AND both are on Tri-X emulsion. I don't want to post the image but if you would like to see it, send me your email address and I will send you the images. My email is vceinc (at) aol (dot) com.

    One is a 4x5 sheet film whereas the other is a 4x5 glass plate but both are considered Tri-X. My question is whether there are other differences between the two Tri-X films beside the fact that one is on glass and the other is on film. For instance, is there more gelatin on the emulsion of the glass plate? This would possibly absorb the UV more than the film if true. What are the halation differences between a glass plate and a film plate?

  2. #22
    AgX
    AgX is offline

    Join Date
    Apr 2007
    Location
    Germany
    Shooter
    Multi Format
    Posts
    9,861
    Glass plates due to their thickness (would) have much more pronounced (larger) halos.

  3. #23

    Join Date
    Mar 2011
    Shooter
    35mm
    Posts
    15
    I've studied this a little more now. I was wrong about the stock. I believe the camera and or lens itself is responsible for the kirilian-type of anomoly. I still believe the the kirilian-type of effect is in the UV spectrum (its not true kirilian because that isn't imaged through a camera lens, its a contact effect). The issue I believe now relates to the camera, lens or something there about. The explosion creates this effect in UV, but most cameras see the UV as a very soft blur around the explosion. This camera, however, sees this effect as a sharp artifact, not a blur, even when the explosion is sharp, there is usually a soft blur around the explosion from other cameras, i.e. the UV doesn't focus under normal circumstances. The only thing I can think of is that the optical system or Artar lens it uses must have a quartz component in some way which, I've heard, allows the UV to be imaged better, sharper UV image vs. soft blur. Is this possible? Its a 480mm Artar lens with an exposure around 4-5 micro seconds (optical shutter, not mechanical). This optical shutter consists of a piece of "flint glass" which polarizes with a charge and can make an exposure in this range.

Page 3 of 3 FirstFirst 123


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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