Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,979   Posts: 1,523,703   Online: 1137
      
Page 8 of 9 FirstFirst ... 23456789 LastLast
Results 71 to 80 of 86
  1. #71

    Join Date
    Apr 2005
    Location
    San Bernardino, CA
    Shooter
    8x10 Format
    Posts
    734
    I hope that you are getting rid of the mice in a humane ,non-lethal way.

  2. #72

    Join Date
    Dec 2012
    Location
    Kettering, UK
    Shooter
    Medium Format
    Posts
    20
    So, PE, what is the optimum dye colour for Panchromatic emulsions please, if you were aiming for a single dye solution? I guess every emulsion had a different blue?

    Russ

  3. #73
    kb3lms's Avatar
    Join Date
    Jun 2006
    Location
    Reading, PA USA
    Shooter
    35mm
    Posts
    689
    Images
    5
    I think I will have to put out a want-ad for a cat.
    All this has happened before, and all this will happen again.

  4. #74

    Join Date
    Apr 2005
    Location
    San Bernardino, CA
    Shooter
    8x10 Format
    Posts
    734
    Jason,
    I was not going to put this out until I had more data, But as long as you have asked PE the question , I will say this. An Ag/Br emulsion (with no I) containing SDA3057, is red. Addition of NH4I causes the emulsion to immediately turn to a lavender-blue. Of course, I determined this by pulling small samples and looking at them under white light. The containers of emulsion are always in the dark, or under IR light.

  5. #75

    Join Date
    Apr 2005
    Location
    San Bernardino, CA
    Shooter
    8x10 Format
    Posts
    734
    Question for PE,
    PE, I now have 2 sets of glass panels waiting for evaluation. Set 1 is a 50/50 blend of 2 emulsions containing SDA3057 . Emulsion 1 contains no Iodine and is red.Emulsion 2 is emulsion 1 plus Iodine and is lavender in color.
    Panel set 2 is Pure emulsion 2 ( contain I) (lavender) coated first. Then a second coat of pure emulsion 1 (no I) (red in color).
    Any predictions?

  6. #76
    kb3lms's Avatar
    Join Date
    Jun 2006
    Location
    Reading, PA USA
    Shooter
    35mm
    Posts
    689
    Images
    5
    Bill et al,

    That wasn't me that asked about the color, but I always wondered about that. Many b/w films you buy are that purple-blue color. The ortho emulsion I plan to coat later this week is an ammonia digest AgBrI, with the I at 3%. Erythrosine was added to the AgNO3/NH4 before precipitation as advised by Glafkides. So, from what you are saying I ought to expect the emulsion to be that b/w film purple-blue color?

    Poor weather is forecast for tomorrow so I will be in the darkroom setting up. I will probably mix some 2718. So this question comes up:

    LIGHT SENTIVITY

    Things I have read and the label on the dye bottle says the stains-all dye is sensitive to light. The bottle itself is opaque. When it says light sensitive, how sensitive are they talking about? Can I mix in room light (avoiding undue exposure) and just store in the dark or is this so sensitive I must work by safe light?

    And if safe light would have to be used I guess it would have to be blue?

    How is the SDA3057 mixed?

    Any guidance appreciated!

    -- Jason
    All this has happened before, and all this will happen again.

  7. #77
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    22,932
    Images
    65
    Quote Originally Posted by wildbillbugman View Post
    Question for PE,
    PE, I now have 2 sets of glass panels waiting for evaluation. Set 1 is a 50/50 blend of 2 emulsions containing SDA3057 . Emulsion 1 contains no Iodine and is red.Emulsion 2 is emulsion 1 plus Iodine and is lavender in color.
    Panel set 2 is Pure emulsion 2 ( contain I) (lavender) coated first. Then a second coat of pure emulsion 1 (no I) (red in color).
    Any predictions?
    Bill;

    Without a good wedge spectrogram it will be difficult to evaluate the results unless you use Wratten separation filters for R/G/B. So, lets just wait.

    The no Iodide emulsion may be too slow to register properly at the green wavelengths.

    PE

  8. #78
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    22,932
    Images
    65
    Quote Originally Posted by kb3lms View Post
    Bill et al,

    That wasn't me that asked about the color, but I always wondered about that. Many b/w films you buy are that purple-blue color. The ortho emulsion I plan to coat later this week is an ammonia digest AgBrI, with the I at 3%. Erythrosine was added to the AgNO3/NH4 before precipitation as advised by Glafkides. So, from what you are saying I ought to expect the emulsion to be that b/w film purple-blue color?

    Poor weather is forecast for tomorrow so I will be in the darkroom setting up. I will probably mix some 2718. So this question comes up:

    LIGHT SENTIVITY

    Things I have read and the label on the dye bottle says the stains-all dye is sensitive to light. The bottle itself is opaque. When it says light sensitive, how sensitive are they talking about? Can I mix in room light (avoiding undue exposure) and just store in the dark or is this so sensitive I must work by safe light?

    And if safe light would have to be used I guess it would have to be blue?

    How is the SDA3057 mixed?

    Any guidance appreciated!

    -- Jason

    Jason;

    For starters, please be careful with both heat and light! I refrigerate all of my dyes at 4C.

    Most all dyes can be handled for a short time in subdued tungsten light or a safelight.

    Best of luck.

    PE

  9. #79

    Join Date
    Apr 2005
    Location
    San Bernardino, CA
    Shooter
    8x10 Format
    Posts
    734
    Jason,
    If erythrosine is your only dye, the emulsion would be sensitive to blue and green only. Therefor a RED light is called for. You would never use a blue light with any Ag/Br emulsion, with or without I. All of these emulsions are sensitive to blue. I am not familiar with the Stain All dye. But if it is truly panchromatiic, I would use a cheap($150) "Night Vision" monocle with an IR light source. Barring this, I would use a red light pointed away from your work area and as faint as you can handle.
    SDA3057 - I mix a 1% solution in 100% methanol In a brown bottle and store it in the freezer. A dry dye in pure form should be able to withstand a brief exposure to light.
    Bill

  10. #80

    Join Date
    Apr 2005
    Location
    San Bernardino, CA
    Shooter
    8x10 Format
    Posts
    734
    PE I use glass RGB separation filters(custom and pricy) for both testing and "real*photography. I normally photograph a KODAK color chart under full spectrum artificial light to shoot my test plates. With no filter, then each RGB filter.
    Bill

Page 8 of 9 FirstFirst ... 23456789 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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