Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,550   Posts: 1,544,705   Online: 941
      
Page 3 of 6 FirstFirst 123456 LastLast
Results 21 to 30 of 53
  1. #21
    David A. Goldfarb's Avatar
    Join Date
    Sep 2002
    Location
    Honolulu, Hawai'i
    Shooter
    Large Format
    Posts
    17,289
    Images
    20
    Quote Originally Posted by cahayapemburu View Post
    What does this developer do that a real developer couldn't do better?
    It can be made from stuff available at the grocery store.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com

  2. #22

    Join Date
    Nov 2007
    Shooter
    35mm
    Posts
    47
    Define "real developer": One in which the actual developing agent is identified and quantified, for starters, and one in which there are no ingredients that do not contribute to the working properties of the developer. If this developer is only distinguished by its over the counter ingredients, I don't see the point in commercial production.

  3. #23

    Join Date
    Mar 2004
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    3,879
    Images
    11
    Quote Originally Posted by cahayapemburu View Post
    Define "real developer": One in which the actual developing agent is identified and quantified, for starters, and one in which there are no ingredients that do not contribute to the working properties of the developer. If this developer is only distinguished by its over the counter ingredients, I don't see the point in commercial production.
    OK, Caffenol (aka Folgerol) meets all of the requirements of your definition.

    I see no point in the commercial production of Caffenol.

    Pyrocat-HD, Moersch Tannol, PMK,WD2D, 510-PYR0, Prescysol, DiXactol, etc. are examples of commercially available staining and tanning developers.
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

  4. #24

    Join Date
    Nov 2007
    Shooter
    35mm
    Posts
    47
    I don't think Caffenol meets my definition. What is the actual developing agent, how much of it is contained in a given quantity of coffee, and how do you know? What is the chemical composition of coffee, and how do its components contribute to the working properties of a developer made with it? If these things are known with any certainty, I've never seen a published description. I understand the novelty of making a working developer from household ingredients, but I also understand the limitations of that approach, and frankly don't understand the persistence of the attraction beyond its novelty. Any and all of the developers listed at the bottom of your message are more effective and more reliable, and most are published formulae. Just calling a spade a spade.

  5. #25

    Join Date
    Jun 2004
    Location
    Twin Cities, MN
    Shooter
    Large Format
    Posts
    164
    Images
    16
    Quote Originally Posted by cahayapemburu View Post
    I don't think Caffenol meets my definition. What is the actual developing agent, how much of it is contained in a given quantity of coffee, and how do you know? What is the chemical composition of coffee, and how do its components contribute to the working properties of a developer made with it? If these things are known with any certainty, I've never seen a published description. I understand the novelty of making a working developer from household ingredients, but I also understand the limitations of that approach, and frankly don't understand the persistence of the attraction beyond its novelty. Any and all of the developers listed at the bottom of your message are more effective and more reliable, and most are published formulae. Just calling a spade a spade.
    Have you read this? http://www.rit.edu/~andpph/text-coffee.html

  6. #26

    Join Date
    Mar 2004
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    3,879
    Images
    11

    Reducers in Caffenol are caffeic acid and ascorbic acid

    Quote Originally Posted by cahayapemburu View Post
    I don't think Caffenol meets my definition. What is the actual developing agent, how much of it is contained in a given quantity of coffee, and how do you know? What is the chemical composition of coffee, and how do its components contribute to the working properties of a developer made with it? If these things are known with any certainty, I've never seen a published description. I understand the novelty of making a working developer from household ingredients, but I also understand the limitations of that approach, and frankly don't understand the persistence of the attraction beyond its novelty. Any and all of the developers listed at the bottom of your message are more effective and more reliable, and most are published formulae. Just calling a spade a spade.
    I'm all in favor of calling a spade a spade.

    Some of the developers I listed are open literature published formulae - others are proprietary. "more effective and more reliable" depends on the application and the results obtained, IMHO.

    http://www.apug.org/forums/forum37/3...they-work.html


    http://silent1.home.netcom.com/Photo...tml#Caffenol_C

    http://www.apug.org/forums/forum37/3...they-work.html
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

  7. #27

    Join Date
    Nov 2007
    Shooter
    35mm
    Posts
    47
    Dr. Williams' paper illustrates my point very well,

    "Coffee contains just about every type of molecule known to nature, including proteins, lipids and carbohydrates"

    and among them several that might act as developers, but exactly which, and in what proportions, and the quantities of which, no one is saying, and the effects of the myriad other compounds are completely unaccounted for. Effectiveness can be quantified as the quantity of a sunbstance required to produce a given degree of development, and reliability depends on the ability to make a developer of known properties repeatedly from a developer's consituent chemicals. Those definitions would serve well enough for me, anyway.

  8. #28

    Join Date
    Mar 2004
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    3,879
    Images
    11
    Quote Originally Posted by cahayapemburu View Post
    Dr. Williams' paper illustrates my point very well,

    "Coffee contains just about every type of molecule known to nature, including proteins, lipids and carbohydrates"

    and among them several that might act as developers, but exactly which, and in what proportions, and the quantities of which, no one is saying, and the effects of the myriad other compounds are completely unaccounted for. Effectiveness can be quantified as the quantity of a sunbstance required to produce a given degree of development, and reliability depends on the ability to make a developer of known properties repeatedly from a developer's consituent chemicals. Those definitions would serve well enough for me, anyway.
    Thus ignoring the inconvenient fact that film developers that rely on coffee and ascorbic acid as their developing agents actually work and produce very useful and repeatable results.

    Caffeic Acid and Ascorbic Acid - two very interesting anti-oxidants - and both will develop film . Google them.

    For recipes, see: http://silent1.home.netcom.com/Photo...tml#Caffenol_C
    Last edited by Tom Hoskinson; 01-21-2008 at 08:54 AM. Click to view previous post history. Reason: redundant
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

  9. #29
    Jim Noel's Avatar
    Join Date
    Mar 2005
    Shooter
    Large Format
    Posts
    1,846
    Blog Entries
    1
    The only time I decided to use coffee based developer, I used coffee which had been brewed and the remainder left in th pot for a few hours. You know, that stuff that smells so strong youthrow it away and brew fresh.

    I did this prior to reading anything about using Folgers, or any other instant crystals. Also, I had not read much about ascorbic acid. As a result, I just simply added some carbonate to the coffee and developed a couple of sheets of HP5+ by inspection for 25 minutes. The resulting negatives were tanned, thin and very easily printable. subjects in deep shade were hardly visible on the negatives, but printed well. They made excellent prints with palladium.

    Perhaps it is time I tried adding ascorbic acid to speed up the process.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

  10. #30
    Jim Noel's Avatar
    Join Date
    Mar 2005
    Shooter
    Large Format
    Posts
    1,846
    Blog Entries
    1
    Tom,
    I just looked at your Caffenol LC+C.

    I think I will give it a try with lith film as it is simpler and cheaper than LC-1 or altered Rodinal. I like to use lith film in camera to test new lenses.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

Page 3 of 6 FirstFirst 123456 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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