How do I know if it is really AZO?

Discussion in 'B&W: Film, Paper, Chemistry' started by 2F/2F, Dec 9, 2008.

  1. 2F/2F

    2F/2F Member

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    I purchased a fridge full of b/w and Cibachrome paper some time ago for $20. Most is OLD ('40s through '60s) and fogged a few stops, and I have been having some fun with it here and there when I get the time.

    Among it is:

    100 sheet box 8x10 AZO F-2 single weight

    250 sheet box 8-1/2x11 AZO E-4 single weight

    The problem is that a lot of this paper is obviously stored in the wrong boxes. How do I know if this really is AZO?

    I ask because I know some people have a special affinity for this particular paper, while I have not developed one, and DO NOT want to develop one, since the stuff isn't made any more. If it is AZO, I want to give it to someone who will really appreciate it in applications where fogged paper won't hurt the image.

    Thank you in advance.
     
    Last edited by a moderator: Dec 9, 2008
  2. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Well, it should be easy to determine whether the paper in the boxes that say "single weight" are single weight, so that would be one indicator.

    F surface is glossy, and E surface is luster, so that would be another indicator if the paper were in the marked box.

    Then you could test the paper speed against an enlarging paper and see if it's much slower than enlarging paper, and that would be another indicator that it is Azo.

    Azo holds up remarkably well to aging, so if it has been refrigerated or frozen all of its life, it may not have very much fog at all.
     
  3. Photo Engineer

    Photo Engineer Subscriber

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    Velite and Velox paper were very similar and had the same grades and surfaces as well as speed. So, the only definitive way would be to do as David says above and then compare it with vintage Azo paper for overall characteristics.

    With the changes made to Azo over the years, without an authentic vintage sample it would be hard to tell at this remove without them being in original sealed boxes.

    PE
     
  4. nworth

    nworth Subscriber

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    You can't tell without making controlled sensitometry tests, but you can probably get a good idea. First, Azo was a very slow contact paper. If a sheet shows anything with a generous enlarging exposure, it isn't Azo. Second, check out the surfaces and contrast grades. F-2 is a normal contrast, white, glossy, smooth paper. E-4 is a high-contrast, white, luster, fine-grained (pebbly) surface. When processed as a normal black and white paper, Cibachrome will look pretty black, especially if you process it under a safelight.
     
  5. sun of sand

    sun of sand Member

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    I think you could develop it out and check the color of the paper/fog
    Not sure if it matters whether you leave in the developer for an inordinate amount of time or not
    Leave piece in for couple minutes and another for much longer?
    High chloride paper such as azo would -i believe- have a yellow foggy appearance as opposed to...whatever for bromide papers/chlor-bromide

    speed is obviously the easiest way to discern between enalrging and contact paper
    try enlarging on it
     
  6. sun of sand

    sun of sand Member

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    I'll take the "E-4 Azo" wink wink for $20 and just do it myself
    you send paper and $20
     
  7. Michael Kadillak

    Michael Kadillak Member

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    Being perfectly honest, the value of old Azo has been significantly diminished by the introduction of Lodima paper for which the first test run of the paper is being shipped the second week of Dec 2008. Prior to the introduction of Lodima, Azo commanded high prices within the secondary markets and that condition no longer exists.

    The reason is simple. Lodima is double weight paper that is nowhere near as fragile as Azo and is a modern newly formulated emulsion currently in production. Secondly. Lodima has been shown in preliminary testing to be a superior silver chloride paper to Azo.

    A standard production sales program will be introduced after the test paper has been delivered that will allow customers of this product to make a financial commitment to it. My hope is that people will see the marvels of this product and will step up in numbers to allow it to be manufactured in significant quantity.

    Why would you want the old when you can have the new and improved?

    Cheers!
     
  8. jd callow

    jd callow Moderator Staff Member Moderator

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    he doesn't want it. He wants to give it away, would like to know what it is prior to doing so and it is free.
     
    Last edited by a moderator: Dec 10, 2008
  9. gbenaim

    gbenaim Member

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    Azo generally holds up very well over time, so lack of fog would be a good indicator, as would single weight and slow speed. You need at least a 100w-200w bulb a couple of feet from the paper for 10-30 secs to get an exposure. Its print color can also be an indicator, as it goes bluish in dektol and greenish in warmer tone developers. The easiest way to know for sure is to send some to someone who uses the stuff (I'll volunteer), and they can easily tell. Just for comparison's sake, I have some azo from the 40s in 4x5 that has lost some contrast, but still prints well.
     
  10. jnanian

    jnanian Advertiser Advertiser

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    2F/2F

    if you make a photogram with it, using a 300w light bulb
    process it in dektol, if it has a greenish cast, it might be azo ..

    have fun!

    john