Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,572   Posts: 1,545,647   Online: 967
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1
    Sirius Glass's Avatar
    Join Date
    Jan 2007
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    13,128

    C-41 Process Glass or Plastic bottles?

    I have decided to do my own C-41 film processing. I will be using a steel tank in a large steel sink filled with water at 102 degrees F. I will mix the chemical just prior to processing the film. My question is should I use glass or plastic bottles to get the temperature of the chemical to stabilize faster?

    Steve
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  2. #2
    tim_walls's Avatar
    Join Date
    Sep 2006
    Location
    Croydon & Leeds
    Shooter
    35mm
    Posts
    1,037
    Images
    48
    Quote Originally Posted by Stever View Post
    I have decided to do my own C-41 film processing. I will be using a steel tank in a large steel sink filled with water at 102 degrees F. I will mix the chemical just prior to processing the film. My question is should I use glass or plastic bottles to get the temperature of the chemical to stabilize faster?

    Steve
    My only experience is that I use plastic bottles for E6 with no problem whatsoever.

    I plugged some numbers into Fourier's Law however to try and work it out, purely out of curiosity. Bear in mind I last studied science about 15 years ago though :-).


    According to the Intarweb, thermal conductivity of PVC is around 0.19 W/mK, glass 1.05 W/mK.

    The thickness of the bottles will make a big difference. Running the numbers for a plastic bottle with walls half a millimetre thick, and a glass bottle with walls 3mm thick, you're looking at about the same. If the glass bottle were 2mm thick instead of 3, the glass would be about 50% faster. If it were 4mm thick though, it would be about 50% slower...


    Or to put it another way; use whichever is most convenient, it doesn't make that much difference ;-)
    Another day goes under; a little bourbon will take the strain...

  3. #3
    tim_walls's Avatar
    Join Date
    Sep 2006
    Location
    Croydon & Leeds
    Shooter
    35mm
    Posts
    1,037
    Images
    48
    ...Oh, and one other thing; that assumes both bottles present the same surface area.

    A square bottle of say 10cm x 10cm has a 'circumference' if you can call it that of 4x10=40cm. A bottle of diameter 10cm (i.e. a round bottle which will fit into the same space as the square one) has a circumference of πD = 3.141 * 10 = 31.41cm.

    The square bottle will therefore present a surface area (assuming it's a 'straight up and down' bottle) approximatly 1.3 times that of the round one. If you plug the numbers back into Fourier, that brings a square PVC bottle with .5mm thick walls back more or less into line with a round glass bottle with only 2mm thick walls.


    One of those plastic accordion (squeezy) bottles is going to present a much larger surface area again, of course...


    Err, like I said. Use whichever is most convenient :-)
    Another day goes under; a little bourbon will take the strain...

  4. #4

    Join Date
    Nov 2004
    Location
    Italia
    Shooter
    Multi Format
    Posts
    4,680
    I use a mix of glass and plastic for C-41 and RA-4.

    Bleach goes into plastic. It doesn't mind oxygen.

    Developer goes into glass.

    If you're using a water math the plastic bottles can be light enough to float!!#@$#$@.

    Oh the question was about speed? If it warms up quicker it'll cool down quicker.

  5. #5

    Join Date
    Oct 2006
    Location
    Van Buren, Arkansas
    Shooter
    Large Format
    Posts
    2,412
    Images
    101
    I have always used plastic bottles for all color chemistry with zero problems or issues. Kodak ships everything in plastic bottles now.

  6. #6
    Dave Miller's Avatar
    Join Date
    Dec 2003
    Location
    Middle England
    Shooter
    Medium Format
    Posts
    3,894
    Images
    2
    Quote Originally Posted by PHOTOTONE View Post
    I have always used plastic bottles for all color chemistry with zero problems or issues. Kodak ships everything in plastic bottles now.
    That's true, but it's got to be the right type of plastic!
    Regards Dave.

    An English Eye


  7. #7

    Join Date
    Oct 2006
    Location
    Van Buren, Arkansas
    Shooter
    Large Format
    Posts
    2,412
    Images
    101
    Quote Originally Posted by Dave Miller View Post
    That's true, but it's got to be the right type of plastic!
    Well, if you purchase bottles from a photo supplies vendor, they ARE the right type, however.....

    For over 20 years I have used 1/2 gallon clorox bleach bottles for E-6 chemistry with excellent results. You can get these by prowling around the trash cans at laundromats. Just rinse them out well, with multiple fills of water.

  8. #8
    Bob F.'s Avatar
    Join Date
    Oct 2004
    Location
    London
    Shooter
    Multi Format
    Posts
    3,984
    Images
    19
    I note that Ilford ship their chemicals in HDPE. Most non-specialist plastic bottles such as fizzy pop and water bottles appear to be PET but they seem to work OK for most things - I've had ID11 for over a year in such bottles. The accordion bottles I have are not marked.

    I don't think there is much between plastic and glass for heat transmission. They are both good insulators but are both quite thin in this use.

  9. #9

    Join Date
    Dec 2005
    Location
    Hollis, NH
    Shooter
    35mm
    Posts
    732
    Images
    3
    Quote Originally Posted by Stever View Post
    I have decided to do my own C-41 film processing. I will be using a steel tank in a large steel sink filled with water at 102 degrees F. I will mix the chemical just prior to processing the film. My question is should I use glass or plastic bottles to get the temperature of the chemical to stabilize faster?

    Steve
    I would say plastic. I have both glass and plastic bottles, and I can tell you that when I am cleaning them, I use very hot water. When I fill a glass bottle, I have no problem holding it and dumping it. When I fill a plastic bottle, it rapidly (almost immediately) becomes uncomfortable to hold.

  10. #10
    Sirius Glass's Avatar
    Join Date
    Jan 2007
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    13,128
    Thank you for yor responses. I will be going back to Freestyle Friday to pick up some more plastic bottles.

    Steve
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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