Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,217   Posts: 1,532,141   Online: 1039
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 14
  1. #1
    lee
    lee is offline
    lee's Avatar
    Join Date
    Nov 2002
    Location
    Fort Worth TX
    Shooter
    8x10 Format
    Posts
    2,913
    Images
    8

    sodium carbonate in Pyrocat-HD

    Sandy or any other expert,
    I have been developing in Pyrocat-HD and using sodium carbonate per Don Miller's instructions. I am mixing it 1:5:100 for silver and 2:10:100 for alt and Azo. What I am seeing is a drop in temp from when I start the development and I am wondering if the carbonate is causing this and if that is the case how can I account for it in my timing?

    thanks,
    lee\c

  2. #2

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by lee
    Sandy or any other expert,
    I have been developing in Pyrocat-HD and using sodium carbonate per Don Miller's instructions. I am mixing it 1:5:100 for silver and 2:10:100 for alt and Azo. What I am seeing is a drop in temp from when I start the development and I am wondering if the carbonate is causing this and if that is the case how can I account for it in my timing?

    thanks,
    lee\c
    I have not used sodium carbonate in the Pyrocat-HD formula for several years but when I was using it I never noticed any drop in temperature, and don't know of any reason why that should happen.

    But it sure seems very odd to me that the temperature of the solution would drop in Forth Worth during the summer.

    What kind of temperature drop are you experiencing?

    Sandy

  3. #3

    Join Date
    Sep 2002
    Shooter
    Large Format
    Posts
    4,530
    Quote Originally Posted by lee
    Sandy or any other expert,
    I have been developing in Pyrocat-HD and using sodium carbonate per Don Miller's instructions. I am mixing it 1:5:100 for silver and 2:10:100 for alt and Azo. What I am seeing is a drop in temp from when I start the development and I am wondering if the carbonate is causing this and if that is the case how can I account for it in my timing?

    thanks,
    lee\c
    Lee, dissolving sodium carbonate in water is an exothermic reaction. It generates heat and heats up the carbonate solution. Since you are using 5 parts per 100, this might be enough to raise the temperature of the entire developer a few degrees. As you start developing you will experience a drop in temperature if you just mixed the carbonate and used it immediately.

    Hope this helped.

  4. #4
    lee
    lee is offline
    lee's Avatar
    Join Date
    Nov 2002
    Location
    Fort Worth TX
    Shooter
    8x10 Format
    Posts
    2,913
    Images
    8
    Quote Originally Posted by Jorge
    Lee, dissolving sodium carbonate in water is an exothermic reaction. It generates heat and heats up the carbonate solution. Since you are using 5 parts per 100, this might be enough to raise the temperature of the entire developer a few degrees. As you start developing you will experience a drop in temperature if you just mixed the carbonate and used it immediately.

    Hope this helped.
    Jorge,
    thanks I seem to remember that from some other site I think. I mixed the part a and part b several days ago. When I am ready to develop film I am aiming for Azo so according to directions I mix in the 2:10:100. Tray developing. I measure out 20 ml of Part A and 100 ml of Part B and 1000 ml of h2o This is at 78f or so (I have a zone 6 compensating timer) This gets poured into one tray and off we go. I measured the temp after the first run of film and the temp was about 74f. So, is that what is going on?

    lee\c

  5. #5

    Join Date
    Sep 2002
    Shooter
    Large Format
    Posts
    4,530
    Quote Originally Posted by lee
    Jorge,
    thanks I seem to remember that from some other site I think. I mixed the part a and part b several days ago. When I am ready to develop film I am aiming for Azo so according to directions I mix in the 2:10:100. Tray developing. I measure out 20 ml of Part A and 100 ml of Part B and 1000 ml of h2o This is at 78f or so (I have a zone 6 compensating timer) This gets poured into one tray and off we go. I measured the temp after the first run of film and the temp was about 74f. So, is that what is going on?

    lee\c
    Nope, the solution is being cooled down to your normal room temp. 78 ºF is somewhat hot to start, I am not surprised your final temp is 74º, you are probably running your house AC at about 68 to 70 ºF. I dont see the problem. Besides what do you care? that is what the Zone VI compensating timer is for. I have one and dont worry about the temp.

    OTOH if you are really getting annoyed by this, a water jacket should do the trick.

  6. #6
    lee
    lee is offline
    lee's Avatar
    Join Date
    Nov 2002
    Location
    Fort Worth TX
    Shooter
    8x10 Format
    Posts
    2,913
    Images
    8
    the room is about 75f so that may be it. I just was shocked to see the temp be that far low after 12 minutes or so.

    thanks and see ya next week in Mexico

    lee\c

  7. #7

    Join Date
    Dec 2002
    Shooter
    Large Format
    Posts
    6,242
    My summer temp developer temp is about 74 degrees...winter temp is 70 degrees in the tempered water bath...with the Zone VI comp timer that is close enough for what I do.

  8. #8
    lee
    lee is offline
    lee's Avatar
    Join Date
    Nov 2002
    Location
    Fort Worth TX
    Shooter
    8x10 Format
    Posts
    2,913
    Images
    8
    thanks don I am gonna call JandC tomorrow and order a box of Efke 100 I just don't have any faith in the TMY

    lee\c

  9. #9

    Join Date
    Jul 2003
    Location
    Texas
    Shooter
    Multi Format
    Posts
    3,576
    Images
    27
    Lee, Jorge, Donald et al,,,,so how does a comp. timer work? Do you input the values you would use at say 68 F, and it will adjust to the acutal temp? That would make life a little easier if that is how it works.

    Thanks,
    Mike
    Mike C

    Rambles

  10. #10

    Join Date
    Sep 2002
    Shooter
    Large Format
    Posts
    4,530
    Quote Originally Posted by photomc
    Lee, Jorge, Donald et al,,,,so how does a comp. timer work? Do you input the values you would use at say 68 F, and it will adjust to the acutal temp? That would make life a little easier if that is how it works.

    Thanks,
    Mike
    It has a probe you put in the developer or water jacket and the timer speeds up or slows down depending at which temp it was calibrated. Zone VI or Calumet sends them calibrated at 68 ºF, but I modified mine to read as "normal" time at 74 ºF.

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