Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,806   Posts: 1,581,389   Online: 1081
      
Page 3 of 6 FirstFirst 123456 LastLast
Results 21 to 30 of 56
  1. #21

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by philldresser View Post
    One of the points I made earlier has not had any comments on yet is the fact that I lost about 1.5 stops (and I am getting a 5.5 stop final density range) of contrast using Sodium Citrate compared to Borax. They look like I have printed on the equivalent of a grade 4.5 silver paper . Is this a known attribute of Sodium Citrate?


    Phill
    Do you mean that you lost 1.5 stops of printing speed or 1.5 stops of tonal range? If the former, I have never compared the printing speed of borax with sodium citrate. However, I have found that sodium citrate gives about the same printing speed as potassium oxalate and ammmonium citrate. I prefer sodium citrate because it is not as toxic as oxalate and is much less expensive.

    The tonal range I get with sodium citrate, with about 2ml of a 5% solution of potassium dichromate added per liter of developer, is about log 1.85, which of course is just slightly more than 6 stops.

    BTW, I have assumed that you were adding some dichromate to the developer. If you do not, it is almost impossible to completely clear the print.

    Sandy King

  2. #22

    Join Date
    Feb 2003
    Location
    Norwich, UK
    Shooter
    Multi Format
    Posts
    1,405
    Images
    90
    Sandy

    I have not added any dichromate to the developer, seems like this maybe the problem.

    Phill
    It is not tradition that secures the survival of our craft, its the craft that secures the survival of our traditions.

  3. #23

    Join Date
    Feb 2003
    Location
    Norwich, UK
    Shooter
    Multi Format
    Posts
    1,405
    Images
    90
    Quote Originally Posted by sanking View Post
    Do you mean that you lost 1.5 stops of printing speed or 1.5 stops of tonal range? If the former, I have never compared the printing speed of borax with sodium citrate. However, I have found that sodium citrate gives about the same printing speed as potassium oxalate and ammmonium citrate. I prefer sodium citrate because it is not as toxic as oxalate and is much less expensive.
    Sandy

    I lose about 1.5 stops of tonal range. Print speed is about the same.

    Phill
    It is not tradition that secures the survival of our craft, its the craft that secures the survival of our traditions.

  4. #24

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by philldresser View Post
    Sandy

    I lose about 1.5 stops of tonal range. Print speed is about the same.

    Phill
    How are you determining that you lost 1.5 stops of tonal range? Are you using a step wedge? If so, from where to where on the print scale are you counting? Just so we are on the same page, for in-camera negatives I count from about 90% of maximum black to paper white. For in-camera negatives, from maximum black to paper white.

    Sandy

  5. #25

    Join Date
    Feb 2003
    Location
    Norwich, UK
    Shooter
    Multi Format
    Posts
    1,405
    Images
    90
    Quote Originally Posted by sanking View Post
    How are you determining that you lost 1.5 stops of tonal range? Are you using a step wedge? If so, from where to where on the print scale are you counting? Just so we are on the same page, for in-camera negatives I count from about 90% of maximum black to paper white. For in-camera negatives, from maximum black to paper white.

    Sandy
    I have printed the same negative twice, both with step wedge and used different developers as discussed. The Borax print shows an increased tonal range compared to the Sodium Citrate developer between 1 and 1.5 stops. The range is measured (by eye) from first discernable non black to last discernable tone before white. This is 11 steps (3B - 14W) for sodium citrate and 13/14 steps for Borax/Rochelle (3B - 16/17W). The only other difference was dev temperature where the Borax solution was around 40C. Sodium Citrate was between 18-20C.

    Here is one of the 5x4 pics deved on Wed in Sodium Citrate showing the rich chocolate colour entitled ' Unfolding'. This is the image with no staining. The Tonal range on the original goes to step 14, scan does not reflect this as I haven't mastered scanning yet

    It is not tradition that secures the survival of our craft, its the craft that secures the survival of our traditions.

  6. #26

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by philldresser View Post
    I have printed the same negative twice, both with step wedge and used different developers as discussed. The Borax print shows an increased tonal range compared to the Sodium Citrate developer between 1 and 1.5 stops. The range is measured (by eye) from first discernable non black to last discernable tone before white. This is 11 steps (3B - 14W) for sodium citrate and 13/14 steps for Borax/Rochelle (3B - 16/17W). The only other difference was dev temperature where the Borax solution was around 40C. Sodium Citrate was between 18-20C.

    Here is one of the 5x4 pics deved on Wed in Sodium Citrate showing the rich chocolate colour entitled ' Unfolding'. This is the image with no staining. The Tonal range on the original goes to step 14, scan does not reflect this as I haven't mastered scanning yet

    Well, that is certainly good rich Dmax, and you do not appear to have staining. BTW, temperature of developer does affect tonal range. You need to compare the borax and sodium citrate developers at the same temperature. Higher temperatures increase ES with most developers.

    Sandy

  7. #27

    Join Date
    Nov 2002
    Location
    Massachusetts
    Shooter
    8x10 Format
    Posts
    93
    I just tested the pH of my sodium citrate and it was quite alkaline -- something on the order of 8.5 or higher. I added about 5 grams of citric acid to 1.5 liters of the stock sodium citrate (no potassium dichromate added) and the pH is now acidic -- somewhere at or below 6.5. I left the dichromate out of the equation since I thought its orange color might confuse my reading of the pH strips.

    Anyone know if the addition of the dichromate will alter the pH by much?

    Sandy, thanks for the heads up on the pH of the developer. I just assumed it was acidic. Me and my assumptions....

    -Paul

  8. #28

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by Paul View Post
    I just tested the pH of my sodium citrate and it was quite alkaline -- something on the order of 8.5 or higher. I added about 5 grams of citric acid to 1.5 liters of the stock sodium citrate (no potassium dichromate added) and the pH is now acidic -- somewhere at or below 6.5. I left the dichromate out of the equation since I thought its orange color might confuse my reading of the pH strips.

    Anyone know if the addition of the dichromate will alter the pH by much?

    Sandy, thanks for the heads up on the pH of the developer. I just assumed it was acidic. Me and my assumptions....

    -Paul
    Yeah, me to, for a long time. Then I tested it and got a big surprise. The trisodium type of sodium citrate (C6H5Na3O7), which is very common, is slighly alkaline, but you can make it work easily by adjusting pH with citric acid. I think there is also a disodium acidic type, but if so it is much less common in the marketplace.

    Sandy King

  9. #29
    Dug
    Dug is offline

    Join Date
    Feb 2004
    Location
    Seattle WA USA
    Shooter
    Multi Format
    Posts
    123

    New Type of Kallitype Stain Question

    Now that the brightest Kallitype minds are talking about staining:

    I only have a staining problem during the Pd toning of the Kallitype

    Single coated Bergger COT320 or Rising Stonehenge paper
    Sodium Citrate Developer
    Citric Acid Clear

    After rinsing and placing the print in the Pd toner from Sandy King's article, every once in a while a dark red contamination appears in the toning bath, spreads, and stains the paper in an even yellow/brown tone.

    I have cleaned and monitored all the process and have dedicated a tray to the Pd toning to prevent contamination. Most of the time everything work out fine, but I get varying degrees of staining from the toning process.

    Any thoughts?

  10. #30

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by Dug View Post
    Now that the brightest Kallitype minds are talking about staining:

    I only have a staining problem during the Pd toning of the Kallitype

    Single coated Bergger COT320 or Rising Stonehenge paper
    Sodium Citrate Developer
    Citric Acid Clear

    After rinsing and placing the print in the Pd toner from Sandy King's article, every once in a while a dark red contamination appears in the toning bath, spreads, and stains the paper in an even yellow/brown tone.

    I have cleaned and monitored all the process and have dedicated a tray to the Pd toning to prevent contamination. Most of the time everything work out fine, but I get varying degrees of staining from the toning process.

    Any thoughts?
    Never seen anything like this. Must be some kind of contamination from something outside of the normal chemicals we use in the process.

    Sandy

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