Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,897   Posts: 1,521,015   Online: 820
      
Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 32
  1. #11
    donbga's Avatar
    Join Date
    Nov 2003
    Shooter
    Large Format Pan
    Posts
    2,056
    Quote Originally Posted by philsweeney
    For most of my kallitype printing I have tailored the negative so I can use 4ml pot dichromate in the sodium citrate. So the negative needs to be about 1.5 log. Is there any good reason to consider tailoring my negatives for using 1ml dichromate, which will require a negative log of 1.75 - 1.8?
    Why use potassium dichromate at all if you are attempting to build a negative with a DR to match the process?

    As for even coating of the paper, what paper are you using and how are you coating it? Also what is the relative humidity of your coating environment?

    A textured paper surface requires more sensitizer than hot press paper.

    One thing that may help with even coating is to add a couple of drops of grain alcohol to the sensitizer for an 8x10 size print.

    Good luck,

    Don Bryant

  2. #12
    Stan. L-B's Avatar
    Join Date
    Jun 2004
    Location
    London & Friars Cliff Dorset UK
    Shooter
    8x10 Format
    Posts
    342
    Images
    1
    Phil.
    Have you tried Fabrino 140lb water colour paper?

    And, I note you are using dichromate and sodium citrate for your Ks. where the normal chemistry for Ks here is, ferric oxalate with silver nitrate. I have no experience of your formula. As with all these processes, a slight change of the formula used, gives different tone.
    'Determine on some course more than a wild exposure to each chance' The Bard.

  3. #13

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by Stan. L-B
    Phil.
    Have you tried Fabrino 140lb water colour paper?

    And, I note you are using dichromate and sodium citrate for your Ks. where the normal chemistry for Ks here is, ferric oxalate with silver nitrate. I have no experience of your formula. As with all these processes, a slight change of the formula used, gives different tone.
    Stan,

    The normal chemistry for the kallitype sensitizer on this side of the pond is also ferric oxalate and silver nitrate, more specifically a 1:1 mixture of a 20% solution of ferric oxalate with a 10% solution of silver nitrate.

    What Phil and Don are talking about is adding small amount of potassium dichromate to the developer, in this case sodium citrate, to control contrast. When you use sodium citrate as the developer it is possible to adjust the amount of dichromate in the developer from virtually none to as much a about 16ml of a 5% solution per liter of developer to match negatives with DRs that range from about 1.3 to as much as 2.0 or slightly higher.

    As for the Fabriano water color papers none of these have worked well for me in recent years with kallitype. Both artistico and uno give prints of rather low Dmax. Dmax can be increased slightly with an oxalic acid soak of the Fabriano papers but it remains unacceptably low in my estimation even with this procedure.

    There are a number of other developers that one can use with kallitype, including potassium oxalate which is my second choice behind sodium citrate. Assuming that you will tone your kallitypes, as one surely should if permanence is of any concern, the choice of developer is not very important since the final image will take on the tone of the toning metal, regardless of which developer you use.

    Sandy King

  4. #14

    Join Date
    Sep 2003
    Posts
    178
    Quote Originally Posted by donbga
    Why use potassium dichromate at all if you are attempting to build a negative with a DR to match the process?
    Don Bryant
    Don, I thought using some dichromate would put me in the middle so if I needed less contrast I could reduce the dichromate and increase for more contrast. Plus I can reduce neg. developing time a little. My question is to try and realize if there are qualities of a print that are more desirable if I used less or no dichromate?

    Papers I like so far are socorro and strathmore 400 watercolor. I have no problem coating these. I do need an oxalic acid soak for both.

  5. #15
    donbga's Avatar
    Join Date
    Nov 2003
    Shooter
    Large Format Pan
    Posts
    2,056
    Hi Phil,

    I thought that might be your rationale, personally I prefer to avoid dichromate usage when ever possible. If you use dichromate how do you replenish the developer?

    I've been using Bergger Cot 320 and have been very happy with it (except the price). I've just order some Stonehenge Rising and Lenox to work with (much cheaper too).

    Don

  6. #16

    Join Date
    Sep 2003
    Posts
    178
    I replenish per sandy king's article on kallitypes. I keep a second bottle with the appropriate amount of dichromate in it for topping off.

    I want to try the cot-320. Does it need an oxalic acid bath for kallitype? Unfortunately I had no luck with the stonehenge rising, maybe I got a funky batch? I also had no luck with the artistico. Crane's platinotype is OK with no oxalic acid but I find the paper too delicate and I have to handle it very gently.

  7. #17
    mikepry's Avatar
    Join Date
    Mar 2003
    Location
    Salem, Wi (By Milwaukee)
    Shooter
    8x10 Format
    Posts
    413
    Images
    40
    I too, have just tried the Cott 320 and it is magnificent. It is the nicest paper I have worked with. Luxuriant comes to mind. I don't use oxalic acid with it. I balked at the price at first but then when it comes right down to it when you think of all the work one goes through to get to the point when you actually make a print.....it really isn't that much more. The results negated any qualms I had about price.

  8. #18
    donbga's Avatar
    Join Date
    Nov 2003
    Shooter
    Large Format Pan
    Posts
    2,056
    Quote Originally Posted by philsweeney
    I replenish per sandy king's article on kallitypes. I keep a second bottle with the appropriate amount of dichromate in it for topping off.

    I want to try the cot-320. Does it need an oxalic acid bath for kallitype? Unfortunately I had no luck with the stonehenge rising, maybe I got a funky batch? I also had no luck with the artistico. Crane's platinotype is OK with no oxalic acid but I find the paper too delicate and I have to handle it very gently.
    So if you wanted to print negatives with different DR you would have to maintain 2 bottles for each dilution, which seems very tedious.

    The COT 320 doesn't require any pre-treatment. I've used it with several different processes (VDB, cyanotype, palladium/platinum DOP, and ziatypes) with good results. It does have signifigant dry down.

    What kind of problem did you have with Stonehenge? I've also got some Lenox ordered, it would be nice to have a good inexpensive paper.

    Platinotype is an okay paper but it does tend to tear when handling large wet sheets.

    Don

  9. #19
    donbga's Avatar
    Join Date
    Nov 2003
    Shooter
    Large Format Pan
    Posts
    2,056

    COT 320

    Quote Originally Posted by mikepry
    I too, have just tried the Cott 320 and it is magnificent. It is the nicest paper I have worked with. Luxuriant comes to mind. I don't use oxalic acid with it. I balked at the price at first but then when it comes right down to it when you think of all the work one goes through to get to the point when you actually make a print.....it really isn't that much more. The results negated any qualms I had about price.
    Art Craft Chemicals seems to have the best price for COT 320 but only slightly less than Bostick & Sullivan.

    FWIW, Bergger makes one of the best inkjet papers for quad tone printing I've ever used, but it is *REALLY* expensive.

    Don

  10. #20

    Join Date
    Sep 2003
    Posts
    178
    Quote Originally Posted by donbga
    What kind of problem did you have with Stonehenge? I've also got some Lenox ordered, it would be nice to have a good inexpensive paper.
    Don
    The stonehenge I received sucked up the coating too much and image density was poor.

Page 2 of 4 FirstFirst 1234 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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