Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,921   Posts: 1,584,927   Online: 1007
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 19

Thread: BTZS Request

  1. #1
    chrisf's Avatar
    Join Date
    Dec 2004
    Shooter
    Large Format
    Posts
    77

    BTZS Request

    Hi,

    I recently bought the expo/dev software for my palm. The film database doesn't include pyrocat hd as a developer.

    Could someone email me curves for FP4+ and Efke 25 both in Pyrocat Hd rotary processed, in the format used in the database?

    Thanks,
    chris

  2. #2
    jeroldharter's Avatar
    Join Date
    Nov 2005
    Location
    Wisconsin
    Shooter
    4x5 Format
    Posts
    1,958
    Images
    1
    I've never used pyro developers. My understanding is that the data is not in the software, because pyro does not behave well with BTZS methods.

    You should call the View Camera Store and ask. You might need to test for yourself if nobody responds. I did two of their film tests for TMAX 100 in different developers and it worked out well. They do the sensitometer readings and then email you the plotter file.
    Jerold Harter MD

  3. #3

    Join Date
    Mar 2004
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    3,879
    Images
    11
    Quote Originally Posted by jeroldharter View Post
    I've never used pyro developers. My understanding is that the data is not in the software, because pyro does not behave well with BTZS methods.

    You should call the View Camera Store and ask. You might need to test for yourself if nobody responds. I did two of their film tests for TMAX 100 in different developers and it worked out well. They do the sensitometer readings and then email you the plotter file.
    In my experience, Pyro developers (in general) and Pyrocat in particular, behave very well when used with the BTZS methodology. I have published D logE curves for TMY developed in Pyrocat on APUG. If I recall correctly, Sandy King has published data for FP4 developed in Pyrocat on APUG.
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

  4. #4
    Robert Hall's Avatar
    Join Date
    Aug 2004
    Location
    Lehi, Utah
    Shooter
    ULarge Format
    Posts
    2,040
    Images
    28
    Phil was never a fan of Pyro for a few reasons. One was that due to the stain having effects on VC papers it was not easily measured. Second after the issues of alt uses for the negs, such as Platinum processes etc. One could not easily measure the stains effect on UV. This measurement issue was the same reason he was not a fan of IR films.

    Phil went through dozens of developers for testing and really, while I use PMK for pretty much everything, I have to agree. If you follow the BTZS plan, it works with any standard developer.

    If you really want more technical advice, we have several efficianados here as well as Fred at the View Camera Store down in Arizona.
    Robert Hall
    www.RobertHall.com
    www.RobertHall.com/mobile
    Apug Portfolio
    Facebook Profile


    Technology is not a panacea. It alone will not move your art forward. Only through developing your own aesthetic - free from the tools that create it - can you find new dimension to your work.

  5. #5
    juan's Avatar
    Join Date
    May 2003
    Location
    St. Simons Island, Georgia
    Shooter
    Multi Format
    Posts
    1,646
    Images
    4
    I don't think Fred is a fan of pyro, so he might not be able to help. I use pyrocat with BTZS and it works very well. I don't, however, have data for those two films.
    juan

  6. #6

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Chris,

    I am not sure what you mean by a film databse compatible with the expo/dev software.

    If you use Winplotter, which I assume you do since you have BTZS, I can send you a file for the PC which has data for FP4+ developed in Pyrocat-HD. I don't believe I have anything on Efke 25, but could check.

    My recollection is that I simply keyed in the development data from the Winplotter file to the PDA and assume you could do the same.

    Phil Davis did not use Pyro type developers because in his opinion the stain made it impossible to work with the kind of precision he liked with VC silver papers. I suspect that Fred Newman feels the same.

    In spite of that my own belief is that Pyro staining developers have some very desirable characteristics that make their use worthwhile, even if the stain does interfere some with the absolute precision of BTZS.

    Sandy King


    Quote Originally Posted by chrisf View Post
    Hi,

    I recently bought the expo/dev software for my palm. The film database doesn't include pyrocat hd as a developer.

    Could someone email me curves for FP4+ and Efke 25 both in Pyrocat Hd rotary processed, in the format used in the database?

    Thanks,
    chris

  7. #7
    chrisf's Avatar
    Join Date
    Dec 2004
    Shooter
    Large Format
    Posts
    77
    Sandy,

    Thanks for your response. I do have the expo/dev software on my brother's pc since I use an older Mac. I didn't buy the Plotter software separately and I don't know if it came with the expo/dev. I'll take a look tonight. That'll be great if you could send me the file. slipperysilks1936 at yahoo

    chris

  8. #8

    Join Date
    Oct 2002
    Posts
    1,160
    I believe that part of the "problem" with Pyro and BTZS has to do with the ability of many densitometers to read the correct densities of negatives developed in Pyro and derivatives. Sandy would obviously be able to comment with much more knowldege then I.

    Edwin

  9. #9

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Edwin,

    Basically, BTZS works with full precision with pyro staining developers if you print on graded silver papers. You simply take density readings with the blue channel of the densitometer. Most B&W densitometers will also work if you use a blue filter (47 or 47b) and zero it out before taking a reading.

    BTZS will also work with full precision with pyro stained negatives and alternative processes sensitive to UV light if you take a reading with the densitometer in UV mode. Problem is not many densitometers are capable of UV readings.

    VC silver papers are more difficult to work with using BTZS and stained negatives because they have two kinds of sensitivity, blue and green, and which one is being used varies according to the filtration in use. This makes it impossible to get full BTZS precision with these type of papers and pyro stained negatives.

    Sandy King



    Quote Originally Posted by Mahler_one View Post
    I believe that part of the "problem" with Pyro and BTZS has to do with the ability of many densitometers to read the correct densities of negatives developed in Pyro and derivatives. Sandy would obviously be able to comment with much more knowldege then I.

    Edwin

  10. #10

    Join Date
    Mar 2004
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    3,879
    Images
    11
    Quote Originally Posted by Robert Hall View Post
    Phil was never a fan of Pyro for a few reasons. One was that due to the stain having effects on VC papers it was not easily measured. Second after the issues of alt uses for the negs, such as Platinum processes etc. One could not easily measure the stains effect on UV. This measurement issue was the same reason he was not a fan of IR films.

    Phil went through dozens of developers for testing and really, while I use PMK for pretty much everything, I have to agree. If you follow the BTZS plan, it works with any standard developer.

    If you really want more technical advice, we have several efficianados here as well as Fred at the View Camera Store down in Arizona.
    Robert, I routinely measure the UV densities of my stain images with my Heiland TD2 Black and White Densitometer. I have a UV probe and a Silver-Visual probe for the densitometer.

    BTW I am very pleased with my Heiland Densitometer and the personal service and probe advice given to me by Juergen Heiland.
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

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