Plus-X speed?

Discussion in 'B&W: Film, Paper, Chemistry' started by JBrunner, Dec 19, 2007.

  1. JBrunner

    JBrunner Moderator Staff Member Moderator

    Messages:
    6,966
    Joined:
    Dec 14, 2005
    Location:
    Basin and Range Province
    Shooter:
    8x10 Format
    Looking for a suggestion for rating Plus-X in Hc110 for N. I don't have time nor enough supplies on hand to figure it out, so I will trust the wisdom of the collective.
     
  2. Photo Engineer

    Photo Engineer Subscriber

    Messages:
    25,436
    Joined:
    Apr 19, 2005
    Location:
    Rochester, N
    Shooter:
    Multi Format
    From the Kodak B&W Darkroom dataguide. PX speed from 50 - 200, nominal speed = 125 when using HC110B for 4 - 6 mins (roll/sheet times).

    PE
     
  3. JBrunner

    JBrunner Moderator Staff Member Moderator

    Messages:
    6,966
    Joined:
    Dec 14, 2005
    Location:
    Basin and Range Province
    Shooter:
    8x10 Format
    Thanks Ron,

    I guess there are advantages to using a Kodak developer with a Kodak film. :smile:
     
  4. Photo Engineer

    Photo Engineer Subscriber

    Messages:
    25,436
    Joined:
    Apr 19, 2005
    Location:
    Rochester, N
    Shooter:
    Multi Format
    When I was there and they had a B&W R&D unit, the standard was D76. Dick Henn had set that up IIRC, and Bill Lee was working on the HC110. Then he passed that on to Dick Dickerson and Sylvia Zawadski when he retired. Then they went on to work on Xtol.

    I'm sure that this is wrong in detail, but is generally right.

    PE
     
  5. gainer

    gainer Subscriber

    Messages:
    3,726
    Joined:
    Sep 20, 2002
    I have not gone wrong using 4 X the box speed for the darkest shadows I want to see into. That amounts to Zone III I reckon, if V is normal.
     
  6. CPorter

    CPorter Member

    Messages:
    1,662
    Joined:
    Feb 2, 2004
    Location:
    West KY
    Shooter:
    4x5 Format
    JB,

    For 120 roll film this worked well for me. When I was shooting 6x7 my tests found that an EI of 64 in dil (h) or 1:63 at 68 deg was very nice. I used a syringe to extract the developer from concentrate. Strangely enough----at 4 min and 30sec in a small tank with agitation at 4 inversions in 5 sec every 30 sec. I was concerned in the beginning that development under 5 minutes was going to be problematic but it really did well.

    Chuck
     
  7. fschifano

    fschifano Member

    Messages:
    3,216
    Joined:
    May 12, 2003
    Location:
    Valley Strea
    Shooter:
    Multi Format
    With proper metering, I've easily gotten good shadows at box speed with this film developed in D-76.
     
  8. DWThomas

    DWThomas Subscriber

    Messages:
    2,823
    Joined:
    Jun 13, 2006
    Location:
    SE Pennsylvania
    Shooter:
    Multi Format
    Having made a quick switch without time to test before a trip, I used PX125 at box speed with D-76 full strength this summer. Shots taken on a hike along woods, streams and waterfalls were quite satisfactory. Metering was my Canon A-1 in "Program" mode -- howzat fer lazy!

    DaveT
     
  9. Photo Engineer

    Photo Engineer Subscriber

    Messages:
    25,436
    Joined:
    Apr 19, 2005
    Location:
    Rochester, N
    Shooter:
    Multi Format
    I'll repeat this more clearly.

    When I was at Kodak, the last time I checked, the release test for B&W films for speed and contrast was D-76 at 68 degrees F. If the PX did not meet the ISO 125 speed and the proper contrast, it was scrap. The times have been published in the same Dataguide I mentioned above, and curves and other info are on the Kodak web site.

    PE
     
  10. gainer

    gainer Subscriber

    Messages:
    3,726
    Joined:
    Sep 20, 2002
    It always seemed to me that Kodak films had a little more "room" at the bottom than some others, which may have been because others took more advantage of the spread allowed in the ISO speed rating. In photographing orchestra members and soloists from my seat in the middle, I depended on consistent shadow speed from roll to roll, batch to batch, and always got it from Kodak, but I used only Tri X. Automatic exposure was useless because of the lighting.
     
  11. Photo Engineer

    Photo Engineer Subscriber

    Messages:
    25,436
    Joined:
    Apr 19, 2005
    Location:
    Rochester, N
    Shooter:
    Multi Format
    Patrick;

    The last time I was involved in checking ISO speeds, we found that indeed many manufacturers played fast and loose with ISO and speeds of some products were as much as one stop out from the ISO standard. This was a particuar problem in color where one layer might be off and the other two on. Or, you might find it varying from batch to batch.

    So, Kodak has always been very careful about making sure that all products, color and B&W, are up to ISO standards in all respects.

    PE