Page 2 of 2 FirstFirst 12
Results 11 to 13 of 13

Thread: Anomaly in exposure testing

  1. #11

    Join Date
    Dec 2009
    Location
    Pacifica, CA
    Posts
    1,522

    Re: Anomaly in exposure testing

    When you exposed properly for Zone VII and tried to print it to be Zone VII, you found the Zone IV was too thin, printed too dark.

    I think you underdeveloped. You have a flat negative. You may have chosen the time for D23 stock instead of for D23 at 1:1.

    Recommend re-doing the test, keep it same - the tan towel at Zone VII wasn't a bad idea and the black t-shirt falling around Zone IV should give you a good range to work with.

    But develop for 13 minutes or more.

  2. #12

    Join Date
    Apr 2015
    Location
    Purcellville, VA
    Posts
    165

    Re: Anomaly in exposure testing

    Quote Originally Posted by stawastawa View Post
    to test the metering see if you can locate some different meters to compare.
    My Luna-Pro F matches my Pentax extremely well. Both could be wrong, but as noted, I created a good Zone I with the tan towel placed on I using the same meter; it was the discrepancy between that and placing the black shirt on the same value that raised my question mark.
    Philip U.

    Sine scientia ars nihil est.

  3. #13

    Join Date
    Apr 2015
    Location
    Purcellville, VA
    Posts
    165

    Re: Anomaly in exposure testing

    Quote Originally Posted by Bill Burk View Post
    When you exposed properly for Zone VII and tried to print it to be Zone VII, you found the Zone IV was too thin, printed too dark.

    I think you underdeveloped. You have a flat negative. You may have chosen the time for D23 stock instead of for D23 at 1:1.

    Recommend re-doing the test, keep it same - the tan towel at Zone VII wasn't a bad idea and the black t-shirt falling around Zone IV should give you a good range to work with.

    But develop for 13 minutes or more.
    Thanks for your response. Perhaps my writing is unclear. By "meter 7," I mean the Pentax's number, not Zone VII. I placed the tan towel on Zone VI as stated, which read as 7 on the meter scale, which I believe is in the EV (exposure value) scale. In any case, having read, placed, developed and proper-proof printed (Fred Picker, ZoneVI Workshop, etc.) both a Zone I and Zone III from the tan towel, with other values falling appropriately (the Zone III was, if anything, a teence high), I remain curious about the anomaly. If time allows, I will retest this weekend, in various ways, to see what transpires.

    I would only add, that this test came after a couple of months of available-time testing with HP5 and D-23 to establish basic exposure and an array of development times and procedures for N+2 through N-2, including tray and rotary processing, stock, 1:1, 1:3, and two-bath (with Borax). This test used Normal rotary processing and was meant as a concluding check of previous testing results. I will post back one I have more results.

    Thanks again to one and all!
    Philip U.

    Sine scientia ars nihil est.

Similar Threads

  1. Q: Testing Exposure Meter Linearity Using ND Filters
    By Peter Collins in forum Lenses & Lens Accessories
    Replies: 12
    Last Post: 25-Sep-2014, 15:48
  2. Acros 4x5 Quickload blotches/anomaly
    By jvuokko in forum Darkroom: Film, Processing & Printing
    Replies: 0
    Last Post: 15-Feb-2013, 06:17
  3. Scanning Anomaly? Please help..?
    By l2oBiN in forum Digital Hardware
    Replies: 3
    Last Post: 15-Sep-2011, 10:06
  4. Testing old Kodalith development/exposure, suggestions?
    By Flea77 in forum Darkroom: Film, Processing & Printing
    Replies: 5
    Last Post: 8-Jun-2009, 17:24
  5. Testing VC grade changes w/o change in exposure
    By brian steinberger in forum Darkroom: Film, Processing & Printing
    Replies: 4
    Last Post: 3-Feb-2006, 07:42

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •