Page 1 of 3 123 LastLast
Results 1 to 10 of 23

Thread: Film Test Results

  1. #1

    Join Date
    Sep 2006
    Location
    The Beach, FL
    Posts
    106

    Film Test Results

    I need some helping interpreting my film speed test. I have attached 3 images from the N (normal) development roll of 120 film (Delta 100). The first image is Zone V, the second Zone IV, and the third Zone III. I think I made a couple mistakes and I may need to reshoot this. Mainly because the light was not even and I should have probably kept everything in focus. Anyway perhaps the more experienced here can help me decipher this. I metered from the grey card that is in the image and developed normally. I also developed the same exposures on 2 separate rolls at N-1 and N+1. Did I make a mistake by metering off of the grey card? Should I have metered for zone III or some other zone? The one thing I have learned from this so far is the affect of N-1 and N+1.... that is good stuff. Thanks.

  2. #2

    Join Date
    Feb 2005
    Posts
    2,955

    Re: Film Test Results

    For a film speed test you should shoot a blank wall or grey card. Don't consider plus or minus development until you have established your personal EI for your equipment and process.

    See the following link:

    http://www.jerryo.com/formula/z_speedtest.html

  3. #3

    Join Date
    Sep 2006
    Location
    The Beach, FL
    Posts
    106

    Re: Film Test Results

    Ron,
    are you saying I should have filled the lens with the grey card? There is one in the scene I shot as a reference. Also, this is the normal development, I also did N+1 and N-1, but that is not included here and was just done to get a feel for what can be done. Thanks for link.

  4. #4

    Join Date
    Nov 2006
    Location
    Mount Vernon, Virginia
    Posts
    200

    Re: Film Test Results

    Quote Originally Posted by Tony Flora View Post
    Ron,
    are you saying I should have filled the lens with the grey card? There is one in the scene I shot as a reference. Also, this is the normal development, I also did N+1 and N-1, but that is not included here and was just done to get a feel for what can be done. Thanks for link.
    Yes. Fill the frame, and make sure the grey card is completely out of focus as well.

  5. #5

    Join Date
    Apr 2008
    Location
    Jamul, CA
    Posts
    100

    Re: Film Test Results

    Quote Originally Posted by Ron Marshall View Post
    For a film speed test you should shoot a blank wall or grey card. Don't consider plus or minus development until you have established your personal EI for your equipment and process.

    See the following link:

    http://www.jerryo.com/formula/z_speedtest.html
    Good info. I'm just getting ready to jump back into 4x5 after many years.

  6. #6

    Re: Film Test Results

    For a film test speed there is no reason the gray card has to be out of focus, so long as there wasn't enough bellows draw for that to be a factor.

  7. #7

    Join Date
    Jun 2008
    Location
    Nashville, TN
    Posts
    314

    Re: Film Test Results

    Basically what you are trying to do is find out how much developing time it takes to build a certain density level at a certain metered zone. This will vary depending on what zone you are testing as the higher zones (V thru XV+) build density for a longer period of time during development than the lower zones (I, II, III, IV). You definitely need even lighting and you would be better off just shooting the gray card, but do not shoot it with an extension longer than the focal length of your lens that would put you into macro compensation.

    Steve Simmons has a good article on this:
    http://www.viewcamera.com/pdf/2006/V...;20Started.pdf

    Also I have a few good links on my links page:
    http://willwilson.com/articles.html
    Will Wilson
    www.willwilson.com

  8. #8

    Join Date
    Sep 2003
    Location
    Massachusetts USA
    Posts
    8,476

    Re: Film Test Results

    Another way, is to shoot a real scene, in daylight, with people in it, and with real subjects that are in light and shadow.

    If you can't find a "real" person, you can always use... yourself. Here's a test shot I did when trying TMAX at ISO 200, in PyroCat HD. I tripped the shutter with a long bulb release.

    As you can see, its easy to figure out which film speed/developer combination to use, when you know right away how things are going to work in "real-world" situations. You can tell right away, whether the result will "feel like light", which to me is a tangible and worthy goal. It's what I was taught a long while back, and I still like the approach.

    Tossing in some black and grey fabrics in sun and shade, as well as a dark cloth, film holder slide, pumpkin, porcelain pot, green leaves, black socks, and a plastic bottle, help lend credence to the final result.

    Like so many others, I found that TMY works best for me at 1/2 the stated film speed - just as Tri-X was, back in 1971 when I first tested it in HC-110, getting the same results as Fred and Ansel. One would certainly hope so.

    It is reassuring to discover that my agitation is normal, my thermometer is calibrated, and my water is... not too contaminated.

  9. #9
    ic-racer's Avatar
    Join Date
    Feb 2007
    Posts
    6,729

    Re: Film Test Results

    The simplest way to determine your EI is to meter a uniform target and expose it to Zone I at varying exposure indexes.

    Process the film at any guess at what your development time for "N" might be (your Zone I density won't change that much if your development time is not 'correct.').

    Look at the resulting negatives and choose the one that shows the target to be 0.1 log denser than the clear film base. (That's 1/3 of a stop).

    How to you make the determination of 0.1??

    1) Use a densitometer (best)
    2) Use your exposure meter and meter through the negatives and pick the one that blocks light 1/3 of a stop more than a clear frame
    3) Send your negative strips to someone who has a densitometer and have them e-mail you the results.
    4) Guess. Sandwich two pieces of clear film base together and match that to the target negatives.

  10. #10
    Peter De Smidt's Avatar
    Join Date
    Jan 2001
    Location
    Fond du Lac, WI, USA
    Posts
    8,944

    Re: Film Test Results

    Ic-racer gives good advice, with the caveat that your Zone I density be at least .1 above film base plus fog. Personally, I prefer the shadow separation of Zone I being .15 to .2 above fb+f. After you determine your film speed, i.e. how much exposure to get a proper zone I density, you then need to determine your development times. An easy way to do this is to set your meter for the speed your first test achieved. You then exposure a gray card and place it on zone VIII. Use the same development that you used for the film speed test, and read the density. If you have a condensor enlarger, a good target is 1.2 above fb+f. With a diffusion enlarger, zone VIII at 1.3 above fb+f is a better measure. If you're densities aren't close to what I listed, you can then adjust development time to get them in the ball park. Btw., I'd be happy to read negative densities for you. PM me if you want me to do so.

Similar Threads

  1. Inconsistent results with Zone tests
    By Don Wallace in forum Darkroom: Film, Processing & Printing
    Replies: 9
    Last Post: 25-Feb-2007, 09:58
  2. Some lightfastness test results
    By paulr in forum Darkroom: Film, Processing & Printing
    Replies: 5
    Last Post: 29-Aug-2006, 09:48
  3. How to test film for in-camera colour separations
    By David Nash in forum Darkroom: Film, Processing & Printing
    Replies: 6
    Last Post: 11-Mar-2005, 23:23
  4. silliest question ever: how to load sheet film
    By David Haardt in forum Style & Technique
    Replies: 13
    Last Post: 7-Jun-2001, 17:55
  5. Film plane alignment
    By Dave Schneidr in forum Cameras & Camera Accessories
    Replies: 4
    Last Post: 15-Nov-1999, 20:17

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
  •