SIMPLE IS AS SIMPLE DOES

Even with careful exposure, you might notice that your results are often unexpected, inconsistent, or even undesireable.  You might suspect the development of the film, even if you don't do the processing yourself.  Just because a professional or an expensive machine does the processing does not mean that you're getting the best results.  Fortunately, there are a few simple tests that you can make to assure that your film exposure matches the processing technique of the shop that handles your film.  Since this is a simplified approach, the only pieces of testing equipment you will need is a Kodak grey card and an inexpensive filter -- a Kodak ND 0.1 (neutral density) 3x3 inch gelatin filter.  These are available through most camera shops, and are useful for more things than just this test. The tests are relatively simple, but you may find that you need to repeat them several times -- depending on your situation.  

1. Since the processing is fixed by your lab, you can make a test to get the best exposure for their processing methods and your equipment.

• A. Set up the grey card in a sunny spot with no reflections or shadows falling on it.  Set the lens at infinity but move close enough so that the grey card fills the frame of the viewfinder.  Use whatever metering method you like, at whatever ISO film speed you normally use and make an exposure of the card.  
• B. Now cover the lens with a lens cap or opaque cloth and make another exposure.  This will produce a clear section on the negative right next to the grey card exposure.
• C. Expose the remainder of the film normally.  This keeps your test exposures down to a minimum.
• D. When you are done with the roll, have it processed normally.
• E. When the negatives (and prints) are returned, find the negatives of your two test exposures.
• F. Cut the gelatin filter into nine one-inch squares.
• G. Stack seven of the filter squares together -- this stack will create a 0.7 ND filter.
• H. Place the filter stack under the "clear" exposure, right next to the grey card exposure.  
• I. Hold up the negative with the filter stack and look through it.  The densities of the grey card exposure and the "clear" exposure/filter stack should appear the same.  This will be easier to do if you place a white piece of paper under the negative or hold the negatives up in front of a white wall.  
• J. If the grey card exposure is darker than the "clear" exposure with the filters, you are over-exposing your film (for the lab's processing).  On the next roll of film increase the ISO film speed one notch and retest.  For example, if your original roll of film was exposed at ISO 100, shoot the next roll at ISO 125.  Keep re-testing until the grey card exposure matches the "clear" exposure/filter stack.
• K. If the grey card exposure is lighter than the "clear" exposure with the filters, you are under-exposing your film (for the lab's processing).  On the next roll of film decrease the ISO film speed one notch and retest.  For example, if you original roll of film was exposed at ISO 100, shoot the next roll at ISO 80.  Keep re-testing until the grey card exposure matches the "clear" exposure/filter stack.
• L. Even when you get a match, it's a good idea to re-run the test every once in a while.  You'll actually be testing the consistency of the lab.  Some are more consistent than others.

2.  You'll need to rerun this test, for each film that you use, or if you change processing labs.

FRONT DESK.

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