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Processing Step-by-Step
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Processing Angiograms

Janice Clifton, CRA COT
Seattle, Washington

Paul R. Montague, CRA FOPS
Iowa City, Iowa

Photographic Illustrations by
Peter Buch, CRA
Buffalo, New York


Loading the processing reel is a skill that must be mastered for successful film processing. Ever hear the saying, "I could do that with my eyes closed"? Well, in this case, it's a necessity.

There are two sides to the film: The emulsion side and the base side. When the film is rolled on it's spool inside the cassette, the emulsion side of the film is the inner side, the side which faces the camera lens when loaded for picture taking. The emulsion side is the side that will contain the image and the only side that is acted upon by the developer. Anything which comes in contact with the emulsion side of the film during processing will hinder proper development of the image. If the emulsion side of the film is touched by oily fingers, the finger print may be developed into the negative.

Processing reels are a continuous spiral into which the film is loaded, preventing the film from touching itself during processing. Mishandling of the film or improper loading of the reels may damage part or all of the angiogram.

The key to perfection in loading spiral reels is practice. Check with a local professional photo supply store to see if they have any outdated film which is about to be discarded. This makes perfect practice film! Once a roll of film has been incorrectly loaded onto a reel, small dents in the film edges make it very difficult to load correctly the second time. Consequently, a sizeable supply of test film will be required before you are ready to get on with the real (or reel) thing. Practice in the light first. When the technique has been perfected, try again with you eyes closed. Only peek when you feel something going wrong. Then try with the lights out. And finally, if you are going to load film in a changing bag, practice loading film in the bag until the technique is perfected.

When practicing, load the film onto the reel then unload it. Examine the film as you pull it slowly from the reel, looking for indentations on the edges of the film which indicate the film slipped out of the spiral, or small half-moon shaped creases in the center of the film indicating that the film was kinked during loading.

And away we go!

If you are using a changing bag, place the film cassette, the can opener, the scissors, the processing reel, the tank, and the tank lid in the bag and zip it shut. If you are in a darkroom, make sure these things are easily accessible on the counter.

Using the blunt end of the can opener, pry open the end of the film cassette. Opening the end opposite the spool extension is easiest. Remove the film and the spool from the cassette. Remember not to touch the inner surface (emulsion side) of the film with your fingers. This may be difficult it you have just dropped the spool of film on the floor and are now more concerned with finding it in total darkness than with which side you touch, but do the best you can.


There is an irregular shaped tab on the end of the film. This is the end that threaded onto the take-up spool in the camera. Cut it off with the scissors. If you're not too handy with scissors, wait until the bleeding stops before continuing.

The reel loading procedure is a little different between plastic and metal reels. If you're using plastic reels, skip to the plastic reels paragraph.

Metal Reels. Hold the film in one hand so that it unwinds off the top of the spool. Unwind a few inches and hold the end of the film between the thumb and forefinger allowing the spool fall from the hand. Apply a slight amount of pressure between the thumb and forefinger to cause the film to bow upward.


Hold the metal reel in the other hand with the end of the spiral point toward the film. If you are doing this in the light for the first time, find the end of the spiral by looking at it, then practice finding it in the dark.

With the film bowed slightly, insert the end of the film directly to the center of the reel and place it under the clip or wire to hold it firmly in place. Maintaining slight pressure on the sides of the film, wind the film onto the reel, from the inside out by rotating the reel in a circle, away from the film. Continue until all of the film has been wound onto the reel.

Do not force the film onto the reel! It should flow onto the reel evenly and smoothly. Loading reels is something that is done by touch. If you feel anything irregular, STOP, unwind the film slightly and continue.

Plastic Reels. Plastic reels load from the outside in. Place the end of the film in the outer most edge of the groove in the reel until the film catches. The opposing edges of the reel are twisted back and forth, pulling the film onto the reel.


Plastic and metal… At the end of the film, trim off the spool with the scissors. Place the reel into the can and cover it with the light-tight lid. Once the lid is on, all other steps can be performed in the light.

Consistency is an extremely important component in obtaining repeatable results when processing film. Whether the timer is started before or after the chemistry is poured into the processing tank is of little importance providing it is always done in the same way. Small changes in the temperature of the developer, the time the film is in the developer, the frequency and method of agitation when the film is in the developer, and a wide variety of other factors can make dramatic changes in the density and contrast of the final image. Use the procedures outlined here as guidelines. Over time you will develop techniques that you are comfortable with which produce good results. If you are not consistent in your method, adjustments to fine tune the quality of your negatives will be difficult or impossible.

Agitation is required during processing to keep fresh developer near the surface of the film. Without agitation, especially in the developer development will be uneven, often producing bars of alternating light and dark areas across the film. Techniques for agitation differ between metal and plastic reels.

Metal reels are usually agitated by grasping the tank in the palm of the hand with the palm facing downward, then, in about a one-second movement, rotating the hand so the palm faces upward. This is immediately followed by another one-second movement rotating the hand so the palm is facing downward once again. These two-second agitation cycles are generally performed three times every thirty seconds, providing about six seconds of agitation for every thirty second interval.


Plastic reels are usually agitated by grasping the plastic spindle which protrudes from the top of the tank and twisting it back and forth slowly. This rotational agitation is performed for about six seconds every thirty seconds.

At the end of each agitation cycle, the tank is rapped lightly on the counter top or sink two or three times. This dislodges any air bubbles which might be clinging to the film as a result of agitation.

Developer can be used once and discarded, or can be saved and reused. If developer is reused, pour it back into the developer container after processing film. With each successive roll of film that is processed the developer becomes slightly less active. This mandates an increase in development time as the developer ages to compensate for the lower activity. The developer comes with a chart that outlines the amount of time to add as the developer is used.

Greater consistency can generally be obtained by using the developer once and discarding it. The exception can be found in larger processing labs where tanks which hold 3½ to 25 gallons of developer are used. The developer is usually replenished by adding a special developer replenisher which replaces the used chemicals in the developer. Accurate replenishment requires the use of a densitometer to measure the activity of the developer, and is beyond the scope of this text.

Processing times vary depending upon the exact chemistry chosen, the film type, and the light output of the fundus camera. The following times and temperatures should be a good starting point using the chemistry given as an example in the chemistry section.







HC-110 Dilution A

70o ± ½o F.

5 minutes

Stop Bath

Kodak Indicator Stop Bath

70o ± 3o

30 seconds


Kodak Rapid Fix

70o ± 3o

6 minutes


Running Water

70o ± 3o

30 seconds

Hypo Clear

Hustler Rapid Bath

70o ± 3o

30 seconds


Running Water

70o ± 3o

5 mintues

Wetting Agent

Kodak Photo Flo

70o ± 3o

30 seconds


Not over 120o F.


Steps for processing film

  1. Load the film onto the reel, and place the lid on the tank.
  2. Place enough developer to fill the processing tank in a small open-mouthed container. If you are processing only one roll of film in a two-reel tank, place an empty reel in the tank to fill the vacant space, and still use enough developer to fill the tank completely.
  3. Check the temperature of the developer. Raise or lower the temperature by placing the open-mouthed container in warm or cool water until the proper temperature is reached (70o F. for our example).
  4. Set the development time plus 15 seconds on the GraLab timer (5 minutes 15 seconds for our example). The extra 15 seconds allows you to start the time, then prepare to pour the developer into the tank after the 15 seconds has expired.
  5. Start the timer.
  6. When the extra 15 seconds has expired, begin pouring the developer into the tank through the light-tight hole in the lid of the can.
  7. Agitate the film continuously for the first 30 seconds. Metal reels are rocked in the hand and plastic reels are rotated as described above.
  8. Rap the tank once or twice on the counter top or sink to dislodge air bubbles. Gentle taps are sufficient. Don't dent the sink or crack the counter top.
  9. During development, agitate the film for five or six seconds every thirty seconds.
  10. Fifteen seconds before time expires, begin pouring the developer from the tank.
  11. Pour the stop bath into the tank, agitate for 30 seconds, and pour the stop bath out. The 30 second time for the stop bath is not critical.
  12. Pour the fixer into the tank and set the timer for the fixer time (6 minutes for our example). Agitate continuously for the first 30 seconds then six seconds every minute thereafter.
  13. Pour the fixer from the tank. Fixer is almost always saved for reuse.
  14. At this point the top may be removed from the tank. The film is no longer sensitive to light.
  15. Rinse under running water for 30 seconds. 
  16. Pour in the hypo clearing agent. Agitate continuously for 30 seconds and discard the used hypo clearing agent.
  17. Rinse under running water for 5 minutes.
  18. Pour in wetting agent (Photo Flo in our example). Do not agitate! Wetting agents create foam when agitated.
  19. Hang film to dry, placing a clothes pin or weighted clip at the bottom of the film to prevent curling.

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