The film developer and water mixture is what you'll use to develop your film negatives in the tank. You need enough of the mixture to completely fill the tank. The exact amount you should mix depends on the size of your film tank, but it's usually around 16 fluid ounces (470mL) of film developer and 16 fluid ounces (470mL) of water. Mix the developer and water in a metal or plastic container, not in the film tank. You don't need to stir the developer and water together. You can find film developer online or at your local photography store. The temperature of the film developer and water mixture determines how long your film will need to develop for. Once you know the mixture's temperature, refer to the manufacturer's instructions for your film to see how long it will need to develop. Every kind of film is different, so it's important that you read the directions that came with yours. If you can't find the developing times for your brand of film, try looking them up online. Film typically needs 8.5 to 11 minutes to develop. Pull the uppermost plastic lid on the tank off to reveal the funnel-shaped hole underneath. Do not unscrew the larger lid that's sealing the tank shut. Pour the developer and water mixture directly into the hole in the lid. Once all of the mixture is in the tank, cover the hole with the plastic lid and immediately set a timer for however long the film needs to develop. Agitating the film means turning the tank over continuously with your hands to help spread the developer around. To agitate your film correctly, you'll need to use the following schedule: First minute of developing: Agitate the film for 30 seconds. Then, place the tank on a flat surface for 20 seconds. After 20 seconds, agitate the film for the remaining 10 seconds of the first minute. Second minute of developing: Let the film tank rest on a flat surface for 50 seconds. Then, agitate the film for the last 10 seconds of the second minute. Subsequent minutes of developing: Repeat the same agitation and rest times you used in the second minute of developing for every minute until the film is finished developing. Take the uppermost plastic lid off the tank so you can empty out the mixture. You can pour the mixture down a sink drain. Stop bath is a liquid chemical mixture that stops film from developing any further. Once your tank is filled with stop bath, agitate it for 30 seconds to help the mixture spread throughout the tank. You can find stop bath online or at your local photography store. Fixer is the last chemical used in the development process. It helps stabilize your film so it can be exposed to light without getting ruined. Once your film tank is filled with fixer, seal it and follow the same agitation schedule you used for the developer mixture. The exact number of minutes you should leave the fixer in the tank depends on the kind of film you're using, but it's typically between 3-5 minutes. You can find film fixer online or at your local photography store.

Summary: Turn the lights on and mix 1 part film developer with 1 part water. Use a thermometer to measure the temperature of the mixture. Pour the mixture into the film tank and set a timer. Agitate the film periodically as it develops. Pour the developer mixture out of the film tank. Fill the tank with stop bath and agitate it for 30 seconds. Pour out the stop bath and fill the tank with fixer.

If your parents have different Rh factors (or if they are both positive and you want to know for sure that you are also positive), you can request a blood typing test. This outpatient procedure is fast and should not be very painful. You can go home afterwards. A nurse or physician will clean a spot on your inner elbow or wrist with an antiseptic towelette. He/She will locate an easily accessible vein in this area. After wrapping a tourniquet around your upper arm to pool the blood, he/she will stick your vein with a needle. The needle is usually connected to a syringe, which removes your blood. Once he/she has taken enough blood, he/she will take out the needle and gently press the injection site with a sterile swab. You will then receive a bandage. Afterwards, the nurse will label your sample and send it to a lab for testing. Doctors test children's blood through the back of their hands. If you feel like you might pass out, tell the medical professional. He/She can help you recline. You might feel a prick, sting, or mild pain when your nurse sticks you. After the test, you might bruise at the puncture site. This pain should not last long. At the laboratory, a technician will test your sample for its Rh factor. He/She will combine a sample of your blood with an anti-Rh serum. If your cells clot, you have Rh+. On the other hand, if your blood cells do not stick together, you are Rh-. It is likely that the lab will run tests to determine your ABO blood type as well during this time. Record your blood type in a safe place and share this information with your emergency contacts. You will need this information if you require a blood transfusion or organ transplants. Additionally, if you are or plan to be pregnant, knowing your Rh factor is essential. If you are female and Rh-, you will need to have your partner test his Rh factor. If you are Rh- and he is Rh+, you can experience Rh incompatibility. This means that if your baby inherits his father's Rh+, your antibodies can attack the baby's red blood cells. This can cause extreme anemia and possible death for the baby. During your pregnancy, if you are Rh-, you will take blood tests to see whether your body is producing antibodies against Rh+ blood. The first will happen in your first trimester and the second will occur when you are 28 weeks pregnant. If no antibodies have developed, you will receive a shot of Rh immune globulin. This shot will prevent your body from producing harmful antibodies against your child. If your body has produced antibodies against Rh+ blood, you will not receive an immune globulin shot. Instead, doctors will keep a close eye on your baby as he/she develops. Either before or after his/her birth, your child might receive a blood transfusion. Once your baby is born, doctors can test his/her Rh factor. If your baby shares your Rh factor, you will need no further treatment. If you are Rh- negative, however, and your baby is Rh+, you must receive another immune globulin shot.
Summary: Ask your doctor for a blood type test. Take blood typing test. Test blood sample. Recognize the importance of your results. Be aware of your pregnancy risks.