Author Archives: Morgan Flanagan Popko

The Tragedy with Additive and Subtractive Color

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Being a student of Graphic Design at Penn State, I am constantly using both additive and subtractive color mixing techniques when creating my projects. The medium required for each project determines the type of color mixing used. Additive color mixing is mostly used on computer and television monitors. This process mixes colors of light to produce the image we see on a screen or other electronic device. The three primary colors of this process are red, green, and blue. These colors mix together to form secondary colors which are cyan, magenta, and yellow. When all three primary light colors are present, the result is white, and when all light is absent the result is black. These three colors set the foundation for the endless combinations of colors seen on a computer screen everyday. Subtractive color mixing is an extremely different process and requires a different medium to create the spectrum of colors. This process combines different colors of ink or paint, using printers or manual labor, to create images we see on paper or canvases. The three primary colors of this process are cyan, magenta, and yellow, which are commonly found in ink cartridges. The three secondary colors of subtractive color mixing are red, green, and blue. These colors combine to produce the wide variety of pigments seen in printed and painted designs.
One important restriction regarding subtractive color mixing is that when mixing the different pigments, the colors are not perfectly created, because there is a portion of light from the newly subtracted color that is reflected. This creates a slightly darker and desaturated pigment when compared to the same color in the additive color spectrum. Also, some printers unable to create certain colors that are seen on a computer screen. This can cause issues when transferring projects from additive color to subtractive color to print out a design. Unfortunately during this past semester, I learned this lesson the hard way when working on one of my projects.
My photos were uploaded and my design was perfected, just in time for the deadline of my second project. I felt confident with the final design and was excited to see a printed out version of the piece. I went to Staples to print out my final 15 by 20 inch poster and my sense of accomplishment was crushed. The colors of the poster were dull and slightly off hue, as opposed to the vibrant colors I saw on my computer screen. I was confused and tried to understand possible reasons for the problem.
Fortunately, in the same week this had occurred, we were learning about additive and subtractive color in our perception class. Once I realized the two different color modes, I understood where I went wrong; my project was constructed and edited in the RGB color mode in Photoshop. This meant that the program was using the additive color mixing process to create the colors I saw on my screen; however, printers use the subtractive color mixing process to create the tangible designs. As I stated above, some of the colors that are seen in the additive color spectrum are not produced or poorly reproduced in the subtractive color spectrum. Therefore, the printer desaturated the colors I saw on my computer screen, producing a dull version of my project. I was forced to recreate my design in the correct color mode in Photoshop to allow for optimum printing results. If I had known how different my project would have resulted, I would have paid more attention to color mode I used in Photoshop. The difference between additive and subtractive color is one of the most important lessons to learn as a Graphic Design student, and I will use this knowledge in my future projects.

Vision Impairment and Astigmatisms

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             Impaired vision can be defined as the functional limitation of an eye, eyes, or visual system. It has become more prevalent among individuals over the past few centuries. Research from the Arlene R. Gordon Research Institute shows that the number of individuals with impaired vision recorded in 2011 is predicted to double by the year 2020 (Gordon). Many forms of vision impairment affect my family on a daily basis. My mother has worn corrective lenses since third grade to assist with her myopia or nearsighted vision impairment. However, her vision is also distorted by a condition known as an astigmatism, which causes one or more refractive surfaces on the eye to curve. She recently visited an eye doctor to renew her corrective lens prescription and found the results to be somewhat unexpected.

            She arrived at the eye doctor and was prepped for an eye examination. When the doctor produced the results, my mother was extremely surprised. Relative to the general population, she had an exceptionally mild case of myopia; however, her astigmatism was so severe that it caused her vision to rank closely to that of a legally blind individual. The doctor prescribed her a corrective lens that would best fit her needs; however, her vision still remains slightly impaired. These results opened my eyes to the serious effects astigmatism can have on an individual’s vision.

            Astigmatism is an optical condition that blurs an individual’s vision due to the irregular curvature of the lens and/or cornea of the eye. This curvature restricts the lens or cornea from correctly focusing an object on the back of the retina to create a sharp image. With the addition of nearsighted vision impairment, this defect can cause extreme image distortion for an individual such as my mother. Nearsighted vision impairment is a condition that allows an individual to see close objects clearly, but objects in the distance are blurred or distorted. This is caused by an irregularly elongated eye shape that places the point of focus, which would normally lie on the retina, slightly in front of the retina. This newly positioned focal point creates impaired images for objects that are at a distance. Although this condition was not a large factor in my mother’s case, it can cause extreme issues for many people depending on the severity of the impairment.

            After hearing my mother’s experience and learning about the various conditions that contribute to vision impairment, I now understand how two individual vision cases can be extremely different from one another. My mother’s vision was distorted mostly because of an astigmatism; however, another individual may have a severe case of myopia that contributes to their vision impairment. The combinations are endless regarding the different defects in the eye and the type of corrective treatment needed to assist an individual with their vision impairment.

Works Cited:

Gordon, Arlene R. “Prevalence of Vision Impairment.” Lighthouse International.  n. page. Web. 18 Mar. 2014. http://www.lighthouse.org/research/statistics-on-vision-impairment/prevalence-of-vision-impairment/.