06b: Subtraction of Color

Hello everyone,

Please post the subtraction of color portion of our module six assignment below. The module can be found online at https://coloranddesign.community.uaf.edu/06-reverse-ground-theory-color-subtraction/.

As always, please let me know if you have any questions. Both of these projects look simple at first glance, but it can really be quite a challenge to get the exact color combinations right to get the optical effects to happen successfully.

Thank you!

Print Friendly, PDF & Email


  1. KatZZ


    Oy! This was a tough one. I actually tried it twice and failed horribly both times. With the first one, I think my two small boxed colors were too different to appear similar. Also, I used the wrong color of green for the background. It should have been lighter than darker than the smaller inner box.

    With my second attempt, I attempted to create two colors that were of a closer hue, but the background colors didn’t do much to help create similarity. Since I failed so horribly with my first attempt, I decided to try and recreate what the example was in the lesson. Not much better than the first attempt. Sigh. I understand the concept, but making it a reality is quite a challenge.

    1. Lara Lotze

      I hope you don’t mind, but I took your second example (blue/orange) and swapped the centers in photoshop. Your colors were pretty close to looking the same that way, still needs a little tweak but closer. You had orange tones on blue and blue tones on orange, but the intense orange is what will make the paler/toned down orange look more gray, and blue on blue will do the same there. Easy thing to switch. You had the right idea in the first set, but as you said the centers were too different. If you are starting with the outside boxes, maybe try with more yellow for the center colors, since that’s what green and orange share. Or if you are starting with center colors, maybe start with something closer and medium tone so you don’t have to work so hard to bring them together, if that makes sense.

    2. Sarah Griffen-Lotz

      Oh man, this is why I’m scared to try this one. It’s a lot more complicated to execute than part A. Working with acrylics instead of digitally with hex values is a lot slower of a process and involves a ton more guesswork. I feel that your second attempt was pretty successful considering all of that!

    3. I found this one really hard as well. I also think that maybe doing this assignment with a computer program might have been simpler concerning the variables in which paint contains. I couldn’t quite get the right layer of paint in the squares consistent enough to be correct. While I understand the concept, it was difficult doing this with paint. It was a fun assignment though!

  2. Sarah Griffen-Lotz


    This was definitely the trickiest part of this week’s assignments. One thing that really helped me was planning my colors out digitally, then mixing acrylic colors to match as I went. This part was tedious and I rinsed plenty of paint off my palette! Checking the brush I mixed color with against my computer screen was so helpful to get the right values. To make the first foreground green-blue color, I used about 3 parts bright aqua green to 1 part phthalo blue. To mix the second darker blue-green foreground color, I used what was left over from the last one and added a big glob of phthalo blue. For the yellow, I used yellow light hansa mixed with titanium white to desaturate it a little bit. For the red, I used cadmium red mixed with titanium white to desaturate that as well. The foreground colors were each heavily saturated, so the backgrounds had to balance that out.

    At the very end, the blue-green on the right dried too dark and the effect didn’t work at all. I re-taped those squares, re-mixed the old color, and added a few globs of titanium white and bright aqua green to brighten the color enough for the effect to work. It might not be perfect but it’s as close as I could manage.

    1. Ann

      Hey Sarah! I thought your paintings turned out beautifully! You did a great job in my opinion. I used circles for my project and upon viewing everyone else’s I hope that we were allowed the artistic freedom that I took! 🙂

    2. ahatfield2

      I think this turned out great – I actually wished I had looked at yours before doing mine. My red is WAY too dark – almost brown. I think if my red was a more similar shade to yours, I may have gotten a better result. Planning out your colors digitally and then matching them when mixing your paint was a great idea and definitely worked in your favor. Great job!!

      1. Sarah Griffen-Lotz

        Thanks! I would’ve been totally lost without checking potential colors first in Photoshop. Another thing I did was look at the colors in the Photoshop menu to see where they were, like the green being in the middle of green and blue, and I mixed paints from there.

  3. ahatfield2


    This assignment was definitely more of a challenge than the reserve ground theory one, in both understanding and execution. I watched the video a few times and feel like I did finally get a grasp on how to achieve the color subtraction effect. My plan was to use blue and teal for the center colors, and then a light yellow and dark red as the outer colors – getting the colors mixed correctly was a big challenge and I think that ultimately was a big issue. At first I thought I totally failed, however looking at the painting after it dried I think I am almost there – I definitely think the center colors look more similar then they do in the smaller swatch where they are isolated, but not similar enough to appear the exact same. I think my biggest challenge was that I couldn’t really determine which color (the blue or the teal) was darker, so even though I think I figured out which colors generally would work well in the background to shift where the centers appeared to fall on the color wheel, it was hard to determine which one needed to appear darker and which one needed to appear lighter in order to look more similar.

    1. Sarah Griffen-Lotz

      You were really close there, nice work! It’s cool how you landed on the same foreground colors as I did. The understanding was tough, I also had to watch the video a few times before it clicked. I agree that lightening the red would help make it work better.

    2. Elliot Hunker

      I’m not sure if it was the colors your were able to get, or if it’s the lighting you’ve got above your camera, but this painting really popped for me. The centers of these two swatches are remarkably different to the eye.

  4. Gabriel Ball

    The assignment this week definitely was a bit of a learning curve. I played around with the Paint program on my computer quite a bit to get a feel for how the color combinations were supposed to work, and I think I’ve got a good grasp on the concepts. Trying to translate that to paper was a bit tricky though. I had a hard time matching the colors that I created on my computer with my paint mixtures. The background colors were Yellow and Green. The box in the yellow rectangle is a light yellow-green. The box in the green rectangle is muddled green with more yellow mixed into it. I think it would have been more successful if the lighter foreground color was slightly more subdued.


    1. Bryana Angulo

      I mixed these two up. I will repost at the right places. This was a really tough concept to get to. I am going to need to practice more. I alkost got it, I think. I found that if i used the original small box color and addded colors to it based on the recommendations of the video that it made it easier. It really is interesting what color can do.

  5. This one was sooooo difficult. I tried to keep the colors the same but all the mixing I did made it so hard. I used tube colors for the blue and orange but the grey and bronze colors I had to mix. They seem much lighter and look the same when I placed them in the boxes of the foreground color. I don’t think it worked but I understand the concept. I think maybe this would have been better executed in a computer program where the colors don’t need mixed but as I understand the concept, I think it was a fun exercise and lesson on color.

  6. Lara Lotze

    For this one, I decided to plan my colors in photoshop in order to reduce the guesswork. I printed it out and tested my paint colors on the swatches (see here https://drive.google.com/file/d/1MyB8BQBqD8luG3tNs6N6Zlj09oZL5GTG/view?usp=sharing )

    After the really flat sky and sand in my other painting this week, I wanted some variety. The shadow/reddish orange on the yellow bird is the same color as the highlight orange on the red bird and I added red to that to make the shadow/reddish orange for the red bird. The two highlight oranges are the contrasting colors I was working with, but essentially I had two pairings with the shadow oranges too. It was fun to do a more whimsical piece this week. Mixing a little titanium white with my top layers helped acheive opacity, since I didn’t plan my background spacing as well as I should have.

    1. Chasity Joseph

      I absolutely love your birdies. I think you did really well and it was very smart to use the photo shop to test things out first. I think in the future I will probably do something along those lines too though I’m not tech savvy.

  7. Dawn Schlosser


    This one took me an extra try as well – you can see how I started painting over the center color on the green but ran out of paint. But I felt like I finally did do a good job with the color. I had to lighten and add a touch more pink to the color on the green side to get the visual match, but I’m still impressed with how close they look in person.

  8. https://docs.google.com/document/d/13R1sa3MoI0ZybGBz4GQJYp92S66jFqi5oGYZ58Oc83c

    This one was definitely more difficult with all the different variables to account for. I used a purple red and a pink red to try and get to look the same. To bring out the warm tones in the purple red I used a blue background that was a bit darker so the overall look is a bit brighter like the pink. On the pink red side I used a warm orange color so the blue hues popped. It was a bit difficult to darken the color up but that most likely is because I should have went over the color twice in the center for an opaque look. Unfortunately the paint I have isn’t meant to be opaque. It wasn’t horrible and I think I was mainly successful.


      I also had trouble with this at first because in my head, I was just reversing the foreground and background. I realized after I painted my first two that I needed to align the center and change the background.

  9. You can also borrow free audiobooks from the library. The Internet Archive offers 17,000 titles for free audiobooks online. These are great for kids who are trying to hone their comprehension skills before they start learning. Adults can also borrow free audiobooks through the Overdrive Sora App. After downloading the free audiobook, you can use it on any computer or mobile device.

Leave a Reply

Your email address will not be published. Required fields are marked *