Saturday, May 1, 2010

Acrylic Class Spring 2010

Week 3 – Cactus

It is always good to have a good reference photo or a detailed drawing when or both when you sit down to paint. As you all know I encourage my students to draw every chance they get , it give you more knowledge about your subject and the more information you have the better your painting will be, this will hold true even if you are painting more impressionistic almost to the point of abstract, it is your road map.

One of the things that doing a drawing helped me with was determining where my light was coming from and where it was going to. When I looked at it when I got it done, I realized that I put the lightest background in the wrong place remember we need dark to show light and conversely, we need light to show dark and we use this to our best advantage. In my painting, I planned it so I had light behind my darkest area and dark behind my lightest area.

I rough sketched where my cactus was going to be – not a lot of detail - then started out using gesso and a touch of yellow to create a soft area of light in the upper right hand third of my canvas painting over the sketch so I could get all of the background covered. Remember the Rule of Thirds, where the third lines intersect are your interest points so it is a good idea to get your viewers to the area you want them to look.

At the edges of the light area I used orange, sienna and gesso and roughly blended outward getting darker into the corners. To get darker, I used sienna, blue and purple – no white – this makes a very dark warm brown. I let this step dry.

When my background was dry I sketched in my cactus with a bit more detail so I knew where things were placed but not so detailed as to include petals or thorns, just major elements, I will do the detail with my brush.

I under painted the cactus with a mix of sap green with a touch of blue and purple to give me a medium dark color all of the pad and the stems of the blossoms with be painted with this color. The under painting for the blossoms I used the mud in my brush with white and yellow to make a light muddy yellow color. I used this color on the flowers as well as the tops of the buds. I let it dry before proceeding.

These next steps can be done in any order and it is okay to switch back and forth between them if you feel comfortable enough, as your painting skill improve, that kind of approach may serve you better keeping you from becoming so focused on one aspect that you neglect the other. Just keep it in mind.

We need to start highlighting and shadows. When I say highlights at this point, I'm not talking about the bright final highlights I'm talking about a color that is a shade or two lighter than what is already on the painting. There can be several layers of highlights, each just a bit lighter than the previous one. This helps to create depth and texture in the elements of your painting it's not something you can speed through and expect good results.

The overall color of the pad of the cactus while it may look green, it has a very yellowish tint to it so for the next layers of highlights I will be using my sap green and mixing in bits of yellow and touches of orange. The orange will slightly gray the green because it has red in it and red and green are compliments. Each time I will add more yellow and less green to build up my layers and I will use the dry brush technique to scumble the color on (scumble means to go in all directions). The highlights along the sunlit sides of the pad and buds will be mostly yellow with a touch of green and white. Remember to feather (lightly dry brush blend) the lighter color into the darker side to create a rounded edge.

The shadows are created using the sap green, blue and purple, the will make a very dark color. If you need it to be darker, add more blue and touches of purple. Start in the darkest areas and again using the dry brush technique, blend out from the dark area with your shadow color. It is important when using the dry brush technique to not only have a brush with little water and paint on it but to also very the pressure you use to apply the paint, to get those fine blended areas requires a very light touch.

To start the highlights on the flowers, it is going to take quick strokes and maybe a flat sable brush if you like. Use a mix of yellow with a touch of white and starting at the outside edge of the petals pull your brush towards the center and lift at the same time. If done right, you will have a bright edge and automatic shadows near the center. The bright highlights are just touches of white along the edges of some of the petals.

For the reddish leaves around and under the buds and flowers I used my napthol red with sienna, where they are in shadow, I added a touch of purple. Remember these leaves are going around a rounded object so your strokes need to reflect that roundness.

Finishing the cactus: Across the face of the pad there are lines – not straight lines BTW – where the thorns attach, there are slight ridges if you are wanting to do some detail. Mix a highlight color that is slightly lighter then the color you have for the flat part of the pad and with a very dry brush and a very light touch, scrub in this color in an uneven diagonal line across the face of the pad. Do this for each row, rinse your brush and mix a color just darker than the color of the pad and with the same light touch and dry brush, add a shadow next to the color you just put down. This will be the line where you will put your thorns, the important thing is they are not straight even lines and it is a very soft blend.

In some of the shadow areas you can brush in a mix of blue, purple and a touch of white to create a reflected highlight and dry brush it in to give some light into the dark areas. The rest is up to you. Do as much or as little as you want to finish looking for areas where you can add light or dark, don't forget shadows from the flowers, buds and thorns.

Next week we will do some basic shapes so no reference picts this time. I am noticing people struggling with getting shadows, highlights and mid tones to work for them so this will be a bit of a review and practice some blending techniques.

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