Visual Art Cheat Sheet

• The purpose of visual observational art is conveying, not the object in its fullness in abstract space, but the concrete image available to the visual field based on interactions of light with that object
  • The image the object has on the visual field is based on: ($a$) bottom-up emergent features based on the behavior of light, and ($b$) top-down imposed interpretations from perception that relate to the conception of the object
    • The following skew towards being under $a$: tonal value (a.k.a., value or shade) and hue (i.e., color / colour)
    • The following skew towards being under $b$: contour or edge, and form or shape
  • The place and time of an object being drawn changes together with the place and time of the act of drawing.
    • Location and time affect the affordances which allow it to produce given images on the visual field. Since drawing is not instant, but an activity, despite attempting to capture an object fixed in time and place, it necessarily creates a fictional version of the object. Even a drawing from observation requires an element of fiction, or perhaps more accurately of engaging the imagination.
      • In particular, the features of the image that most require imagination are those most likely to change over time or relative to placement: the bottom-up emergent features (typically value and hue). That is, all that falls under $a$.
        • The top-down features nonetheless are contingent on these to some extent insofar as they inform chosen top-down imposed conceptual structure, and so the effect cascades to all features of the image including $b$.
  • Top-down imposed interpretation of visual sense-data, i.e. visual perception, as in $a$, comes in two forms: ($c$) the treatment and use of what can be seen in our conception of the object, and ($d$) the inference of what is not seen based on that conception.
    • $c$ are edges and shape, the latter being $2D$ shapes in particular given the visual field.
      • Thus, one draws edge and shape together insofar as they divide the space up for us to organize visual sense-data like hue and value. Edge and shape organize images.
    • $d$ is form, which involves an inferred sense of depth or voluminous presence
      • Thus, one does not draw form, but suggests it with other image features (e.g., value and hue). One must draw neglecting depth yet indirectly maintaining it. Form suggests there is more to an image.
    • One could say that while edge and shape are ultimately the responsibility of the artist, form is ultimately the responsibility of the viewer. Nonetheless, to convey form, an artist must understand the spatial concepts of most viewers.

• Observational contour drawing

  • Observational contour drawing can use a few steps then: (1) observe the object to be drawn, (2) digest outermost to innermost visible horizontal or diagonal edges of the object, (3) project the direction and curvature of that edge as a line onto the respective surface, and (4) follow the continually evolving pattern(s) of the line or upcoming lines. Make sure to loop this process if necessary.
    • Before step #2 and after step #1 in the first iteration, take note of shapes that you anticipate will be troublesome in order to practice that shape separately prior to continuing the rest of the drawing. This is called iterative sketching.
    • When engaging in this, it helps to ==remind yourself that what you are looking at is the image of the object on your visual field==, rather than the object itself as a whole.
    • Long horizontal or diagonal lines are recommended starting spots on an image.
    • On step #3, “projecting” the line means you have to imagine the movement or motion that corresponds to the line (or your eyes that follow it).
      • To scale the image or object down or up while drawing, simply #gesture at drawing the given line a few times while feeling the constraints of the surface you are using, and only draw the line once you’re confident in your #intuition. This takes practice, as it is a heuristic.
  • The dimensions of the surface one is drawing on, and its orientation, affect the degree rotation of the lines drawn on it. Hence, one must always draw a line relative to the frame of the surface one is using when trying to convey its observed orientation (this is called the framing principle of linear degrees).
    • ==Straight horizontal or vertical lines must be parallel to the straight horizontal or vertical sides–respectively–of the surface being drawn on==.
    • Attempt to correct for your tendency to skew a line based on your handedness (i.e., based on your lateral bias) when trying to make any straight line.
  • The constraints of the dimensions and orientation of the surface drawn on can also be made use of to loosely analyze the geometry (more specifically the symmetry) of one’s drawing, as placing horizontal or vertical lines on that surface or the drawing itself (as long as the line placements obey the framing principle of linear degrees) allow understanding the relative orientation and position of the drawing on that surface as well as its symmetry.
    • The placed horizontal line in this scenario that allows analyzing what one is drawing relative to the surface one is drawing on is called the level.
    • The placed vertical line in this scenario that allows analyzing what one is drawing relative to the surface one is drawing on is called the plumbline.
  • For drawing objects or images of them with complex form, do a preliminary drawing or sketch called an underdrawing that simplifies that form’s shapes. To do this you can ($e$) reduce the number of lines needed to convey basic motion or movement of a given shape, and ($f$) decompose the complex shape of the form into a minimal number of the largest shapes needed to convey that form’s shape.
  • Even better for objects or images of objects with complex form, is straightening out bumpy lines or lines with major curvature–especially with complex or winding curvature–at the edges of an object or an image of an object, such that only the essential #points of radical change in line direction or position (the inflection points) at the edge of the object or its image are conveyed. The details and smaller developments of the edge line can be filled out later. This is especially helpful for asymmetric objects or images of them.
    • A heuristic for only conveying the essential points of change among lines in a shape is to visualize the application of wrapping paper around the object being drawn, such that straight lines emerge due to tension from resistance at certain corners or sides of the object.
  • Use sighting, i.e. ==finding “invisible“ (i.e., perceived) straight lines between points of or on an object, called sight lines, with the use of a straight, elongated object in the foreground of your visual field as a guide==. Typically, this involves using a pencil, or whatever styli one is using to draw, to find and measure invisible lines (distances) between points on the given object.
    • This allows the application of a mental plumbline or level to the object being drawn, to get a good sense of line orientation or rotation, so typically the #styli used for sighting is kept vertical or horizontal relative to the ground you, as an artist, stand on.

• Rendering

  • To render a drawing is to apply tonal value to it, and tonal value is the spectrum from pigment that reflects more light to pigment that absorb more light, in essence going from whitest to blackest.
    • This means that ==anything with a discernible hue must reflect at least some light==.
    • Darkening a hue can be as simple as adding more #black pigment to that hue, while lightening a hue can be as simple as adding more #white pigment to that hue.
  • When rendering an observational drawing, squint at the object you are drawing to create blur and thereby eliminate crisp edges and details. This allows the hues and tonal values of the image to stand out or “pop out” in visual perception (refer to 20250120145317-Observing_Tonal_Value_for_Visual_Art).
  • When rendering through the use of gradual layered scribbling and build-up of lines (which is typically what happens with a restricted pinpoint styli, such as a pen or pencil), the conveying of tonal value of an object or image and the conveying of its #texture are inextricably bound in the act.
  • There are three kinds of tonal value: ($g$) local tonal value, which can be seen as the “default” value of the given object (how light or dark it is proportional to its hue under ambient light, which can vary); ($h$) transitional tonal value or middle tonal value, which provides transition between light and dark value shapes (this is typically the fill lights in objects’ shadows); ($i$) shadow tonal value, which is the value of the places receiving the least amount of light on the object or in the image.
    • The last type, shadow tonal value, itself comes in three kinds: ($j$) directional shadow, which is that shadow produced, usually on the surface of an object, by that part facing away–or being at a direction opposed–to the source of the light (i.e., it is related to direction relative to the trajectory of light); ($k$) cast shadow, which is that shadow projected onto a separate but adjacent surface by an object due to its occlusion of, and reflection of, that light on its own surface (i.e., it is related to obstruction of the trajectory of light); ($l$) balance-point shadow, which is that shadow produced by the reduction in available reflective area, typically of things like corners or edges where surface planes meet.
    • As a rule, the fill light of a shadow shares the hue of the skylight or an adjacent reflected surface light.
    • As a rule, directional shadow of an object is delimited from its light side by a blurred line of darkest shadow known as the terminator.
      • The terminator is darkest because, provided the object’s adjacent surface is reflecting light, directional shadows tend to have fill light.
      • It is also the case that directional shadows tend to have reflected light from adjacent surfaces as fill light to the degree those surfaces received light.
    • Cast shadows tend to have fill light
    • Fill light can be understood to be a result of either ambient light (such as #skylight) or reflected adjacent surface light

• Coloring

  • Coloring is the application of pigments that convey a given hue due to the frequencies of the light they reflect, the frequencies of light they let pass through and the frequencies of light they absorb. Because color is related to light, color is actually enmeshed with rendering. ==It is possible to render without color as parity of or for all wavelengths of light can be assumed for simplification, but it is not possible to color without rendering as the absence or presence of light occurs in relation to the hues of or in the scene==.
    • The less bright the light in a given scene, i.e. the darker the overall scene, the more likely there is to be visible variation in hue even as there is less total visibility. This is because the brighter the light, the more likely the hues will mix together to approximate white–especially in pockets of radiance (refer to 20250221103040-Lighting_Levels). The less bright, the less mixing into white radiance.
    • The less bright the light in a given scene, i.e. the darker the overall scene, the lower the contrast between dark and lit-up areas and the less total visibility. While a given light brightens, the shadow’s level of darkness technically remains the same (as it is only the absence of light, regardless of how bright the light). Remaining the same in this case causes a larger difference, nonetheless, between it and the lit areas of the scene given those lit areas are more brightly lit (refer to 20250221103040-Lighting_Levels).
      • Even if the darkness of shadow technically does not change with heightened brightness, a scene with higher overall brightness reduces the amount and surface area coverage of shadow in the scene (refer to 20250221103040-Lighting_Levels).
    • Lowered brightness causes lower contrast but higher hue variation, while higher brightness causes higher contrast but lower hue variation.
    • The hue / color of a shadow or shade is complementary to the hue / color of the blocked light which cast it or the local surrounding light, due to fill light or radiance–that said, the hue of ambient light predominates both hues and the degree of light independently gives the hue its tonal value (refer to 20251003160739-Relative_Hue_and_Shadows).
  • The main hues to worry about ==that affect the most pigment combinations as well as the most practical initial surface pigment in a painting are the hues that come from ambient light, radiance and artificial lighting==.
    • Ambient light either ($m$) has a predominant hue despite possessing a hue gradient determined by features of the environment (a large, usually distant light source and a kind of global light filter, both of which have aspects that can change over time through things like weather and climate), or ($n$) contains all the hues (i.e., is white).
      • For an open environment, ambient light nonetheless tends to potentially express the whole spectrum of a set of hues along a #gradient, but with one hue predominating for a spectator depending on the #angle and #distance of the source of light relative to the #ground surface and the atmospheric #gases that light has to traverse. For example, because of the gas composition of Earth’s atmosphere and the sun, there is a skew towards blue ambient light for objects on Earth. ==The hue and brightness (or lack thereof) of ambient light can viscerally convey the passage of time==.
        • Weather phenomena like aerosols (in the form of fog, clouds, vapor, haze, smog, etc.), can affect skylight and thereby, in such an open environment, ambient light.
      • For a closed environment (nonetheless containing gas and reflective objects), ambient light’s predominant hue is that of the largest, brightest artificial source of light whose light is being reflected in the space. That is, in a closed environment, ambient light and artificial light can overlap. Nonetheless, it is important to keep white balance in mind.
      • In a porous environment, that is semi-closed but has select openings, there is radiance that comes from that environment and onto its exterior whose hue is determined by interior artificial light. There is also ambient light in its interior that is a mixture of the predominant hue, or the gradients, of what would otherwise be exterior and interior ambient lights. Nonetheless, it is important to keep white balance in mind.
        • An example of a porous environment is a room in a building: things like windows, doors, etc., together with placement of artificial light like a lamp and its bulb type or a candle can affect the brightness and mixture of hues inside that room.
        • The cardinal direction of an opening in the environment, given a geography, may determine how much and how often light passes through.
    • The hue of artificial light is determined by how it is being produced and intentionally filtered.
      • Tungsten light bulbs color temperature skew towards yellow-orange hues. Nonetheless, it is important to keep white balance in mind.
      • Fluorescent light bulbs skew towards green hues. Nonetheless, it is important to keep white balance in mind.
      • Light-emitting diode (LED) light bulbs skew toward whatever hue they’ve been set to emanate, though, typically, they are used to emanate pure white instead.
      • Fire (e.g., campfire or a candle) skews toward red-orange hues, though the color of fire correlates with the heat it is producing. Orange and red are the least hot, yellow or white are hot enough, blue or violet are very hot, and ultraviolet (not visible) is the most hot. This gradient is visible in a flame, though with colors like orange and red predominating. Fire is hottest nearest the combustion point, and coolest furthest the combustion point.
      • A lampshade or any given translucent cover or #obstruction of a light source can act to diffuse (soften, blur, increase light to dark gradient for) a light across a #volume.
      • Keep in mind that most if not all such artificial lighting flickers, though the visibility of this flicker in time depends on whether the frequency is higher than we can expect to capture by the frequency of visual snapshotting.
    • As diffuse light tends to provide lower contrast for what it illuminates, ceteris paribus diffuse light leads to lower starkness in the difference between hues on what it illuminates.
    • Not all diffuse light is ambient light, but all ambient light is diffuse light.
  • The ==hues on the surface of a solid or form are determined by the corresponding object’s: ($o$) available light hues (available environmental electromagnetic frequencies), ($p$) type of reflective behavior, which constrain… (1) reflected/bounced light hues (i.e., re-emitted electromagnetic frequencies), (2) escaped light hues (i.e., electromagnetc frequencies that managed to pass directly through), and (3) removed light hues== (i.e., absorbed electromagnetic frequencies that are thereby “trapped¨ away from the rest of the environment).

• Material exploration and technique

  • Pens and pencils–or, more generally, single-point styli–can be used for rendering and depicting texture through three techniques: hatching, cross-hatching and stippling.
    • Hatching is the creation of parallel lines with varying proximity, higher proximity conveying both darker tonal value and more detailed texture. These parallel lines can convey texture more by having variable curvature.
    • Cross-hatching is the creation of lines that are different #degrees of perpendicular to each other, varying in #direction and #rotation, such that they create #intersections. This can enhance texture and add to a sense of volume by giving expressiveness to more of the dimensions of the surface of the page.
    • Stippling is the grouping of #dots or #points of varying area to varying levels of density so as to create a “dappled” effect. This can be used in place of both previous techniques, as it can be quite versatile for texture and tonal value, and allows higher control over these by reducing opportunities for mistakes or increasing opportunities for adaptation and incorporation of what otherwise would have been mistakes. This is especially beneficial in achieving a comic-based aesthetic.
  • Paintbrushes–or, more generally multi-point / multi-line styli–can be used with paint to express hues, as they can take care of a broader surface area at once and allow for differential layering that can aid, with constraints, in adapting and incorporating mistakes in color.
    • Watercolor is painting based primarily on water retention of a pigment. A wash is tinted water made via a mixture with high water-to-paint ratio. It is recommended when using washes that the paintbrush, while having many points, nonetheless tend to gather together to a crisp point when at rest (i.e., when not being used), and that the paint be on a palette that is disposable.
      • The process of creating a wash involves (1) pulling a small amount of paint from the edge of a paint glob rather than from the middle (as the paint is most concentrated at the middle), (2) mixing water and paint together to the point of forming a small puddle on the palette, and (3) diluting the paint on the brush itself by dipping it repeatedly in water until the desired or preferred tonal value for that hue is achieved (the more diluted the pigment and the more water it has, the lighter the hue).

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