Pixels And Art Glossary

[Ai]

* Are those supposed to all be synonyms? In that case, I guess Hue Shifting is being covered separately, perhaps in the Hue entry?

* I assume you are aware that there are other color spaces that can be usefully used for calculating gradients (HSL, LAB, LCH), as well as linear RGB versus sRGB, and just left them out to keep things simple?

* The term 'lightness' is associated with HSL channel L, which may be confusing in this context. I believe you used the term 'brightness' (which has no association with any particular colorspace AFAIK) in an earlier entry.

[0xDB]

* Are those supposed to all be synonyms? In that case, I guess Hue Shifting is being covered separately, perhaps in the Hue entry?

There will also be an extra entry for Ramps where I will give examples how the same color can be re-used in different Gradients and possibly arrange the Ramps on a 2D grid with intersections. To be honest, I don't see much of a conceptual/technical difference between saying "the color shifts" or "the hue shifts". Hue shifts for creating cheap effects are overused imo and in most cases don't make any sense at all (but well... maybe there should be an extra entry for them... without my personal judgement about it). Ramp,Gradient,Shift... conceptually all the same.

* I assume you are aware that there are other color spaces that can be usefully used for calculating gradients (HSL, LAB, LCH), as well as linear RGB versus sRGB, and just left them out to keep things simple?

Hence the wording "Primary" and "can be" as opposed to something like "Eligible properties for change are...". I pay attention to phrasing my stuff carefully and packing as much information as possible into each and every word. You can make up any number of derived/calculated secondary properties from the plain RGB model and use those to create gradients. Can also just make gradients by feeling and picking arbitrary colors instead of calculating the changes and having them follow any continuous mathematical function.

Always a struggle finding a balance between simplicity and complexity, especially since most artists are not very likely to also have an affinity to math and technology.

* The term 'lightness' is associated with HSL channel L, which may be confusing in this context. I believe you used the term 'brightness' (which has no association with any particular colorspace AFAIK) in an earlier entry.

It is used here in the sense of 'value as lightness' as described in the entry for Brightness/Lightness/Value. It appears to be the same sense as the L in HSL. Mixing pure color with white increases the Lightness (creates Tints), mixing with black decreases Lightness (creates Shades).

[edit: Actually the L in HSL is NOT "Lightness As Value" but rather some arbitrary Brightness which varies greatly with different hues in that model.]

[Ai]

* Are those supposed to all be synonyms? In that case, I guess Hue Shifting is being covered separately, perhaps in the Hue entry?

There will also be an extra entry for Ramps where I will give examples how the same color can be re-used in different Gradients and possibly arrange the Ramps on a 2D grid with intersections. To be honest, I don't see much of a conceptual/technical difference between saying "the color shifts" or "the hue shifts". Hue shifts for creating cheap effects are overused imo and in most cases don't make any sense at all

Eh, making the shadow a complementary color to the highlight adds contrast and shadow/light separation (it can add contrast while preserving lightness, which is a valuable tool)
This is a classical technique used a lot in historic paintings, not only pixel art.
Certain combos appear more natural than others (yellow light+blue shadow is pretty much natural sunlight, as long as you don't overdo it), but IMO unnaturalness occurs mostly when you make different arbitrary hue adjustments on different ramps, rather than having a general trend of shadows become X-er, lights become Y-er across most ramps. I guess that idea of unifying would fit naturally into an entry on Ramps.

My impression is that here you are covering the concept of interpolating a discrete function, and provide hue as one demo. This does not, IMO, imply the 'hue contrast for additional readability/pop' theory that is behind hue shifting.

Hence the wording "Primary" and "can be" as opposed to something like "Eligible properties for change are...". I pay attention to phrasing my stuff carefully and packing as much information as possible into each and every word.

Okay, my mistake. I agree that R` G` B` and H S V are commonly recognized metrics, regardless of any other opinion I may have of them.

Can also just make gradients by feeling and picking arbitrary colors instead of calculating the changes and having them follow any continuous mathematical function.

Well, yes. For shorter ramps (say <=5), that's quite sensible. For longer ramps, calculating a ramp (which is easy and involves no math, with a decent palette editor) and then adjusting it by hand may produce more consistent results with much less effort.

* The term 'lightness' is associated with HSL channel L, which may be confusing in this context. I believe you used the term 'brightness' (which has no association with any particular colorspace AFAIK) in an earlier entry.

It is used here in the sense of 'value as lightness' as described in the entry for Brightness/Lightness/Value. It appears to be the same sense as the L in HSL. Mixing pure color with white increases the Lightness (creates Tints), mixing with black descreases Lightness (creates Shades).
[/quote]
This is probably just me being pedantic then.... HSL L (or HSV V) is kind of like Lightness. except that Lightness goes up and down as H and S values change, with same L value. So, only if you don't look at it too hard? I think they are intended to do the same thing but in practice do significantly different things.

[0xDB]

Eh, making the shadow a complementary color to the highlight adds contrast and shadow/light separation (it can add contrast while preserving lightness, which is a valuable tool)
This is a classical technique used a lot in historic paintings, not only pixel art.
Certain combos appear more natural than others (yellow light+blue shadow is pretty much natural sunlight, as long as you don't overdo it), but IMO unnaturalness occurs mostly when you make different arbitrary hue adjustments on different ramps, rather than having a general trend of shadows become X-er, lights become Y-er across most ramps. I guess that idea of unifying would fit naturally into an entry on Ramps.

My impression is that here you are covering the concept of interpolating a discrete function, and provide hue as one demo. This does not, IMO, imply the 'hue contrast for additional readability/pop' theory that is behind hue shifting.

There definitely needs to be an entry for Hue Shifting then for the cases where it's not a cheap unnatural effect. The one you describe is also shown in the video I linked to under the Color entry. Emphasizing shadow with a complementary color is in fact an extension of that natural perceptual illusion that the shadow appears to be colored to our eyes in reality when it is in fact still a shade of gray. That's not what I mean by cheap effect. It only feels cheap when the shift is arbitrary(I even did that myself more than once). I was not aware that Hue Shifting specifically refers only to the non-arbitrary appearance derived from the naturally occurring optical illusion. I see a lot of non-sensical hue shifts in Pixel Art which looks kind of funky/fresh/psychadelic but also starts to feel really cheap and overused. So, you're saying Color Shift is arbitrary? Hue Shift refers to one specific optical illusion observable in reality?

This is probably just me being pedantic then.... HSL L (or HSV V) is kind of like Lightness. except that Lightness goes up and down as H and S values change, with same L value. So, only if you don't look at it too hard? I think they are intended to do the same thing but in practice do significantly different things.

Nothing wrong with being pedantic, I just do not see how there could be any confusion there. Lightness is not immediately available as a primary property in HSV/HSB. Value there means something else, see Brightness/Lightness/Value. HSL is something completely different from HSV/HSB and Brightness in HSB isn't even "brightness" in the common sense. There the B is equal to V and it's more related to the common sense of "saturation" which in turn though is different from the sense that S, Saturation has in HSV/B. I believe people will always find this confusing no matter what because there is no consistency in these terms across different color models and no consistency with their common sense interpretation either. Lightness in the sense I use it there seems fully synchronized with what it means to describe.

[AlexHW]

In standard Art terminology, there are the achromatic, and monochromatic gradients. Might be useful to reference those for the sake of comparison.

[Ai]

The one you describe is also shown in the video I linked to under the Color entry. Emphasizing shadow with a complementary color is in fact an extension of that natural perceptual illusion that the shadow appears to be colored to our eyes in reality when it is in fact still a shade of gray.

... I thought the reason that shadows looked blue in sunlight is because they are picking up more atmospheric color (usually blue) than light color. I admit I'm a little skeptical of shadows actually being a shade of grey (though I would agree they can appear grey in low light conditions because of how our eyes work), as I understand light as being multiplicative. Haven't found anything about grey shadows so far, only a lot about colored shadows but I'll watch the video on Color, see if it's explained there.

BTW, I found this while I was looking.

I see a lot of non-sensical hue shifts in Pixel Art which looks kind of funky/fresh/psychadelic but also starts to feel really cheap and overused.

Sure, I agree. I feel this occurs when the artist is thoughtless or lets the artwork become a technique showcase rather than an artwork.

So, you're saying Color Shift is arbitrary? Hue Shift refers to one specific optical illusion observable in reality?

No, sorry. I've never heard the term "color shift" before, inside or outside pixelation TBH. I'm just saying that hue shifts don't have to look weird, and they do occur naturally (and come to think of it, are also a nice approximation of materials with subsurface scattering like skin)

AlexHW's point also seems good, if there is space to compare monochromatic, hue shifted, and excessively hue shifted ramps in an entry, that may communicate the idea well.

I believe people will always find this confusing no matter what because there is no consistency in these terms across different color models and no consistency with their common sense interpretation either.

Excellent point. I guess as long as you avoid explicitly calling the HSL L by its actual long name 'lightness', confusion will be minimized.

[0xDB]

In Photography, Color Shift is synonymous to Color Cast, where it refers to an (usually unwanted) effect that all colors shift towards one specific different color/hue (caused by lack of or improper white balance). From a descriptive point of view however, I don't feel a huge difference between saying "color shifts from a to b" or "hue shifts from a to b" except maybe that saying "hue" is more narrow referring to that one specific property of a color, while "color" encompasses a wide variety of properties that might get shifted.

I know of monochromatic gradients but what are achromatic gradients? Grayscale? (Achromatic color appears to mean color "without color"... so gray?). Gradients/Ramps containing a shift in Hue would be called what, inter-chromatic or polychromatic, or is there a specific term (apart from Hue Shift)?

[0xDB]

I clearly need to update my knowledge about colored shadows.

[AlexHW]

My understanding is that Dichromatic gradient is one that translates from one color to another, since Di means two. Then there's Trichromatic(three different colors on a colorwheel). Polychromatic means multiple colors, and generally refers to images that use multiple colors. I suppose you could have a polychromatic gradient, but this would involve basically two dichromatic gradient stuck together? I learnt about monochromatic gradients and achromatic gradients in general art before I learnt about pixel-art, so I'm more attached to that way of classifying things and might be a way to bridge things with general art.
They are classed under the types of Value Scales.
Also, one thing I'm unsure about is whether there is a better term for gradients that begin with a strong color and transition to an achromatic color. Because achromatic gradients tend to refer to gradients that lack any color/hue, even though you could probably put colors that are near grey into it and still call it achromatic (because there are achromatic colors).

[Ai]

It looks like possibly Alex meant a different thing by 'monochromatic' gradient than my interpretation. Typically I think of a monochromatic gradient as what you get if you lay down a panel of color, then use Blend tool in Multiply mode to progressively darken it with a greyscale gradient -- ie. a gradient in which all colors have the same hue and saturation.

(This doesn't always happen because blend modes and especially color spaces are imperfect, but that's the general idea)

Personally I'd be inclined to say that color -> grey or grey -> color gradients have rather marginal usefulness in pixel art. (painting and cinematics are a different story)