# Bio Rust

> Free digital art technique library: anime and character construction, digital painting fundamentals, process and provenance for artists, and free brushes, textures and palettes.

Every page is an ordered method written and tested by the Bio Rust studio (https://biorust.com/about/editors/), and every article lists its sources. Free to read and to quote with a link. No ads, no accounts, no cookies; visits are counted only as cookieless aggregate page views. Section header still lifes are illustrative and generated, as disclosed on the methodology page.

## Start here
- [How to Draw Anime Eyes](https://biorust.com/tutorials/anime-eyes/): the best known method in the archive
- [Values Before Color](https://biorust.com/tutorials/values-before-color/): the fix for most muddy paintings
- [How to Document Your Art Process](https://biorust.com/tutorials/document-your-art-process/): proving a piece is yours

## Character & Anime Art (https://biorust.com/character-anime-art/)
Faces, figures, and stylized character work. The flagship of Bio Rust since the beginning, rebuilt with the techniques that earned the archive its name.
- [How to Draw Anime Eyes: A Complete Method](https://biorust.com/tutorials/anime-eyes/): The eye is the anchor of a stylized face. Build it in the same order every time, from the gap to the lash line to the iris, and it stops feeling like luck.
  Sections: Start with the gap, not the eye; Build the upper lash line as the heaviest shape; Place the iris so the eye has a direction; Make the iris glow with two values and one highlight; Coloring the iris with layer modes; The shadow under the lash line is what makes it read; Anime eye styles across eras and demographics; Common mistakes and how to fix them; Final checklist for how to draw anime eyes
  Sources: https://docs.krita.org/en/tutorials/inking.html; https://www.nationalgallery.org.uk/paintings/glossary/chiaroscuro; https://docs.krita.org/en/reference_manual/blending_modes.html
- [Anime Face Proportions: Head Construction From Any Angle](https://biorust.com/tutorials/face-proportions-anime/): A reliable construction for the stylized head that survives being turned: ball, jaw, wrapping cross, then features, with the measurements in eye heights and head widths for front, three quarter and profile.
  Sections: The ball and jaw; The wrapping cross; Anime face proportions by view, in eye heights and head widths; Turning the head: three quarter view and profile; Age and gender shifts in anime head proportions; Common failures and fixes; Anime face proportions in one pass
  Sources: https://www.tate.org.uk/art/art-terms/f/foreshortening; https://www.nationalgallery.org.uk/paintings/glossary/perspective; https://www.nationalgallery.org.uk/paintings/glossary/underdrawing
- [How to Draw Anime Hair as Blocks, Not Strands](https://biorust.com/tutorials/hair-flow-blocks/): Stop drawing individual hairs. Group hair into a few large flowing masses from the crown, ink the edges with weight, and add one band of shine, and the whole thing reads as hair.
  Sections: Find the crown first; Block three to five masses; How many masses each hairstyle needs; Inking hair with line weight; One band of shine; Common mistakes and how to fix them; How to draw anime hair, in one pass
  Sources: https://docs.krita.org/en/tutorials/krita-brush-tips/hair.html; https://www.nationalgallery.org.uk/paintings/glossary/chiaroscuro; https://docs.krita.org/en/tutorials/inking.html

## Digital Painting (https://biorust.com/digital-painting/)
Light, color, and rendering. How to move from flat shapes to painted form using values, edges, and considered brushwork.
- [Layer Blend Modes for Shading, Explained](https://biorust.com/tutorials/layer-modes-shading/): Multiply, Screen, Overlay and Add do most of the work in digital shading. Here is what each one is for, the stack that uses them, and the order to build it.
  Sections: Multiply is for shadow; Screen and Add are for light; Overlay is for pushing color and contrast; A worked layer stack for shading; The order to build shadow, light, bounce and color; Where the modes live, and what they are called; Troubleshooting: when a mode misbehaves; Layer blend modes for shading, in short
  Sources: https://www.w3.org/TR/compositing-1/; https://docs.krita.org/en/reference_manual/blending_modes.html; https://help.procreate.com/procreate/handbook/layers/layers-blend; https://helpx.adobe.com/photoshop/desktop/repair-retouch/adjust-light-tone/blending-mode-descriptions.html
- [Blend Modes Cheat Sheet for Digital Painting](https://biorust.com/reference/layer-modes/): The blend modes that do the real work in digital painting, what each does to the pixels beneath it, the job it is best suited for, and a starting opacity. Keep it open while you paint.
  Sections: The blend modes cheat sheet: every mode that matters; Darken family: when to reach for Multiply; Lighten family: Screen for light, Add for the accent; Contrast family: Overlay and Soft Light to unify; Color family: recolor without touching value; Blend mode names across Procreate, Clip Studio, Krita and Photoshop; Common blend mode mistakes; Using the blend modes cheat sheet
  Sources: https://www.w3.org/TR/compositing-1/; https://docs.krita.org/en/reference_manual/blending_modes.html; https://helpx.adobe.com/photoshop/desktop/repair-retouch/adjust-light-tone/blending-mode-descriptions.html; https://help.procreate.com/procreate/handbook/layers/layers-blend
- [Values in Painting: Why Your Color Looks Off](https://biorust.com/tutorials/values-before-color/): If a painting looks wrong in color, it is almost always wrong in value. Build the value structure in three greys before you touch hue, and color becomes the smaller half of the job.
  Sections: What value actually is, and why the eye reads it first; Common color complaints and the value cause behind each; The three-value blocking exercise; How to run the squint test; Checking values digitally: three ways to see greyscale; Adding color on top of a solid value structure; Mistakes that break values in painting, and the fix for each; Values first, then color
  Sources: https://www.nationalgallery.org.uk/paintings/glossary/grisaille; https://www.tate.org.uk/art/art-terms/t/tone; https://www.nationalgallery.org.uk/paintings/glossary/chiaroscuro; https://docs.krita.org/en/reference_manual/filters/adjust.html
- [Hard and Soft Edges: Controlling the Eye](https://biorust.com/tutorials/edge-control/): Edges are a language. Where you put hard, soft and lost edges tells the viewer where to look, what a surface is made of, and how fast a form turns away from the light.
  Sections: The edge vocabulary: hard, firm, soft and lost; Edges and the focal point; Edges describe material; Edges describe the speed of the turn; A ten minute sphere exercise, timed; Edge mistakes and the fix for each; Hard and soft edges, in short
  Sources: https://www.nationalgallery.org.uk/paintings/glossary/sfumato; https://www.tate.org.uk/art/art-terms/p/painterly; https://docs.krita.org/en/reference_manual/brushes/brush_engines/color_smudge_engine.html

## Process and Provenance (https://biorust.com/process-provenance/)
How to document your process, prove a piece is yours, read image provenance, and tell generated imagery from real process work. Practical craft for artists working in the age of generated art.
- [How to Document Your Art Process](https://biorust.com/tutorials/document-your-art-process/): A repeatable way to keep thumbnails, construction, session saves, layered files and timelapse so you can show exactly how a piece was made, and prove authorship when someone asks.
  Sections: Why an art process record beats any single proof; What to keep at each stage of the work; Session saves and naming so timestamps tell a story; Turn on timelapse recording and leave it on; Name your layers like a working artist; What a good record can and cannot prove; How to share proof without giving your work away; Mistakes that weaken a process record; Document your art process in three habits
  Sources: https://help.procreate.com/procreate/handbook/actions/actions-video; https://www.nationalgallery.org.uk/paintings/glossary/pentimento; https://c2pa.org/specifications/specifications/2.1/index.html
- [Content Credentials and C2PA for Artists](https://biorust.com/tutorials/content-credentials-c2pa-artists/): A Content Credential is a signed record of who made a file and what was done to it. Here is what the manifest holds, how to read one, and where it stops being proof.
  Sections: What are Content Credentials; What a C2PA manifest records; How the standard labels generated imagery; How to read a credential with the public Verify tool; What happens to Content Credentials on upload; What Content Credentials cannot prove; How an artist can use Content Credentials well; Mistakes artists make with Content Credentials; Content Credentials as one layer of evidence
  Sources: https://c2pa.org/specifications/specifications/2.1/index.html; https://cv.iptc.org/newscodes/digitalsourcetype/; https://contentcredentials.org/verify; https://contentauthenticity.org/faq
- [How to Tell If Art Is AI: A Craft-Based Method](https://biorust.com/tutorials/spot-ai-generated-art/): A craft-based way to judge whether an image was generated: provenance and process first, then construction, edges, light and detail, with an honest account of how reliable each tell is.
  Sections: Check provenance before you squint; How to tell if art is AI: the tells by craft area; Why tells decay as generators improve; Ask for process, politely; What detection tools can and cannot tell you; Mistakes that lead to false accusations; A fair review checklist; How to tell if art is AI, in short
  Sources: https://arxiv.org/abs/2402.03214; https://nvlpubs.nist.gov/nistpubs/ai/NIST.AI.100-4.pdf; https://contentcredentials.org/verify
- [AI Art vs Human Art: What Hand Technique Teaches](https://biorust.com/tutorials/ai-art-vs-hand-made-technique/): What image generators do well, what they cannot give you, and why construction, value and edge control matter more when a machine can output a finished-looking picture in seconds.
  Sections: AI art vs human art: what each actually gives you; What construction, value and edge skill let you do that prompting cannot; Why learn to draw when a machine can render; Authorship, copyright and the records that prove it; Misconceptions on both sides of the argument; A practice plan for the age of generated art; AI art vs human art, in short
  Sources: https://www.copyright.gov/ai/; https://www.copyright.gov/ai/Copyright-and-Artificial-Intelligence-Part-2-Copyrightability-Report.pdf; https://syntheticmedia.partnershiponai.org/
- [Image Metadata for Artists](https://biorust.com/tutorials/image-metadata-for-artists/): Every image carries hidden fields beside its pixels. Fill the ones that claim your work, strip the ones that leak your location, and test what each platform keeps.
  Sections: EXIF, IPTC and XMP: the three families of image metadata; The IPTC fields an artist should fill, with example values; Removing location data before you post; How to test what a platform strips; What image metadata can and cannot prove; Mistakes artists make with image metadata; Image metadata as the readable layer of your record
  Sources: https://iptc.org/standards/photo-metadata/iptc-standard/; https://exiftool.org/TagNames/XMP.html; https://cv.iptc.org/newscodes/digitalsourcetype/; https://exiftool.org/
- [How to Check Where an Image Came From](https://biorust.com/tutorials/check-image-provenance/): Before you credit, repost or accuse, trace the image. Seven checks in a fixed order, from the largest copy to the visual tells, with a log of what each one showed.
  Sections: The five questions behind an image provenance check; Seven checks, in order; What each check can show, and what it cannot; Getting more from reverse image search; Documenting what you found; When the trail goes cold; Mistakes that break an image provenance check; Image provenance in one routine
  Sources: https://contentcredentials.org/verify; https://c2pa.org/specifications/specifications/2.1/index.html; https://iptc.org/standards/photo-metadata/iptc-standard/; https://firstdraftnews.org/articles/verifying-online-information-the-absolute-essentials/
- [Why AI Image Detectors Flag Real Art](https://biorust.com/tutorials/ai-image-detector-false-positives/): Why automated detectors misread stylized and heavily polished hand-made work, what the research actually found, and how artists, judges and moderators should treat a score.
  Sections: What an AI image detector is actually measuring; Why stylized hand-made work gets flagged; What the 2024 study of eight detectors found; How a score should be treated by artists, judges and moderators; If a detector flags your work; Build the record before you need it; The honest limits of any AI image detector
  Sources: https://arxiv.org/abs/2402.03214; https://nvlpubs.nist.gov/nistpubs/ai/NIST.AI.100-4.pdf; https://contentcredentials.org/verify
- [Accused of Using AI Art? How to Respond](https://biorust.com/tutorials/respond-to-ai-art-accusations/): A calm, evidence first playbook for artists accused of posting generated work: what to share, what to keep private, how to appeal, and how to stop it happening again.
  Sections: First, step away from the comments for an hour; A calm, evidence first response in five steps; What to share publicly, and what to keep private; Three kinds of accuser and the right response to each; How to appeal a platform or contest removal; Artists have always left a trail; Know where your rights stand; Make the next accusation easier to answer; Accused of using AI art: the method in short
  Sources: https://www.nationalgallery.org.uk/paintings/glossary/pentimento; https://www.nationalgallery.org.uk/paintings/glossary/underdrawing; https://www.copyright.gov/ai/
- [Artist Statement: Write It in Your Own Voice](https://biorust.com/tutorials/artist-statement-ai-writing/): Your artist statement, bio and captions are part of the record around your art. Write them from process notes, keep them specific, and say plainly when a writing tool helped.
  Sections: What an artist statement is, and what it is not; Statement, bio, caption and grant paragraph compared; Drafting an artist statement from your process notes; Artist statement examples: generic against specific; What to cut so the statement sounds like you; How to disclose help from a writing tool; What text detectors get wrong, and what to do about it; Keep your drafts the way you keep your sketches; Your artist statement, in short
  Sources: https://hai.stanford.edu/news/ai-detectors-biased-against-non-native-english-writers; https://arxiv.org/abs/2304.02819; https://artificialintelligenceact.eu/article/50/; https://www.nyfa.org/knowledge-base/the-art-of-the-application/the-artist-statement-5-dos-and-donts/

## Free Resources (https://biorust.com/free-resources/)
Free for personal and commercial use, no attribution required.
- [Free Brushes: Getting Started With the Sets](https://biorust.com/tutorials/free-brushes-guide/): Which of the free Bio Rust sets suits which job, how to import them into Procreate, Clip Studio and Krita, how to tune pressure, and how to keep a small brush library you actually use.
- [Ink & Lineart Brush Set](https://biorust.com/free-resources/ink-lineart-brushes/): Twelve crisp tapering brushes for character line work. Natural pressure taper, minimal texture, and one inker you can use for a whole piece.
- [Painterly Brush Set](https://biorust.com/free-resources/painterly-brushes/): Sixteen textured round brushes for blocking, blending, and rendering in digital painting. Most finished pieces need only three of them.
- [Paper & Canvas Texture Pack](https://biorust.com/free-resources/paper-canvas-textures/): Ten tileable grain overlays to give digital work a made by hand surface. Set to Overlay or Soft Light at low opacity, applied last.
- [Muted Color Palette Collection](https://biorust.com/free-resources/muted-palettes/): Twenty considered palettes in low saturation ranges for skin, fabric, and atmosphere. Eight swatches each, ordered from light to dark.

## Optional
- [Tutorials archive](https://biorust.com/tutorials/)
- [About and manifesto](https://biorust.com/about/)
- [Studio and editors](https://biorust.com/about/editors/)
- [Methodology](https://biorust.com/methodology/)
- [Contact](https://biorust.com/contact/)
- [Privacy](https://biorust.com/privacy/)
- [Terms](https://biorust.com/terms/)