# ARNOLD — Knowledge MOC > [!abstract] About this MOC > Everything **Arnold**-specific — lookdev nodes, lighting practice, render optimization, integration (HTOA, etc.), and utility workflows (cryptomatte, material transfer). Start with *Fundamentals* if you are new to Arnold, then jump to the *By Task* section when you need a recipe. --- ## 🧭 Reading Order for Newcomers 1. **Shading theory** → [[../LOOKDEV/Notes/SHADING Theory And Practice|SHADING — Theory & Practice]] — reads Arnold `standard_surface` in depth. 2. **Lighting theory** → [[../LIGHTING/Notes/LIGHTING Theory|LIGHTING Theory]] — light transport fundamentals. 3. **Lighting in Arnold** → [[../LIGHTING/Notes/LIGHTING Arnold Practice|LIGHTING — Arnold Practice]] — lights, samples, AOVs. 4. **Render faster** → [[Notes/Arnold Optimization Noise|Arnold — Optimization & Noise]] — sampling strategy, noise reduction. 5. **Extract mattes** → [[Notes/Arnold Cryptomatte|Arnold Cryptomatte]]. --- ## 📚 Fundamentals Start here if Arnold is new to you. - [[../LOOKDEV/Notes/SHADING Theory And Practice|SHADING — Theory & Practice]] — PBR and every lobe of Arnold `standard_surface`. - [[../LIGHTING/Notes/LIGHTING Theory|LIGHTING Theory]] — physical light, exposure, energy conservation. - [[../LIGHTING/Notes/LIGHTING Arnold Practice|LIGHTING — Arnold Practice]] — the hands-on version, in Arnold. --- ## 🎨 Lookdev Nodes and shaders for material authoring. - **Nodes** - [[Notes/RaySwitch|RaySwitch]] — route different shading logic based on ray type (camera, shadow, reflection, diffuse…). - **Shaders** - [[Notes/Arnold hair|Arnold Hair]] — fur / hair shading with the dedicated Arnold shader. - **Workflow** - [[Notes/Arnold Transfert Material|Arnold — Transfer Material]] — move a material cleanly from one asset to another. --- ## 💡 Lighting - [[../LIGHTING/Notes/LIGHTING Arnold Practice|LIGHTING — Arnold Practice]] — lights, samples, AOV strategy. - [[Notes/Arnold Cryptomatte|Arnold Cryptomatte]] — ID mattes for comp. --- ## 📷 Camera & Effects - [[../../OUT OF PUBLISH/BHGC Arnold bokeh|Arnold — Bokeh (BHGC)]] — depth of field / bokeh setup. - [[Notes/Arnold Fog Environment volumetrique|Arnold — Fog / Volumetric Environment]] — atmosphere, fog, god rays. --- ## ⚙️ Optimization Keep renders clean and cheap. - **General** - [[Notes/Arnold Optimization Noise|Arnold — Optimization & Noise]] — samples, clamps, denoise strategy. - [[../../OUT OF PUBLISH/BHGC Arnold optimization|Arnold — Optimization (BHGC)]] — external render-opt notes. - **By Node** - [[Notes/RaySwitch|RaySwitch]] — avoid expensive shading on indirect rays. --- ## 🛠️ Integration Getting Arnold to talk to other DCCs. - [[Notes/Arnold Houdini HTOA|Arnold Houdini — HTOA]] — installation + basic use of Arnold inside Houdini. --- ## 🔗 Related MOCs - [[../LOOKDEV/LOOKDEV KNOWLEDGE MOC|LOOKDEV Knowledge MOC]] — generic PBR theory, cross-renderer. - [[../LIGHTING/LIGHTING MOC|LIGHTING MOC]] — lighting theory and practice. - [[../MARI/MARI MOC|MARI MOC]] — texturing upstream of Arnold. - [[../KNOWLEDGE MOC|KNOWLEDGE MOC]] — top-level index.