Clean repository and update .gitignore
- Remove build artifacts from git tracking (build/, dist/, __pycache__/, *.spec) - Updated .gitignore to properly exclude generated files - Added old_code/ documentation folder - Updated sample_data.txt to show new 5-field format - Exclude user-specific conf/app.conf from tracking
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old_code/DOTTED_TEXT_SOLUTION.md
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old_code/DOTTED_TEXT_SOLUTION.md
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# Print Quality Issue - Dotted/Pixelated Text Solution
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## 🔍 Problem Identified
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**Issue:** Text appears dotted/pixelated on printed labels (like dot-matrix printer output)
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- PDF looks perfect on screen ✅
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- But printed output has dotted text ❌
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- Not smooth/sharp like expected
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---
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## 🎯 Root Cause
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The problem is in the **print pipeline**, not the PDF:
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1. **PDF is generated correctly** at 1200 DPI with vector fonts
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2. **Printing process rasterizes** (converts to bitmap) the PDF
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3. **Rasterization happens at LOW resolution** (150-300 DPI typically)
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4. **Result:** Dotted text instead of smooth vectors
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### Why This Happens:
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```
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PDF (Vector) → SumatraPDF → Low DPI Raster → Printer Driver → Dotted Output
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↑ Problem here! Converts to low-res bitmap
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```
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The printer receives a **bitmap image** at low resolution, not the original vector graphics.
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---
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## ✅ Solutions Implemented
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### **Solution 1: Printer Quality Configuration (CRITICAL)**
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Updated `print_label.py` to configure printer for HIGH QUALITY before printing:
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```python
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# New function: configure_printer_quality()
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- Sets PrintQuality = 600 DPI (not draft mode)
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- Sets TTOption = DMTT_BITMAP (sharper text)
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- Configures paper size to 35mm x 25mm
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```
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**This is now automatic** - runs before every print job.
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---
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### **Solution 2: GhostScript Printing (BEST QUALITY)**
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Added GhostScript as primary printing method:
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**Why GhostScript is Better:**
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- ✅ Maintains **vector graphics** (not rasterized)
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- ✅ Renders directly to printer at **1200 DPI**
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- ✅ Perfect text anti-aliasing
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- ✅ No intermediate bitmap conversion
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**Printing Priority:**
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1. **GhostScript** (if installed) - BEST quality
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2. SumatraPDF (fallback) - Good quality
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3. ShellExecute (fallback) - Uses default PDF viewer
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4. Open file (last resort) - Manual printing
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---
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## 🚀 How to Get Best Quality
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### **Option A: Install GhostScript (Recommended)**
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1. **Download GhostScript:**
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- Go to: https://ghostscript.com/releases/gsdnld.html
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- Download: "GPL Ghostscript 10.04.0 for Windows (64 bit)"
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2. **Install:**
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- Run installer
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- Use default installation path
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- No special configuration needed
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3. **Test:**
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```powershell
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python print_pdf_ghostscript.py
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```
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Should show: ✅ GhostScript found
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4. **Print:**
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- Just run your GUI normally
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- It will automatically use GhostScript
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- You'll see: "Using GhostScript for high-quality vector printing..."
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**Result:** Perfect, sharp text with no dotting!
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---
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### **Option B: Configure Printer (Without GhostScript)**
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If you can't install GhostScript, the code now **automatically** configures printer quality.
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But you should also manually check:
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1. **Open Printer Preferences:**
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```powershell
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.\configure_label_size.ps1
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```
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2. **Set Quality to HIGHEST:**
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- Look for "Print Quality" or "Resolution"
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- Set to: **600 DPI** or **Best** or **High Quality**
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- NOT "Draft" or "Normal" or "Economy"
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3. **Disable Dithering:**
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- Look for "Dithering" or "Halftone"
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- Set to: **None** or **Off**
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4. **Set Graphics Mode:**
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- Look for "Graphics" or "Text Quality"
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- Set to: **Vector** or **High Quality**
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---
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## 📊 Quality Comparison
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| Method | Text Quality | Speed | Installation |
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|--------|--------------|-------|--------------|
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| **GhostScript** | ⭐⭐⭐⭐⭐ Perfect | Fast | Requires install |
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| **SumatraPDF + Quality Config** | ⭐⭐⭐⭐ Very Good | Fast | No install needed |
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| **SumatraPDF (default)** | ⭐⭐ Dotted | Fastest | No install needed |
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---
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## 🧪 Testing
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### Test 1: Check Current Method
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```powershell
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# Start GUI
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.\venv\Scripts\python.exe label_printer_gui.py
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# Watch console output:
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# Should say one of:
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# "Using GhostScript for high-quality vector printing..." ← BEST
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# "Label sent to printer via SumatraPDF..." ← OK
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```
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### Test 2: Verify GhostScript
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```powershell
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python print_pdf_ghostscript.py
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```
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Expected output:
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```
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✅ GhostScript found at: C:\Program Files\gs\gs10.04.0\bin\gswin64c.exe
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GhostScript is available for high-quality PDF printing
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```
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### Test 3: Print Test Label
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```powershell
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python test_quality.py
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```
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Check printed output:
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- ✅ Text should be **smooth and sharp**
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- ✅ No dotted appearance
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- ✅ Crisp edges on checkmark image
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- ✅ Professional quality
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---
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## 🔧 Troubleshooting
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### Still seeing dotted text?
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#### Check 1: Printer Driver Quality
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```powershell
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# Run configuration script
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.\configure_printer_quality.ps1
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# Manually verify:
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# Settings > Printers > Labels > Printing preferences
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# Quality = HIGHEST (600 DPI or more)
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```
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#### Check 2: Print Method Used
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Look at console output when printing:
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- **GOOD:** "Using GhostScript..."
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- **OK:** "Printer configured: 35x25mm @ HIGH QUALITY"
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- **BAD:** "Could not configure printer quality"
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If you see "Could not configure printer quality":
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- Printer driver doesn't support programmatic quality changes
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- MUST configure manually in printer preferences
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#### Check 3: Label Material
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- **Wrong:** Plain paper (not designed for thermal printing)
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- **Right:** Thermal labels (heat-sensitive or transfer)
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Wrong label material can cause poor quality even with correct settings.
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#### Check 4: Printer Hardware
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```powershell
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# Print self-test from printer
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# (Usually hold button while powering on)
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```
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If self-test also shows dotted text:
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- Printer may be in draft mode
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- Check printer's physical control panel
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- Look for "Quality" or "Darkness" dial/setting
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- May need firmware update
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---
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## 📝 Technical Details
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### Why Dotted Text Happens:
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**Normal printing workflow:**
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```
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PDF → Printer Driver → Sharp output
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```
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**What was happening:**
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```
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PDF (vector, 1200 DPI)
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↓
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SumatraPDF rasterizes at LOW DPI (150-300)
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↓
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Bitmap sent to printer
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↓
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Printer prints bitmap → DOTTED TEXT
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```
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**What we fixed:**
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```
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Method 1 (GhostScript):
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PDF (vector) → GhostScript → Printer @ 1200 DPI → SHARP TEXT
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Method 2 (Quality Config):
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PDF → Configure printer to 600 DPI → SumatraPDF → Better quality
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```
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### Key Settings:
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1. **PrintQuality = 600**: Tells Windows to render at 600 DPI minimum
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2. **TTOption = 2 (DMTT_BITMAP)**: Renders TrueType fonts as graphics (sharper)
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3. **GhostScript -r1200**: Renders PDF at full 1200 DPI resolution
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4. **TextAlphaBits=4**: Anti-aliasing for smooth text edges
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---
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## 🎓 Recommendations
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### For Production Use:
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1. **Install GhostScript** on all computers
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- One-time setup
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- Always best quality
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- No manual configuration needed
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2. **Keep PDF backup enabled**
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- Review PDFs to confirm they look correct
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- PDFs are always high quality
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3. **Test periodically**
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- Print quality can change after:
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- Windows updates
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- Driver updates
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- Printer hardware changes
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---
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## 📞 Quick Reference
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### If text is dotted:
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```powershell
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# 1. Install GhostScript (best solution)
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# Download from: https://ghostscript.com/releases/gsdnld.html
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# 2. Or configure printer manually
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.\configure_label_size.ps1
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# Set quality to HIGHEST
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# 3. Test
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python test_quality.py
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```
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### Check print method:
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```powershell
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# Look for this in console output:
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"Using GhostScript..." # ← You have best quality!
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"Printer configured: 35x25mm @ HIGH QUALITY" # ← Good
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```
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---
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**Last Updated:** February 13, 2026
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**Status:** Multiple solutions implemented - GhostScript recommended for best quality
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