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<p>[QUOTE="Burton Strauss III, post: 2163058, member: 59677"]Even a smartphone or tablet camera will give better results than a scanned photo copy.</p><p><br /></p><p>Here's why...</p><p><br /></p><p>The photocopier is optimized for a flat sheet of paper on glass. That's the precise focus point for the 1000s of little camera & lenses used to scan the document.</p><p><br /></p><p>Strike 1 - coins are not flat</p><p><br /></p><p>The highest resolution copiers that I know of are 2400x2400 dots per inch (dpi). That creates a massive 513MP (mega pixel) image. Even a 600x600dpi scan is 32MP. So the file is MASSIVELY compressed. Compression takes adjacent pixels that are 'almost' the same color and merges them into large shapes that can be stored more compactly (from here to here it's all this single color). So the fine details are lost to compression</p><p><br /></p><p>Strike 2</p><p><br /></p><p>The printing side of the color copier then puts ink to paper. The inks are never 100% perfect matches to the colors of the image</p><p><br /></p><p>Strike 3</p><p><br /></p><p>Now you scan that paper with another scanner. If the resolution of the second scanner is lower than the printing resolution - more averaging. If the resolution is higher, you create false detail. Even if they are precisely the same, no matter how hard you try, the dots never line up perfectly. So each dot of the second generation scan is going to be the average of 2 side by side or 4 adjacent dots.</p><p><br /></p><p>Strike 4</p><p><br /></p><p>Then that 2nd generation scanned image is compressed.</p><p><br /></p><p>Strike 5</p><p><br /></p><p>Then of course it's displayed on a 72dpi monitor, but we can zoom it to get past that.</p><p><br /></p><p>Ball 1</p><p><br /></p><p><br /></p><p>In any league I've ever played, 1 and 5 is a losing count.</p><p><br /></p><p><br /></p><p>You can prove this to yourself in about 90 seconds. Take a page of typescript and copy it. Copy the copy. Compare the two - gen 0 with gen 2 - you will see how the letters aren't quite aligned, the little jagged 'straight' lines are visible if you use a magnifying glass and the way the letters spread out a tiny bit.</p><p><br /></p><p><br /></p><p>So take a look here: [ATTACH]416707[/ATTACH] it's just my tablet sitting on a block of wood with the under counter fluorescent lights providing illumination.</p><p><br /></p><p>But that 8MP camera produced this image:</p><p><br /></p><p>[ATTACH=full]416711[/ATTACH]</p><p><br /></p><p>Not a great one, mind you, but not a terrible one - that's this weekend's TNA show admission medal. DCAM Aluminum. Notice how the lettering is a bit washed out.[/QUOTE]</p><p><br /></p>
[QUOTE="Burton Strauss III, post: 2163058, member: 59677"]Even a smartphone or tablet camera will give better results than a scanned photo copy. Here's why... The photocopier is optimized for a flat sheet of paper on glass. That's the precise focus point for the 1000s of little camera & lenses used to scan the document. Strike 1 - coins are not flat The highest resolution copiers that I know of are 2400x2400 dots per inch (dpi). That creates a massive 513MP (mega pixel) image. Even a 600x600dpi scan is 32MP. So the file is MASSIVELY compressed. Compression takes adjacent pixels that are 'almost' the same color and merges them into large shapes that can be stored more compactly (from here to here it's all this single color). So the fine details are lost to compression Strike 2 The printing side of the color copier then puts ink to paper. The inks are never 100% perfect matches to the colors of the image Strike 3 Now you scan that paper with another scanner. If the resolution of the second scanner is lower than the printing resolution - more averaging. If the resolution is higher, you create false detail. Even if they are precisely the same, no matter how hard you try, the dots never line up perfectly. So each dot of the second generation scan is going to be the average of 2 side by side or 4 adjacent dots. Strike 4 Then that 2nd generation scanned image is compressed. Strike 5 Then of course it's displayed on a 72dpi monitor, but we can zoom it to get past that. Ball 1 In any league I've ever played, 1 and 5 is a losing count. You can prove this to yourself in about 90 seconds. Take a page of typescript and copy it. Copy the copy. Compare the two - gen 0 with gen 2 - you will see how the letters aren't quite aligned, the little jagged 'straight' lines are visible if you use a magnifying glass and the way the letters spread out a tiny bit. So take a look here: [ATTACH]416707[/ATTACH] it's just my tablet sitting on a block of wood with the under counter fluorescent lights providing illumination. But that 8MP camera produced this image: [ATTACH=full]416711[/ATTACH] Not a great one, mind you, but not a terrible one - that's this weekend's TNA show admission medal. DCAM Aluminum. Notice how the lettering is a bit washed out.[/QUOTE]
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