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<blockquote data-quote="WayneF" data-source="post: 673267" data-attributes="member: 12496"><p>I think that was your question. Your D7200 takes 24 megapixel images (6000x4000 pixels). 24-bit RGB image data size is always <strong>3 bytes per pixel</strong>, so 24 megapixel RGB images (standard 24-bits) are all always 24 mp x 3 = 72 million bytes (68.7 MB). That is just how life is. JPG color images are Always 24-bit RGB. 24 megapixels of 3 byte RGB data. And the top line of the PS Image Size box shows this number. Says Pixel Dimensions (they are on next lines), then it shows MB (from pixel dimensions) on this top line. It is width x height x 3 / 1048576 to convert million bytes to MB (1048576 is 1024 x 1024).</p><p></p><p>However, then file data compression can reduce the file size smaller, tremendously smaller if JPG. There are still 24 megapixels (unless you resample smaller).</p><p></p><p>Your D7200 manual on the File Size page (page 380 of the User Manual) says for Large files (6000x4000), then:</p><p></p><p>JPG Fine Compression averages 12.7 MB files</p><p>JPG Normal Compression averages 6.5 MB files</p><p></p><p>Note that Normal compression is NOT "normal". Fine is normal, we like better quality images. Fine is the default provided.</p><p></p><p>The TIFF file will still be the same 24 megapixels, so will Not offer a larger print. It could be better quality, depending (cannot be better than the original JPG image it starts from, but TIFF could prevent adding additional JPG losses in subsequent copies).</p><p></p><p>The size difference is due to file compression methods. TIFF files can be compressed, and LZW compression is commonly provided. LZW is conceptually better, but it compresses much less drastically, because LZW is "lossless" compression. It does not affect image quality, always is best quality. Not many printing places will accept other than JPG however. However <strong>High Quality JPG</strong> is very acceptable for printing.</p><p></p><p>But it has to always be High Quality. Once it is lower quality, it will never improve and never get better again (the lossy data becomes the image data). So out of the camera should be High Quality , and out of the photo editor should be High Quality, and the fewest possible times saved as JPG is the idea. If it will be edited and Saved many times, then save it as TIFF until the last final JPG for printing. Just one of the many advantages of Raw images is that they are not JPG images, not until the one last final save (one time) as High Quality JPG for distribution.</p><p></p><p>JPG compression is "lossy" compression, taking liberties to achieve much smaller files, but with the cost of loss of image quality. These losses involve substituting other colors (possibly similar but different) for some pixels, to make the data easier to compress tremendously. Color is the detail in the images. With strong JPG compression (low quality JPG) you may see 8x8 pixel blocks of all the same color in blank areas, and you likely see fringing around sharp edges. Those are losses, and that is the lower image quality. Technically, JPG is always JPG, even highest levels always have some loss, but High Quality JPG can be very acceptably good. Maximum JPG quality normally does not offer visible benefit, so usually a bit less than Maximum is used, but just don't skimp much on Quality any where, any time.</p><p></p><p>JPG compression is a variable, and JPG Quality is specified when the file is written. Image editors offer a JPG Quality setting, like from High to Low quality. </p><p>A High quality JPG image is a larger file (but still much smaller than the 68 MB uncompressed data).</p><p>A Low quality JPG image is a smaller file. Who wants that?</p><p> </p><p> High Quality files might be 1/4 to perhaps even 1/8 the uncompressed (68 MB) size.</p><p></p><p>The camera offers Normal JPG Quality, and says it is 6.5 MB / 68.7 MB, which is 10% data size (on average).</p><p>But the default is Fine JPG Quality and says it is 12.7 MB / 68.7 MB, which is 18% data size (on average), around 1/5 data size.</p><p>Everyone likes better quality images. The camera Default is is Fine JPG Quality images.</p><p></p><p>In your photo editor, don't specify lower JPG quality. Fairly high JPG quality is the idea, and the goal.</p><p>The purpose of an image is to be a high quality image, and NOT to be a small size file. We can't see it when it is in the file.</p><p>Whenever we can see it (RGB monitor) it is 3 bytes per pixel again (uncompressed).</p><p></p><p>The JPG size numbers are approximate, Not absolutes, because size also varies with image content. An image will lots of blank space (walls, skies, etc - large areas with less detail) will compress better, into a smaller file. </p><p>An image full of small detail (a picture full of tree leaves for example) will not compress as small, and will be larger than other images. If you have several dozen various and different JPG images from the camera in a folder (all the same megapixels), and if you sort that folder by file size, you see that the file size could vary over perhaps a 2 to 1 range. The smallest files will have blank areas (devoid of detail), and the largest file will be a very busy image full of detail.</p><p></p><p>But file size depends on both megapixels and JPG Quality. 6000x4000 pixels will print 20 x 13.3 inches at 300 dpi. If your plan however is to print 6x4 inches, then 1800x1200 pixels does that (300 pixels per inch), and more cannot help. Always keep your pristine original camera file (who knows what the future will want from it?), but you can resample the file copy to be sent for printing.</p></blockquote><p></p>
[QUOTE="WayneF, post: 673267, member: 12496"] I think that was your question. Your D7200 takes 24 megapixel images (6000x4000 pixels). 24-bit RGB image data size is always [B]3 bytes per pixel[/B], so 24 megapixel RGB images (standard 24-bits) are all always 24 mp x 3 = 72 million bytes (68.7 MB). That is just how life is. JPG color images are Always 24-bit RGB. 24 megapixels of 3 byte RGB data. And the top line of the PS Image Size box shows this number. Says Pixel Dimensions (they are on next lines), then it shows MB (from pixel dimensions) on this top line. It is width x height x 3 / 1048576 to convert million bytes to MB (1048576 is 1024 x 1024). However, then file data compression can reduce the file size smaller, tremendously smaller if JPG. There are still 24 megapixels (unless you resample smaller). Your D7200 manual on the File Size page (page 380 of the User Manual) says for Large files (6000x4000), then: JPG Fine Compression averages 12.7 MB files JPG Normal Compression averages 6.5 MB files Note that Normal compression is NOT "normal". Fine is normal, we like better quality images. Fine is the default provided. The TIFF file will still be the same 24 megapixels, so will Not offer a larger print. It could be better quality, depending (cannot be better than the original JPG image it starts from, but TIFF could prevent adding additional JPG losses in subsequent copies). The size difference is due to file compression methods. TIFF files can be compressed, and LZW compression is commonly provided. LZW is conceptually better, but it compresses much less drastically, because LZW is "lossless" compression. It does not affect image quality, always is best quality. Not many printing places will accept other than JPG however. However [B]High Quality JPG[/B] is very acceptable for printing. But it has to always be High Quality. Once it is lower quality, it will never improve and never get better again (the lossy data becomes the image data). So out of the camera should be High Quality , and out of the photo editor should be High Quality, and the fewest possible times saved as JPG is the idea. If it will be edited and Saved many times, then save it as TIFF until the last final JPG for printing. Just one of the many advantages of Raw images is that they are not JPG images, not until the one last final save (one time) as High Quality JPG for distribution. JPG compression is "lossy" compression, taking liberties to achieve much smaller files, but with the cost of loss of image quality. These losses involve substituting other colors (possibly similar but different) for some pixels, to make the data easier to compress tremendously. Color is the detail in the images. With strong JPG compression (low quality JPG) you may see 8x8 pixel blocks of all the same color in blank areas, and you likely see fringing around sharp edges. Those are losses, and that is the lower image quality. Technically, JPG is always JPG, even highest levels always have some loss, but High Quality JPG can be very acceptably good. Maximum JPG quality normally does not offer visible benefit, so usually a bit less than Maximum is used, but just don't skimp much on Quality any where, any time. JPG compression is a variable, and JPG Quality is specified when the file is written. Image editors offer a JPG Quality setting, like from High to Low quality. A High quality JPG image is a larger file (but still much smaller than the 68 MB uncompressed data). A Low quality JPG image is a smaller file. Who wants that? High Quality files might be 1/4 to perhaps even 1/8 the uncompressed (68 MB) size. The camera offers Normal JPG Quality, and says it is 6.5 MB / 68.7 MB, which is 10% data size (on average). But the default is Fine JPG Quality and says it is 12.7 MB / 68.7 MB, which is 18% data size (on average), around 1/5 data size. Everyone likes better quality images. The camera Default is is Fine JPG Quality images. In your photo editor, don't specify lower JPG quality. Fairly high JPG quality is the idea, and the goal. The purpose of an image is to be a high quality image, and NOT to be a small size file. We can't see it when it is in the file. Whenever we can see it (RGB monitor) it is 3 bytes per pixel again (uncompressed). The JPG size numbers are approximate, Not absolutes, because size also varies with image content. An image will lots of blank space (walls, skies, etc - large areas with less detail) will compress better, into a smaller file. An image full of small detail (a picture full of tree leaves for example) will not compress as small, and will be larger than other images. If you have several dozen various and different JPG images from the camera in a folder (all the same megapixels), and if you sort that folder by file size, you see that the file size could vary over perhaps a 2 to 1 range. The smallest files will have blank areas (devoid of detail), and the largest file will be a very busy image full of detail. But file size depends on both megapixels and JPG Quality. 6000x4000 pixels will print 20 x 13.3 inches at 300 dpi. If your plan however is to print 6x4 inches, then 1800x1200 pixels does that (300 pixels per inch), and more cannot help. Always keep your pristine original camera file (who knows what the future will want from it?), but you can resample the file copy to be sent for printing. [/QUOTE]
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