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Is small image file size means low image quality?what is JPEG image file size of 5d mark iv .Can we achive better image in small image file size?

marked as duplicate by flolilo, Philip Kendall, Hueco, xiota, mattdm Sep 16 '18 at 17:30

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  • Please try and split this up into one clearly defined and answerable question - Stack Exchange isn't a format which deals well with posts which ask more than one question. – Philip Kendall Sep 14 '18 at 14:59
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    Image size has nothing to do with quality - much like a 1-second .wav probably won't have lower quality than a 2-hour .mp3. As to the 5D IV's specifications: Have you even read the manual? As to your last quastion: better than what? – flolilo Sep 14 '18 at 14:59
  • An image of a flat single-color surface with even lighting and no details at all will compress a lot smaller than a highly detailed landscape image, with no significant difference in the loss of quality (although the flat image may look a bit worse because there's no details for the JPEG artifacts to get lost among). Final JPEG size is highly dependent on the content of the image as well as the encoding options you use (quality, subsampling, etc) – twalberg Sep 14 '18 at 15:14
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    Harjun, please do a little bit of research before posting your question. What is the relationship between file size and image quality is a good question. What is the JPG file size for the 5Dmk4 is not - as it's easily answerable by you simply cracking the manual. As for can better quality be achieved in a small file - this cannot be answered unless you define what you mean by "better". This usually involves setting parameters like: is the image destined for web or print? If print, what size will it be printed and at what distance will the viewer see the print? – Hueco Sep 14 '18 at 18:06

File sizes of JPEG images can be highly variable depending upon the image contents, even when comparing files with the same resolution and "quality" setting created with the same camera. This is due to the way they use compression to reduce file sizes. An image that is uniform in color and brightness will compress much smaller than an image that contains many different colors and brightnesses, even when both are compressed at the same "image quality" setting.

Canon publishes 'typical' file sizes for the various in-camera JPEG quality settings. For the 5D Mark IV, they list the following on pages 171-172 of the EOS 5D Mark IV Instruction Manual :

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As you can see, there are "quality" settings of 'Fine' and 'Normal' at various resolutions. The difference between the 'Fine' and 'Normal' settings is in the degree of compression used when the JPEG is created.

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