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Old Feb 1, 2007, 12:27 PM   #1
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I recently bought a new 5D and have noticed that the frames remaining display is way off. Example imediately after formatting my 2gb SanDisk Ultra II my frames remaining display reads 114. I'm capturing in RAW only and I find that I can shoot 178 images before the card is full. What's up with that?




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Old Feb 1, 2007, 5:03 PM   #2
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It's only an estimate (worst case), since each picture varies in size
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Old Feb 2, 2007, 6:21 AM   #3
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If you shoot a clear blue sky and an ocean wave, you will have a resonably small
image size, pixel wise...Very little color variations in that shot...If you shoot a shot full of color your image size will dramaticly increase...NHL is right, its a guess-ta-mate...
:?
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Old Feb 2, 2007, 7:43 AM   #4
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Sorry guys...

Do you mean the RAW filessize varies evenat a given number of pixels (i.e. for a given camera...) That would mean there is some sort of compression in the format?

I thought RAW meant raw data, each pixel stores the same information, thus the file size is the same for every picture...

If you shoot JPEG, the file varies because of the compression OK...

Can you exlpain? Is RAW something else than RAW?


EDITED a BIG spelling error...
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Old Feb 2, 2007, 9:12 AM   #5
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Raw is the raw image data, but the .cr2 file size does vary.

I always suspected the camera was performing some sort of lossless compression on the images (maybe something like lzw of huffman?) on the files to try to squeeze more onto the storage cards.
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Old Feb 2, 2007, 1:33 PM   #6
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The RAW image format used byCanon dSLRsis CR2, which is a 'lossless' compressed image format developed by Canon. A CR2 file is smaller than a 'RAW' image, but much larger than a JPG image. The exact size of the CR2 file varies due the content of the image itself and how "compressable" it is.
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Old Feb 3, 2007, 11:36 AM   #7
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And that's why Steve is the all knowing Daddy LOL!!
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Old Feb 8, 2007, 8:18 AM   #8
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Thanks for clearing this up guys cuz what got me wondering is that my KM 7D always stores exactly the same number of RAW images each time. Guess there is no compression going on with KM. Not that is necessarily a good thing.
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