Luminous Landscape Forum

Equipment & Techniques => Digital Cameras & Shooting Techniques => Topic started by: adrian tyler on September 23, 2008, 08:39:27 am

Title: compress D3 raw files or not
Post by: adrian tyler on September 23, 2008, 08:39:27 am
the D3 offers a "compressed" form of saving RAW files, which is about half of the size of the non compressed files, are there any disadvantages in using this method? is it lossless?

thanks

adrian
http://www.adriantyler.net/ (http://www.adriantyler.net/)
Title: compress D3 raw files or not
Post by: NikosR on September 23, 2008, 09:03:24 am
Quote
the D3 offers a "compressed" form of saving RAW files, which is about half of the size of the non compressed files, are there any disadvantages in using this method? is it lossless?

thanks

adrian
http://www.adriantyler.net/ (http://www.adriantyler.net/)
[a href=\"index.php?act=findpost&pid=223568\"][{POST_SNAPBACK}][/a]

You have the option of 'lossless compressed' and 'compressed'. If you want lossless guess which one you need to choose.
Title: compress D3 raw files or not
Post by: adrian tyler on September 23, 2008, 09:07:18 am
Quote
You have the option of 'lossless compressed' and 'compressed'. If you want lossless guess which one you need to choose.
[a href=\"index.php?act=findpost&pid=223576\"][{POST_SNAPBACK}][/a]


so "lossless" realy means "lossless" and not "almost lossless" and is identical to "uncompressed", right?
Title: compress D3 raw files or not
Post by: DarkPenguin on September 23, 2008, 09:20:01 am
yes
Title: compress D3 raw files or not
Post by: NikosR on September 23, 2008, 09:26:44 am
Quote
so "lossless" realy means "lossless" and not "almost lossless" and is identical to "uncompressed", right?
[a href=\"index.php?act=findpost&pid=223579\"][{POST_SNAPBACK}][/a]

Lossless compressed is not identical to uncompressed, it is compressed  

You have 3 options: Uncompressed, compressed and lossless compressed. How difficult can it be to make sense of these?
Title: compress D3 raw files or not
Post by: adrian tyler on September 23, 2008, 09:40:46 am
Quote
Lossless compressed is not identical to uncompressed, it is compressed  

You have 3 options: Uncompressed, compressed and lossless compressed. How difficult can it be to make sense of these?
[a href=\"index.php?act=findpost&pid=223591\"][{POST_SNAPBACK}][/a]


i thought it common knowledge that all forms of data compression are to a more or lesser extent destructive.

my "difficulty" is not understanding but believing...

thanks anyway.
Title: compress D3 raw files or not
Post by: NikosR on September 23, 2008, 10:12:52 am
Quote
i thought it common knowledge that all forms of data compression are to a more or lesser extent destructive.


[a href=\"index.php?act=findpost&pid=223596\"][{POST_SNAPBACK}][/a]

This is far from the truth. In fact nothing would have been working properly around us in this digital age if that were true.  Compressing 00000000 to 8X0 is not to any extent a destructive operation.
Title: compress D3 raw files or not
Post by: DarkPenguin on September 23, 2008, 10:37:08 am
Quote
i thought it common knowledge that all forms of data compression are to a more or lesser extent destructive.

my "difficulty" is not understanding but believing...

thanks anyway.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=223596\")

That's a myth.

You have a set of bits.  If you end up with an identical set of bits after compressing/decompressing then it is lossless.

[a href=\"http://en.wikipedia.org/wiki/Lossless_compression]http://en.wikipedia.org/wiki/Lossless_compression[/url]

http://en.wikipedia.org/wiki/Common_knowledge (http://en.wikipedia.org/wiki/Common_knowledge)
Title: compress D3 raw files or not
Post by: Panopeeper on September 23, 2008, 11:22:44 am
I don't know why Nikon included the "uncompressed" option at all, if not for those, who would be scared away from the camera for they associate "compressed" with "lossy" due to the D70, D100, D200. It has been a dumb decision that time to offer only lossy compression (or, with the D70, not to offer any selection).
Title: compress D3 raw files or not
Post by: adrian tyler on September 23, 2008, 12:05:26 pm
great news, thanks
Title: compress D3 raw files or not
Post by: Panopeeper on September 23, 2008, 01:25:13 pm
Quote
My personal preference is not to compress.

That's exactly what I was thinking of, when posting above

Quote
I don't know why Nikon included the "uncompressed" option at all, if not for those, who would be scared away from the camera for they associate "compressed" with "lossy"

If you believe, that not compressing is a guarantee against errors in the raw file, you need to look around. Both Canon and Nikon had already released firmware versions without proper testing, and created useless raw files.
Title: compress D3 raw files or not
Post by: NikosR on September 23, 2008, 02:18:52 pm
Quote
I don't know why Nikon included the "uncompressed" option at all, if not for those, who would be scared away from the camera for they associate "compressed" with "lossy" due to the D70, D100, D200. It has been a dumb decision that time to offer only lossy compression (or, with the D70, not to offer any selection).
[a href=\"index.php?act=findpost&pid=223627\"][{POST_SNAPBACK}][/a]

Uncompressed offers some advantage in the speed of opening the file for postprocessing. Insignificant in the case of one file, noticeable in the case of a batch of lots of files. That's about the only advantage I have been able to identify personally