Compressed RAW: For many years I have been shooting in RAW to take advantage of the full data when post processing. My new Fuji X100F has a setting for "compressed RAW," which yields...

RickH Loc: Toronto, Canada

For many years I have been shooting in RAW to take advantage of the full data when post processing. My new Fuji X100F has a setting for "compressed RAW," which yields shots about half the size as uncompressed (approx 21 MB as opposed to 42). A quick search of web info and user reviews suggests that this is essentially lossless. Can this be true? Anyone have experience with compressed RAW?

rmalarz Loc: Tempe, Arizona

Essentially lossless is not lossless.
--Bob

RickH wrote:

For many years I have been shooting in RAW to take advantage of the full data when post processing. My new Fuji X100F has a setting for "compressed RAW," which yields shots about half the size as uncompressed (approx 21 MB as opposed to 42). A quick search of web info and user reviews suggests that this is essentially lossless. Can this be true? Anyone have experience with compressed RAW?

RickH Loc: Toronto, Canada

rmalarz wrote:

Essentially lossless is not lossless.
--Bob

that's my sense, but still would like to hear from those with experience

rmalarz Loc: Tempe, Arizona

I just did a google search on

difference between compressed and uncompressed raw files

quite a lot of articles showing examples of the difference, as well as explaining the difference, as well.
--Bob

RickH wrote:

that's my sense, but still would like to hear from those with experience

pecohen Loc: Central Maine

RickH wrote:

For many years I have been shooting in RAW to take advantage of the full data when post processing. My new Fuji X100F has a setting for "compressed RAW," which yields shots about half the size as uncompressed (approx 21 MB as opposed to 42). A quick search of web info and user reviews suggests that this is essentially lossless. Can this be true? Anyone have experience with compressed RAW?

There are lossless compression methods and they can provide very high compression in particular instances. However, getting 50% compression on typical images does not sound likely with lossless compression.

abc1234 Loc: Elk Grove Village, Illinois

Since there are different ways to compress a file, you do not know if it is really lossless. You could call Fuji and ask them. Or, more practically, find out yourself. Shoot with and without. My standard test setup is a bookshelf, camera on tripod, and either remote release or self-timer. What really matters is how you display your shots. I offer that if you are viewing either on any computer screen or small prints, you will not notice a difference. If you make large prints such as 16x20 and up, you might see a difference close up. A/K/A pixel peeping. However, at "normal" viewing distance, you will probably not see a difference.

Let us know what you find.

RickH Loc: Toronto, Canada

pecohen wrote:

There are lossless compression methods and they can provide very high compression in particular instances. However, getting 50% compression on typical images does not sound likely with lossless compression.

thanks, good advice!

DirtFarmer Loc: Escaped from the NYC area, back to MA

If you have Photoshop:
Using a tripod, take one with, one without.
Load both files into Photoshop as layers
Auto Align the two files (just in case something moved)
Set blending to subtract.
There will be some noise visible just from statistical noise but it should be small.