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Uncompressed RAW files

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Uncompressed RAW files
« on: 31 / October / 2012, 20:13:45 »
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All entry level DSLRs compress RAW files which results in loss of image quality in order to justify the high price of higher end models that allow for uncompressed RAW files.

I was wondering if there is any project as such that is working on this so that uncompressed RAW files can be attained from entry level DSLRs. I think this will be a great project if people start working on it.

An uncompressed RAW file from an entry level DSLR will close the gap in image quality to higher models of the same mega pixel.

Re: Uncompressed RAW files
« Reply #1 on: 31 / October / 2012, 20:24:08 »
All entry level DSLRs compress RAW files which results in loss of image quality in order to justify the high price of higher end models that allow for uncompressed RAW files.
It always nice to blame something like this on a conspiracy by the manufacturers to cheat the public.   But in reality,  if Canon could get good pure RAW files from those cameras they would as a way to sell against Nikon.  And visa-versa.

It seems to me that what is more likely to be happening is that the manufacturers are providing some preprocessing to their RAW files to correct for lens aberrations prior to the consumer seeing the images.    You only have to look at what CHDK RAW files look like (especially at full wide angle) to see this.  Entry level DSLR's are inexpensive for a reason - a good Nikon 50mm lens costs almost as much as an entry level DSLR - they have to cut corners somewhere.
 
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I was wondering if there is any project as such that is working on this so that uncompressed RAW files can be attained from entry level DSLRs. I think this will be a great project if people start working on it.
Well,  if there is it won't be called CHDK as CHDK only works on Canon P&S cameras.   You might try googling for "Magic Lantern" if you want a DSLR project.

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An uncompressed RAW file from an entry level DSLR will close the gap in image quality to higher models of the same mega pixel.
Not if you don't use a similiar quality lens.  Its the glass that decides in the end - you can't fix that simply by storing RAW images rather that JPG's.
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Uncompressed RAW files
« Reply #2 on: 31 / October / 2012, 20:28:44 »
With SD cards dirt cheap, why compress RAW files?

Its is not a conspiracy but just like AMD and intel disable some cores in a chip in order to fit them in the price range the same way camera makers are compressing RAW files to cripple a camera in order for it not to compete with their more expensive models.

Almost half of the data is thrown away, you can find this out by seeing the compression options that higher-end models provide.

But thanks. I'll try to find a DSLR source.

Re: Uncompressed RAW files
« Reply #3 on: 31 / October / 2012, 20:54:41 »
UPDATE : thank philmoz for the posting below ....

With SD cards dirt cheap, why compress RAW files?
Specmanship ?   People buying entry level DSLR's are typically not experienced photographers.   So if  Brand-C can fit 2000 image on an SD card and Brand-N can only fit 1600 images on that card then clearly Brand-C must be better.

Also,  I think you will find the images from those processed and compressed RAW files are a lot better than pure RAW files if you don't plan to post-process those files.

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Its is not a conspiracy but just like AMD and intel disable some cores in a chip in order to fit them in the price range the same way camera makers are compressing RAW files to cripple a camera in order for it not to compete with their more expensive models.
I disagree.   If Canon could out sell Nikon by providing a better entry level DSLR they would.   Their more expensive models typically have much better lenses and sensors and a whole pile of other features including build quality.  They protect nothing by providing compressed RAW - its a trivial difference compared to the other differences.  Go into a camera store and spend 15 minutes with an entry camera vs a high end one ( and I don't mean Walmart).

And AMD and Intel  play the game with disabling cores in the chip as a way of managing yields.  When a chip comes off the line,  those parts of the wafer that have defects in one core get downgraded to be lesser spec chips.  Simple economics.

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Almost half of the data is thrown away, you can find this out by seeing the compression options that higher-end models provide.
Again,  higher-end models have better sensors and lenses.   So the raw data from those cameras is actually usable as it comes off the sensor.   The cheaper models need a lot of post-processing  to get good results.  And from what I've read on this forum,  very few people actually have the photoshop skills to match the quality of the processing that even the cheapest Canon P&S provides.

But hey -  if you still think real RAW is something you must have from a $500 DSLR then feel free to start and lead the project.   If nothing else,  you will probably have a lot of fun with it !


« Last Edit: 31 / October / 2012, 22:07:02 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16


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Offline philmoz

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Re: Uncompressed RAW files
« Reply #4 on: 31 / October / 2012, 21:06:04 »
All entry level DSLRs compress RAW files which results in loss of image quality in order to justify the high price of higher end models that allow for uncompressed RAW files.

I was wondering if there is any project as such that is working on this so that uncompressed RAW files can be attained from entry level DSLRs. I think this will be a great project if people start working on it.

An uncompressed RAW file from an entry level DSLR will close the gap in image quality to higher models of the same mega pixel.

What are you basing this on?

Canon RAW files are compressed using a lossless compression algorithm - this is true of all Canon DSLRs from entry level right up to the 1DX.

There is no loss of image quality from the raw compression used on any Canon camera.

Phil.
CHDK ports:
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