Lightroom Convert to DNG

[John Friar]

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

 

[Erik Baumgartner]

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

 

[John Friar]

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

 

[Erik Baumgartner]

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

 

[Kaoticphoto]

Dng it's just a container.

When people (me, at least) talk about preprocessing raf files to dng, it's about use a raf processor , like iridient x-transformer or dxo pure raw2, that execute the demosaicing (and if requested other corrections like nr,sharpening, etc) to original raf, exporting a dng.

Just converting a raf to dng with LR and reimporting it in LR again doesn't change nothing to final IQ

 

[John Friar]

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

 

[Erik Baumgartner]

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

 

[John Friar]

Dng it's just a container.

When people (me, at least) talk about preprocessing raf files to dng, it's about use a raf processor , like iridient x-transformer or dxo pure raw2, that execute the demosaicing (and if requested other corrections like nr,sharpening, etc) to original raf, exporting a dng.

Just converting a raf to dng with LR and reimporting it in LR again doesn't change nothing to final IQ

I like the benefits of .dng over .raf. If the xtrans data is preserved then I can also benefit from future improvements in the de-mosaicing process.

 

[Erik Baumgartner]

Dng it's just a container.

When people (me, at least) talk about preprocessing raf files to dng, it's about use a raf processor , like iridient x-transformer or dxo pure raw2, that execute the demosaicing (and if requested other corrections like nr,sharpening, etc) to original raf, exporting a dng.

Just converting a raf to dng with LR and reimporting it in LR again doesn't change nothing to final IQ

I like the benefits of .dng over .raf. If the xtrans data is preserved then I can also benefit from future improvements in the de-mosaicing process.

What benefits?

 

[Kaoticphoto]

I think you will always have raf to dng converter in the future.

So I don't see the reason to use dng now, if you don't need a better demosaicing .

Even because dng usually take 3x more disk space than a compressed raf.

 

[John Friar]

Dng it's just a container.

When people (me, at least) talk about preprocessing raf files to dng, it's about use a raf processor , like iridient x-transformer or dxo pure raw2, that execute the demosaicing (and if requested other corrections like nr,sharpening, etc) to original raf, exporting a dng.

Just converting a raf to dng with LR and reimporting it in LR again doesn't change nothing to final IQ

I like the benefits of .dng over .raf. If the xtrans data is preserved then I can also benefit from future improvements in the de-mosaicing process.

What benefits?

No sidecar file has several benefits.

My original question is about what is going on when Lightroom is used to import a .raf file and converts to .dng. Bottom line…is the xtrans raw data preserved. The relative benefits can be evaluated once I know that. You may not see the benefits and that is fine. That’s not what the I’m seeking to know.

 

[John Friar]

1. Erik Baumgartner wrote:

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

There are several options, with differing degrees of quality.

 

[Erik Baumgartner]

1. Erik Baumgartner wrote:

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

There are several options, with differing degrees of quality.

And you can apply them to an Adobe DNG file?

 

[John Friar]

1. Erik Baumgartner wrote:

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

There are several options, with differing degrees of quality.

And you can apply them to an Adobe DNG file?

Yes, that’s correct.

 

[John Friar]

1. Erik Baumgartner wrote:

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

There are several options, with differing degrees of quality.

And you can apply them to an Adobe DNG file?

Yes, that’s correct.

Assuming the dng contains Un-demosaiced data.

 

[Erik Baumgartner]

1. Erik Baumgartner wrote:

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

There are several options, with differing degrees of quality.

And you can apply them to an Adobe DNG file?

Yes, that’s correct.

Assuming the dng contains Un-demosaiced data.

Well, I’m asking, have you actually been able to do it or not?

 

[John Friar]

1. Erik Baumgartner wrote:

After reading about some of the benefits of converting RAW files to DNG, I went ahead and converted my existing Fuji XTrans files as well as now converting files on import.

So far, so good. I then did some digging around and stumbled upon this...

https://www.dpreview.com/forums/thread/4478827

That thread is 2 years old, so I thought it best to start a new one! In short, and if I understand it correctly, converting .raf files to .dng will perform a demosaicing process resulting in a file that cannot take advantage of future improvements in XTrans processing. This didn't sound right.

I then downloaded RawTherapee so that I could take a peak at the .dng files after conversion/import. What I found, when viewing without any demosaicing applied, is that the original XTrans matrix is preserved. In other words, the conversion/import only repackages the raw data and does not apply the demosaicing algorithm.

Does this sound right to you? Am I missing something? If correct, the case for converting to .dng is now stronger (for me).

Thanks,

John

The DNG can be setup to include the original RAF within it (huge file), but otherwise the Adobe DNG converter will always irreversibly demosaic (partially) the original RAW using its less than stellar processing and leave you with a resulting file that is typically larger than the original unmolested lossless compressed RAF (as well as stripping out some proprietary metadata). I fail to see what possible advantage there could be to doing this. Please enlighten me.

I'm just relaying what I found...that the raw data is preserved (according to RawTherapee). And no, I didn't include the original raf file.

How do you know the RAW data is preserved? Can you still apply Raw Therapee’s demosaicing?

I opened the file in RawTherapee and selected the drop down demosaic option to none. The displayed raster is clearly an XTrans matrix.

Can you select other than none? If none is even an option, it’s already been demosaiced.

There are several options, with differing degrees of quality.

And you can apply them to an Adobe DNG file?

Yes, that’s correct.

Assuming the dng contains Un-demosaiced data.

Well, I’m asking, have you actually been able to do it or not?

Here's a screen capture showing the demosaic options (none is selected).

So yes, I have actually done it.

 

[John Friar]

1. Kaoticphoto wrote:

I think you will always have raf to dng converter in the future.

So I don't see the reason to use dng now, if you don't need a better demosaicing .

Even because dng usually take 3x more disk space than a compressed raf.

That’s a good point. With files from my XPro2, I’m seeing the size go from approximately 20mb (raf) to 30mb (dng).

 

[FujiShooterCY]

Why on the Earth one would do this?

What you have, are digital originals. Preserve them untouched. This is the first thing which the discipline of archiving and preserving digital assets teach us.

If you pack the original RAF into DNG without demosaicing, you gain nothing but you loose disk space and time.

If you pack the original RAF into DNG after demosaicing you loose everything. You loose IQ because Adobe demosaicing of RAF is inferior. You loose authenticity because you are trashing your original authentic digital assets (RAFs). You loose disk space and time, too.

The optimal strategy here is to store your authentic RAFs "as is", maybe adding their SHA256 checksums somewhere at the same location. If you are concerned about availability of applicable demosaicing software after some 20-30-50 years, just store the source code snapshot of appropriate software right aside your RAFs (think darktable or RawTherapy, both are open source). This way your posterity will be able to recover the images from RAFs just via porting the preserved software to whatever computer platform will be available of that time. Or maybe they will find some more recent editions of applicable software, which aren't yet developed as of today.

 

[John Friar]

Why on the Earth one would do this?

What you have, are digital originals. Preserve them untouched. This is the first thing which the discipline of archiving and preserving digital assets teach us.

If you pack the original RAF into DNG without demosaicing, you gain nothing but you loose disk space and time.

If you pack the original RAF into DNG after demosaicing you loose everything. You loose IQ because Adobe demosaicing of RAF is inferior. You loose authenticity because you are trashing your original authentic digital assets (RAFs). You loose disk space and time, too.

The optimal strategy here is to store your authentic RAFs "as is", maybe adding their SHA256 checksums somewhere at the same location. If you are concerned about availability of applicable demosaicing software after some 20-30-50 years, just store the source code snapshot of appropriate software right aside your RAFs (think darktable or RawTherapy, both are open source). This way your posterity will be able to recover the images from RAFs just via porting the preserved software to whatever computer platform will be available of that time. Or maybe they will find some more recent editions of applicable software, which aren't yet developed as of today.

There are several reasons why one would do this, as well as good reasons not to (loss of some metadata and increase in file size). So certainly not loose-loose.

I was not proposing de-mosaicing and then packing into a dng file. The bottom line is, I was seeking confirmation on my findings...that is, the original Xtrans matrix data is preserved when using Lightroom to convert to dng upon import or subsequently using the menu option. To me, based on what I can see and understand, it is true that the Xtrans matrix data is preserved and, therefore, provides a degree of future proofing.