DNG conversion

[lightroomtoolbox]

Lightroom Version Number

15.5

Operating System

1. Windows 11

I have a question about DNG format. I do own a Sony A7RiV which does not have lossless compressed raw files. Raw files without compression are about 130Mb each. This makes lightroom work slowly and forces the need of lot of storage. DNG files from those raw have half of the size and lightroom works notably faster. My question is about future compatibility. Are Adobe DNG files compatible with other software? Is it a risk to convert every new photo to DNG and delete original raws (ARW format)?

 

[clee01l]

DNG is a non-proprietary file format, The data in the primary data block can be RAW or RGB, Lossy compressed or lossless compressed. Most software supports it as a RAW file Type and as RGB data. Several camera Manufacturers (Pentax, Leica, Apple and others) offer it as the native file storage out of the camera.

 

[lightroomtoolbox]

DNG is a non-proprietary file format, The data in the primary data block can be RAW or RGB, Lossy compressed or lossless compressed. Most software supports it as a RAW file Type and as RGB data. Several camera Manufacturers (Pentax, Leica, Apple and others) offer it as the native file storage out of the camera.

Is DNG a complete standard? I have read somewhere but could not find it again that there is an open standard, but Adobe uses Adobe DNG which is propietary and not complete compatible with the original DNG

 

[clee01l]

Is DNG a complete standard? I have read somewhere but could not find it again that there is an open standard, but Adobe uses Adobe DNG which is propietary and not complete compatible with the original DNG

DNG is an open standard developed by ADOBE expressly for the purpose of universal use. You probably misread that description. If I'm not mistaken, Apple has modified the DNG standard for iPhones. So, it may not completely adhere to the Adobe Published specs.

 

[Replytoken]

Is it a risk to convert every new photo to DNG and delete original raws (ARW format)?

Would it bother you if Sony came out with better software in the future for processing their photos and you no longer had the raw files to work with?

--Ken

 

[lightroomtoolbox]

Would it bother you if Sony came out with better software in the future for processing their photos and you no longer had the raw files to work with?

--Ken

Not really, I do not use Sony software, but I may use capture one, dark table, etc. If they will understand the dng format, I am ok

 

[clee01l]

Would it bother you if Sony came out with better software in the future for processing their photos and you no longer had the raw files to work with?

--Ken

I don't think deleting the RAW files is ever the answer. Just look at all of the AI advancements by Adobe and others that need the original RAW file as the basis. Once you convert the RAW data to RGB, you fix the WB and while 16 bit RGB is the common today it might be superceded in the future. My first RAW files were DNGs from a Pentax taken 18years ago. Because I had the original SOOC DNG. I have been able to reprocess these using DeNoise , Adaptive Color, etc. and greatly improve a 10MP 2008 image.

 

[clee01l]

Not really, I do not use Sony software, but I may use capture one, dark table, etc. If they will understand the dng format, I am ok

While a 60mp images is about the high end today Sony could improve the RAW image delivery by producing a lossless RAW file SOOC. Nikon has for several years now saved a 43mp 14bit RAW image as a lossless compressed NEF of 55-60MB size. All of the apps you mention can handle the RAW DNGs

Your comment about LrC being slow, processing 60mp images is not going to change with any app because the first thing the apps will do is decompress the lossless file type and expand it to full dimensions and then demosaic it to RGB. So you will end up with the same full dimension RGB image that Classic uses to process. If any thing your workflow will be slower because you will have introduced a step to convert the proprietary File Type to DNG.

I think your solution here is going to be to get a faster RISC computer and abandon the slower CISC computer processing completely.

 

[Johan Elzenga]

Is it a risk to convert every new photo to DNG and delete original raws (ARW format)?

Just store the originals on an external drive, that you only use for this and disconnect if you don’t need it.

 

[Replytoken]

I don't think deleting the RAW files is ever the answer. Just look at all of the AI advancements by Adobe and others that need the original RAW file as the basis. Once you convert the RAW data to RGB, you fix the WB and while 16 bit RGB is the common today it might be superceded in the future. My first RAW files were DNGs from a Pentax taken 18years ago. Because I had the original SOOC DNG. I have been able to reprocess these using DeNoise , Adaptive Color, etc. and greatly improve a 10MP 2008 image.

I agree 100%. But the OP wanted to convert the files, and that was why I posed the question. I have no objections to DNG files if that is what one wants/needs, but I would always want the original raw files as well.

--Ken

 

[Califdan]

I don't know if it has been mentioned in this thread yet, but if you tend to save your metadata (which included edits) to disk, with an ARW that updates a very small XMP file (and perhaps an ACR file as well)l whereas with a DNG that data gets inserted into the actual DNG file requiring the entire file to be re-written. Many backup systems will then be triggeted to copy that entire DNG file to the backup device or to the cloud. For a cloud backup service that can be quite a lot of data if you do much editing.

For example, I once fixed the spelling on a parent keyword (with auto write XMP data turned on) and the result was 3 days of uploading DNG files to my cloud backup service.

 

[lightroomtoolbox]

I don't know if it has been mentioned in this thread yet, but if you tend to save your metadata (which included edits) to disk, with an ARW that updates a very small XMP file (and perhaps an ACR file as well)l whereas with a DNG that data gets inserted into the actual DNG file requiring the entire file to be re-written. Many backup systems will then be triggeted to copy that entire DNG file to the backup device or to the cloud. For a cloud backup service that can be quite a lot of data if you do much editing.

For example, I once fixed the spelling on a parent keyword (with auto write XMP data turned on) and the result was 3 days of uploading DNG files to my cloud backup service.

If I convert to DNG before importing to lightroom, then lightroom does not write xmp but modifies the DNG?

 

[lightroomtoolbox]

While a 60mp images is about the high end today Sony could improve the RAW image delivery by producing a lossless RAW file SOOC. Nikon has for several years now saved a 43mp 14bit RAW image as a lossless compressed NEF of 55-60MB size. All of the apps you mention can handle the RAW DNGs

Your comment about LrC being slow, processing 60mp images is not going to change with any app because the first thing the apps will do is decompress the lossless file type and expand it to full dimensions and then demosaic it to RGB. So you will end up with the same full dimension RGB image that Classic uses to process. If any thing your workflow will be slower because you will have introduced a step to convert the proprietary File Type to DNG.

I think your solution here is going to be to get a faster RISC computer and abandon the slower CISC computer processing completely.

Sony did include lossless compression in Sony A7RiV-a, a minor hardware upgrade. They now has in all models.
I have tried proccesing the same photo in Lightroom and DNG works much faster, I guess disk reading is a bottleneck. I use ssd for my most recent photos, hdd for backups and older photos. I do also would like to need less storage capacity

 

[Hal P Anderson]

If I convert to DNG before importing to lightroom, then lightroom does not write xmp but modifies the DNG?

If you ask Lightroom to save a copy of your metadata to disk, it always writes XMP data into the DNG, no matter when you convert to DNG.