Pros and Cons of DNG file format and how to convert camera raw to DNG?

[badbluesman]

What is the best method for converting large numbers of camera raw files to DNG format?

Is there any danger that my files might become corrupted in the process? Any other possible downsides or pros and cons of doing this conversion?

I am considering converting all of my Sony raw shoots to DNG going forward. I am really getting tired of Sony's quirky raw file format and its poor compatibility with some programs, specifically Photo Mechanic (by Camera Bits), which I use for sorting, deleting and renaming prior to processing.

I am currently shooting with Sony A7r IV cameras exclusively.

[TheDigitalDog]

There are several advantages and a few disadvantages to DNG. 

See:

https://www.cnet.com/news/adobe-offering-new-reasons-to-get-dng-religion/

http://digitaldog.net/files/ThePowerofDNG.pdf

The easiest way to convert a boatload is in Lightroom Classic. Of course, the free DNG converter can do so as well. One can convert to DNG on import to Lightroom Classic, and if you so desire, save off the proprietary raws to another drive (that's up to you). 

I've never seen corruption when converting, and I believe some verification takes place at this time (and as seen above, can be done after in Lightroom Classic). 

The two (IMHO minor downside) to DNG is:

1. Proprietary metadata tags are not understood. So if you ever go back to the Sony converter, those tags are essentially gone (even if, big if, the converter could deal with DNG). 

2. Backups may take longer because the beauty of DNG as a container is it stores all kinds of data above and beyond the raw sensor data. Even a fully rendered JPEG of the edits you could make. So you may be backing up a DNG if you made one tiny instruction-based edit if that metadata is stored in the DNG, which is an option. That wouldn't be the case with sidecar files. Frankly, all my backups take place automatically at night while I'm deep asleep, so for me, no issue. 

[Rob_Cullen · Accepted solution]

There are many opposing opinions about "DNG". Rather than explain here I give you some links to research-

https://blog.adobe.com/en/publish/2015/12/07/dng-pros-cons-and-myths

https://helpx.adobe.com/camera-raw/using/adobe-dng-converter.html

https://helpx.adobe.com/camera-raw/digital-negative.html

Apparently some cameras record proprietary metadata that is not compatible with DNG- Someone else will need to address this topic. (out of my league!) Done by DigitalDog- beat me to post 🙂

[TheDigitalDog · Accepted solution]

Apparently some cameras record proprietary metadata that is not compatible with DNG- Someone else will need to address this topic. (out of my league!) Done by DigitalDog- beat me to post 🙂

By @Rob_Cullen

DNG supports private tags where that proprietary data can be stored. The issue is it's proprietary, and the original converters that could access it are unlikely to support DNG, so it's 'lost'. Could those companies read (for free) and support DNG as they do for JPEGs or TIFFs (two other openly documented formats anyone can use?). Yes, they could. 

[badbluesman]

Thanks. These links were very helpful. I experimented with conversion yesterday and will probably continue it going forward.

Just one follow up question: When converting during LRC import, is there a way to set your own destination folder? The default setting is burried deep in the system library under Pictures. I will probably post this question separatelty as it is really an LRC question.

[TheDigitalDog]

You can create as many import presets to store location, profiles or other presets etc.

https://helpx.adobe.com/in/lightroom-classic/help/photo-video-import-options.html

[ElizabethOOOG]

I've been purging the proprietary profiles, it's part of my first proof process. It's the first thing I do upon first review of a shoot. Usually I can force a header rewrite in RAW or DNG with a minor crop. Hate duplicates. I can't count on software developers profiles and formats. Too many variables. Forward.

[TheDigitalDog]

I've been purging the proprietary profiles, it's part of my first proof process. I

By @ElizabethOOOG

What proprietary profiles?

[ElizabethOOOG]

Every one. I prefer Knolls RAW or Lab to start. It's not for everyone, I can read color numbers and translate the expected output. I studied under Knoll and Dan Margulies, few others not available now

.

[TheDigitalDog]

Every one. I prefer Knolls RAW or Lab to start. It's not for everyone, I can read color numbers and translate the expected output. I studied under Knoll and Dan Margulies, few others not available now

.

By @ElizabethOOOG

Sorry, I have no idea what you're referring to (Knolls RAW)? What proprietary profiles specifically (they have names)?

Perhaps you mean Dan Margulis?

And does this have anything to do with the topic:

Pros and Cons of DNG file format and how to convert camera raw to DNG?

[Zesty_wanderlust15A7]

- www.adobe.com/creativecloud/file-types/image/raw/dng-file.html

- DNG vs RAW – Which One is Better and Why

http://photographylife.com/dng-vs-raw

- Why I No Longer Convert RAW Files to DNG

http://photographylife.com/why-i-no-longer-convert-raw-files-to-dng

[TheDigitalDog]

- Why I No Longer Convert RAW Files to DNG

Mostly FUD. 

DNG conversion doesn't increase workflow time on import. Not on modern hardware (maybe the fellow in 2015 had some slower machine, today, it's not even worth consideration). 

I only care about processing DNG in products that support it (outside of Adobe, I have no less than three products that also support DNG). 

The idea of no point of return is silly unless you are sure you'll use the manufacturer's raw converter (cause, again, anything proprietary in the original is only understood there). 

There is no myth about future compatibility if you examine the 30+ years of digital imaging file formats: openly documented file formats (JPEG, TIFF, DNG) are good; I can open a TIFF I made in Photoshop 1.0.7 today in Photoshop 2023. Proprietary formats (historically those from Live Picture, Xres, Color Studio: dead). 

But use whatever you wish (and ignore all the advantages of DNG outlined in the URLs earlier). 

It isn't for everyone. It isn't perfect. Perfection is the enemy of good. 

[ElizabethOOOG]

Depends what's in the DNG, bit-depth important for big tonal moves. Adobe doesn't support it very well. I think they gave up. Too many versions. I'm looking into Affinity. I hope people keep their digital negative files after seeing some of the corrections. There's a big difference between a photographer and a drum scanner operator. I EA'd Live Picture, PS, and Scene7. I was wondering what happened to the live picture.