Does DNG Affect Image Quality? What You Must Know!

Image quality is particularly important to us photographers. Anything that may adversely affect image quality we need to be aware of.

Does DNG affect image quality? What you must know! No. Converting a RAW file to DNG does not affect the image quality. The conversion is lossless, and the conversion creates a new and smaller file which Adobe software works with more quickly. The original RAW data can be embedded in the new DNG file to ensure that metadata is not lost.

So that is a no then.

Blimey – what is this all about? Do we need to concern ourselves with this?

The point of my blog is to explain things to photographers to help us all with our photography, which for me is all about taking photos and not getting lost in things that we really do not need to worry about.

To fully answer the question though I need to do some explaining about DNG and other camera file formats. Don’t worry, I will explain this little lot in plain English and will not get bogged down in irrelevant detail.

I will only tell you what you need to know – if you want to go deeper into this there is lots of in-depth stuff out there on the internet.

But not here.

What is DNG?

DNG is a camera file format created by Adobe. DNG stands for Digital Negative.

What are camera file formats?

These are the file formats that digital cameras use to save an image as a workable file on a memory card. Pdf is another file format. That’s all – we don’t need to worry about this too much.

What are the main camera file formats?

The main camera file formats are

• RAW
• JPEG
• DNG
• TIFF (which is the file format I use when I save a file out of Photoshop).

You can read more RAW and JPEG in my post JPEG file format: The what, the how and the why.

There are other file formats, but I want to focus on DNG here.

Why are there different camera file formats?

Different users have different needs. The very crude split of RAW/ JPEG is this

• RAW – pro photographers
• JPEG – consumer/ hobbyist photographers

I know that this is a huge generalisation but hopefully you get the point. This post is not a RAW vs JPEG post after all.

OK – lets leave JPEG to one side now and get back to the question in hand. Before we can explore DNG we need to understand what a RAW file is.

What is RAW?

You can find out more in the post above, but in brief a RAW file is just that – a file with nothing done to it. No processing is applied at the time of image capture other than creating the RAW file.

I like the food analogy – the RAW file is the RAW ingredients, and the JPEG file is the cooked meal that needs seasoning. You can do anything you want to the RAW ingredients, much less so to the cooked meal.

Does that make any sense?

RAW means RAW

A RAW file has not had any processing done to it, other than creating the file itself. A JPEG file however has an amount of processing done when the image is taken and saved to the memory card.

And this processing of the JPEG cannot be undone. It is baked-in. See back to the cooking!

Sure you can do further processing to a JPEG image but what is done in camera is done.

Is there more than one JPEG file format?

No. JPEG is universal.

Is there more than one RAW file format?

Yes. And that is the point. Each camera manufacturer has their own RAW file format.

And this is where DNG comes into play.

Why did Adobe create DNG?

Quite simple. Each camera manufacturer has its own RAW file format. Now I use two camera systems, Canon and Olympus. They have different file formats.

• A Canon RAW file has the file extension .CR2
• An Olympus RAW file has the file extension .ORF

So what? Does this really matter?

Well I have all my photos in a folder in Lightroom, and Lightroom reads both file formats just fine. This has not caused me a problem. To date.

So working in Lightroom and Photoshop I don’t have any problems as I am.

But in the future?

I get their (Adobe) point. They refer to DNG as “The public archival format for digital camera raw data” on the web page Digital Negative (DNG).

And not all software can read all file formats. So there might be problems in the future.

Going back to the Adobe website

“Digital Negative (DNG) is a publicly available archival format for raw files which are generated by various digital cameras. This addresses the lack of an open standard for raw files created by individual camera models and ensures that photographers easily access their files.”

I am more than happy to quote them as they know this stuff better than me!

So does DNG affect image quality?

If you dive deep on the internet you will find lots of reports of loss of image quality.

But my understanding is that the conversion is lossless, whilst the conversion creates a new and smaller file. That is my take on DNG.

So again, to be clear, DNG does not affect image quality.

Is there any reason to not convert to DNG?

Well if you stay in the Adobe ecosystem you will be just fine. If you do not there might be apps out there that might not read DNG.

What do I do?

I use the RAW file formats on my Olympus and Canon cameras. They both sit happily in Lightroom where I do most of my processing.

How does this affect my architectural and construction photography work?

It doesn’t at all as I use both Canon and Olympus RAW formats quite happily, and issue images to clients in the universal JPEG format.

Should we convert our RAW files to DNG?

I do not see the benefit in converting to DNG, not that there is anything wrong with doing this. Not at the moment anyway.

But

If every camera manufacturer agreed to use DNG then I would happily switch over right now and not give it another thought.

I guess my conclusion is that it does not matter greatly to me either way right.

So lets’ not worry about this – we all have a little bit more knowledge now and one less potential thing to worry about which frees us all up a little bit to concentrate on the important stuff namely creating great photos.

Further reading

I like to finish my blog posts with something related that I think might be of interest to you. These two fit the bill nicely.

JPEG file format: The what, the how and the why

21 Reasons I Shoot in RAW but Share in JPEG

And I like this post too so why not give this one a go?

21 photography tips that make an INSTANT difference

Summary

We now know more about the different camera file formats, and if we should use the DNG file format or not. And if we do what the consequences of this are.

And we know not to worry about this too much, leaving us to concentrate on more important stuff like getting out taking photos.

Thanks for reading this post which I hope you found helpful and informative, and answered the question of course!

Rick McEvoy Photography

#dng #dngimagequality #imagequality #photography #camerafileformat