Long term archiving of images? DNG? Or maybe just JPG?

[Jonathan Levin]

I started a thread on this a few years ago I think but I can’t locate it so I’ll start again. I’m also not certain if this is even the right forum. If it is not, please tell me where this should go.

I’ve been struggling with this for several years now and I’ve concluded that maybe the best option for archiving for me is to save all my images as JPG.

Let me explain. Initially I was happy about archiving Nikon Raw files (NEF) as DNG (Camera RAW). Anything I shot as JPG will remain in that format. I made my corrections, crop, and other adjustments so that the images look very close to what I would hope if someone other than myself were to open the file. I did all this in Bridge>Open in Camera RAW… then saved file(s) as DNG. I then deleted the NEF files. All fine so far.

I then found that if I open one of these saved DNG images in something other than Photoshop/Bridge i.e. Affinity, Apple Preview, Apple Photos etc., none of my changes are reflected in any of those programs. Not reading Adobe’s meta data/xml? Please try this and maybe you will see what I’m talking about, or else I’m an idiot and doing something wrong.

This is troubling and the only way around this is to open all those DNG images either in Bridge or Photoshop where they look as expected. That fine, however that means I would need to include some sort of “Read Me” (remember those?) about only opening in B or PS. At best I’m assuming someone would be able to use PS they would need to subscribe to the Adobe plan, and know how to use PS.

16 bit TIFf files are just too big, so I started thinking about saving everything out as the highest quality JPG which I know will look similar cross platforms, apps, browsers, etc. I know I’d lose my 16 bit info since JPG is 8 bit as well as the editing flexibility of DNG. But at least they LOOK close to what I’d want.

I also think that there is a greater chance of something being able to even open a JPG in 25, 50, 100? years from now.

I’m thinking long term when I’m gone. I just don’t want any of my images to look like the un-edited versions. Maybe I am thinking about this all wrong, but I thought that with the adjustments, crop, etc. that I do in CR would appear the way I intended using any photo editing app. I just don’t want to leave the guess work for correction up to anyone else. On the other hand maybe, no one will give a crap and never open any of my stuff.

[Jonathan Levin]

The headline Should read  "Long Term Archiving...." Not "Long Term Arriving..." Sorry.

[Rikk Flohr: Photography]

I fixed it

[TheDigitalDog]

The edits are not seen because they are proprietary metadata instructions to render the raw. The edits in JPEG is destructive and baked into 8-bit per color data.

Ideally you want to stick with the raw data. The JPEG engine that processes the raw massively clips and compresses highlights. We often don't when editing the raw. This compression can clump midtones as much as 1 stop while compressing shadow details! People incorrectly state that raw has more highlight data but the fact is, the DR captured is an attribute of the capture system; it's all there in the raw but maybe not in a camera proceed JPEG.

A raw capture that's 10 or 11 stops of dynamic range can be compressed to 7 stops from this JPEG processing which is a significant amount of data and tonal loss! So when we hear people state that a raw has more DR than a JPEG, it's due to the poor rendering or handling of the data to create that JPEG. The rendering of this data and the reduction of dynamic range is from the JPEG engine that isn't handling the DR data that does exists as well as we can from the raw! Another reason to capture and render the raw data, assuming you care about how the image is rendered!

DNG like it's cousin TIFF is an openly documented file format. 

[Jonathan Levin]

Ok. Thanks for that. I am aware of JPGs shortcomings overall. BUT, what I am considering is making adjustments, crops, etc. to the file RAW (DNG) first. Get it to a place that I LIKE, and then in Camera RAW save tht out as a high quality (12), full dimension JPG file. The problem is when and if someone gets one of my DNG files, their interpretation of how it should look might be totally different than mine on my nicely calibrted system. At very least the file is ready for web, print, whatever, and no one has to have a copy of PS, Affinity, or any other photo app to at least see what I had in mind. 

[TheDigitalDog]

A fully rendered JPEG can be stored in a DNG and extracted from the raw in the DNG. Best of both worlds.

[Jonathan Levin]

So I wonder what would the point be to save a JPG as a DNG? Certainly not editing capabilitys. WHy best of both worlds???

[TheDigitalDog]

Raw which can non destructively be edited AND a JPEG of that current rendering. Best of both worlds. No data loss (raw is raw). No baking of edits (parametric) in openly documented file format!

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

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

https://www.dpbestflow.org/dng