William,
First, camera raw files remain unaltered. The changes you make are either stored in a file accompanying the camera file, a so called "sidecar file", or stored in a central database on the computer.
Whether the former or the latter depends on a setting in Preferences.
Raw files themselves are read-only by definition.
This implies also that changes made are non-destructive and redoable.
I would switch off all automation in ACR, ("as shot" setting) and right after (or during) ingestion make a backup.
I keep camera files on two separate, not normally connected storage drive arrays (one camera raw, one DNG conversions), and two sets of CD-ROMs in DJ boxes on different locations.
Completed/Client projects are stored on a third disk array/CD cabinet.
The funny thing is, with negatives, although more vulnerable, I was never that paranoid.
Rob
Yeah I know what you mean Rob, I took the digital jump about a year ago, I was never this paranoid about my negatives either, one copy to work with, one set in the fire safe.. all done. LOL. So am I to understand that when I save a set as DNG the "altered" information for them is in a sidecar also, so therefore they are as "editable" as the original raw file?
No, sidecar files are added to Camera raw files, but DNG files have their settings embedded.
But again, nondestructively. when for instance you deliberately turn up exposure in ACR, thus blowing highlights sky high, then save as a DNG, then opening that DNG the exposure slider is still high (still blowing highlights), but since the settings are embedded, rather than applied, you can pull the slider back again to restore highlights.
Important to understand is this: the image data is never altered (neither in CR2 nor DNG) , the embedded settings are a mere set of instructions for the raw converter how to render the file into image pixels.
The in-camera recorded data is never lost.
And again, if you want to retain the interpretation of the camera (irrelevant, as it’s only tagged to the file) set ACR to do nothing.
Rob
Right Rob thats exactly what I am talking about, but exactly what is "nothing" when I have camera RAW set to "defaults" and I have the "auto" turned off in preferences. I open a file in RAW and most things are zero’d but the contrast is +25 the blacks are +5 sharpening is +25 and brightness is +50. for example when I KNOW a file was exposed correctly in camera and open it in RAW these settings are already applied and the pic looks right, if I slide the contrast, brightness etc back to 0 then the pic is way dark.
And in reguards to the DNG being saved "with the exposure turned up" if I open it in my CS3 where the "sliders" dont nec match, is it still editable back to the original settings?
William,
You have to understand that a camera file is not yet a photo. the sliders at "default" are arbitrary.
The point is that you archive everything your camera captured when you archive the Raw file
You might as well ask "I have this very important manuscript that I want to archive unaltered, but someone attached a note to it with a paper clip. How can I be sure that the original is not altered".
Just archive your camera files. I strongly advise you to do some reading on Raw (Google)
Rob
I understand that Rob and thanks for your help, I guess my question is, using the manuscript analogy, when I save my "manuscript" to DNG is it just as "unaltered" as the original raw file? So basically is opening a DNG file the exact same starting point as opening my CR2 file from the camera (of course given no adjustments were made, since they are arbitrary anyway)?
When i work on a dng file and finish a photo, i save the finalized version as a tif file and then i also save the original dng file right next to it by name,so if i ever need to rework an image,it is burned right on the dvd with the finished version. so if i have sunset.tif,i also have sunset.dng in the same folder for easy retrieval.
