Open Photography Forums  

Go Back   Open Photography Forums > Digital Darkroom > Image Processing and Workflow

Image Processing and Workflow RAW, DNG , TIFF and JPG. From Capture to Ready for Publish/Display. All software and techniques used within an image workflow, (except extensive retouching and repair or DAM).

Thread Tools Display Modes
Old January 30th, 2007, 07:05 AM
samdring samdring is offline
New Member
Join Date: Jun 2006
Posts: 17
Default Writing to raw

Everywhere I look (although I am yet to spot it here) people are warned away from writing to raw. I do not use dng but demand that all exif, iptc etc is written to raw and subsequent versions so that I am totally independent of any database in any dam software and, indeed, upon any corruption can re-create such a dbase within minutes directly from ALL my images. I do not like sidecar files. I shoot 100% raw and regularly use a range of converters (RSP, Lightroom, Canon's DPP and Adobe etc) and have 'trialled' some others. All raw files are downloaded with annotations written to those raw files either through Downloader Pro or IdImagers Downloader. I have never encountered any problem caused by this approach.

Question please: Has anyone had a problem caused by writing to raw or is the well published warning somewhat OTT?
Reply With Quote
Old January 30th, 2007, 08:55 AM
Cem_Usakligil Cem_Usakligil is offline
Senior Member
Join Date: Jun 2006
Posts: 5,946

Very good question, Samdring. Don't I know you from incidentally?
Nevertheless, I too am looking for an answer to this one. I can't imagine why one would have any issues with RAW corruption if the format of a certain camera manufacturer is well known, such as my CR2 files for Canon. Go figure!


Kind Regards, Cem

Reply With Quote
Old January 30th, 2007, 10:17 AM
StuartRae StuartRae is offline
Senior Member
Join Date: Jul 2006
Location: Wiltshire, UK
Posts: 1,024

Hello Sam,

I don't think it matters at all if you write your own Exif to the RAW file. What does matter is if the existing Exif is changed.

The Exif can include data pertinent to the image - WB, exposure, f-stop, etc. to be used by software that can take advantage of it - usually only the manufacturer's own conversion software. Once this is changed, in effect the image is changed.

Third party converters don't in general honour this Exif, so for example it won't effect the conversion by RSP. You will however remember that in the early days of RSE, files which had passed through Nikon software crashed it because the file was 'non-standard'. Canon DPP also changes the RAW file, although AFAIK this never caused any problems.

I prefer to keep my RAW file as it came out of the camera, or at least make a backup of the virgin data.


Reply With Quote
Old January 30th, 2007, 10:32 AM
Asher Kelman Asher Kelman is offline
OPF Owner/Editor-in-Chief
Join Date: Apr 2006
Posts: 33,545

So, Stuart, does conversion to DNG, as promoted by Peter Krogh and others, keep the original MFR's data or is something lost?

Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are Off
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -7. The time now is 08:22 PM.

Posting images or text grants license to OPF, yet of such remain with its creator. Still, all assembled discussion 2006-2017 Asher Kelman (all rights reserved) Posts with new theme or unusual image might be moved/copied to a new thread!