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Managing Digital Image Data

There are many magazine and web articles available which offer advice on handling digital image files from camera to finished image. Most of this information concentrates on establishing an image conversion and processing workflow that yields the optimum image from the original digital file. In addition to image information, files from most digital cameras also contain a great deal of information relating to the conditions used to record the image. This EXIF (EXchangeable Image file Format) data contains basic exposure settings (shutter speed, f-stop, ISO setting) as well as supplementary information (date/time, exposure metering mode, exposure mode, lens focal length, focal distance and more).

The Canon camera which I use for most of my photography store 25-30 parameters in EXIF data, the actual number depending on the number of custom programs (mirror lock up etc.) being used. In the old days I might have recorded some of this information (probably only shutter speed and aperture) in a notebook when I took the image, but often I forgot or couldn't be bothered, and when I did remember, it was often difficult to match the data to images when the films were developed. Now all this useful information is embedded in the image files coming from the camera and can't be lost. However handling this information efficiently and retaining information linkages between the original file and a processed image still requires some discipline in operating a standard workflow between camera and archived image. The workflow I currently use is described below as a guide, but can be readily adapted depending on your camera and available software. If images are captured as JPEGs, steps relating to RAW file conversion obviously do not apply, but EXIF data is handled in the same way.

 

Data workflow

1.  All images are copied from memory card(s) to a new folder on computer. I generally use one folder for each days shooting, and this folder will eventually contain subfolders for the raw images (RAW), RAW to TIFF conversions (CONVERTED) and final images after adjustment in Photoshop (COMPLETED).

2.  Image files are previewed in BreezeBrowser (www.breezesys.com).  Any unwanted images or exposure mistakes are deleted and portrait format pictures are rotated to the correct way up at this stage. 
3.  Files to be worked on are selected and RAW files converted to TIFFS. Converted images are marked for data export by tagging.
4.  Once all images are converted, tagged images are selected and EXIF data exported to a delimited text file. This produces a single file containing all image EXIF information in column format which can be imported into a spreadsheet. 
5.  The text file is opened in Excel and unwanted data columns (camera serial number, firmware version etc.) are deleted. This leaves a spreadsheet page with summary data for each converted file. The Excel file is saved in the same folder as the image subfolders.

6.  Converted images are now opened in Photoshop and processed as required. Finished images are saved into the COMPLETED folder as 8bit PSD files, retaining the original image number in the file name. This allows all finished pictures to be tracked back to the corresponding original camera file.
7.  When all the images have been processed, I use PrintFolder (www.no-nonsense-software.com), a freeware utility which can be used to list details of files in a folder, to copy file information into a second spreadsheet page. Since the files names have retained the image numbering of the raw files, the file order on this page is identical to the page with exposure information. The spreadsheet file now contains all the information I need to identify the source of images and to easily find all the exposure and technical data I need at a later date.

8.  Once I'm happy that all is in order, I generally delete the CONVERTED subfolder as the large TIFFs take up lots of disc space and these files can be easily regenerated if required from the files in the RAW folder. 
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