EXIF Maker Notes

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This article describes the various kinds of EXIF and EXIF-like metadata contained in digital image files and how you can display and use this information in IMatch.

EXIF Meta Data

The EXIF meta data Standard describes how cameras and other imaging devices can embed information about the image inside the image. Useful EXIF information like Aperture, Shutter Speed, ISO, Date/Time etc. may be stored in images taken by your camera and can later be displayed by software like IMatch. EXIF is usually meant to be written by the camera or image device. It is not the preferred way to store meta data in an image (see XMP™ and IPTC for the preferred standards)

EXIF Maker Note Mysteries...

The EXIF standard allows camera vendors and others ("makers") to add proprietary data to the EXIF record stored - the so-called maker notes. This data area is not standardized and hence each camera vendor stores different information in this area. Unlike the EXIF data itself, maker notes are undocumented and proprietary. Camera vendors do not document the information they store inside the maker notes and usually each camera model has different information stored at different places inside the maker note data area.

Unfortunately, camera vendors store important information inside the maker notes, like the ISO settings you had dialed in, the lens you used and other relevant data. Why they don't use the reserved fields inside the official EXIF record for that purpose is a mystery to me. One reason may be that they do not want other software to be able to decipher and display this information.

IMatch goes a long way in order to decipher and extract as much of the maker notes as possible. In addition to the full EXIF 2.2 standard, IMatch knows about 500 different maker notes from different camera vendors and can display the information. But it is hard. Camera vendors usually do not provide any support to developers, and if they do, they don't do anything in the maker note area. The huge number of new cameras which hit the market each year (about 150 to 200 new models per year) and the ever-changing maker notes make it hard to keep up with all the changes.

The EXIF Editor

The IMatch EXIF editor allows you to view all the EXIF data and maker notes contained in your images, and also to modify the date and time and orientation (which are the ones which are safe to modify. Some users have coded scripts which write other EXIF info, but be sure you know what you are doing before using them). It also supports the proprietary meta data used by some camera vendors instead of EXIF, or in addition to the standard meta data. The editor combines these different pieces of information and presets it in a unified format, using colors to separate the different pieces of information.

To load an image into the EXIF editor, just select the image in a thumbnail window and press the EXIF button in the toolbar above the thumbnail window.

The EXIF Property Window

The EXIF property window below the thumbnail window allows you to display EXIF information. This window is fully customizable and allows you to display the EXIF fields you are interested in. The User property windows can also display EXIF information if you want.

To define which EXIF fields you want to include in the property window, use the Customization features available for property windows. See the IMatch help for more details.

EXIF Variables

The universal IMatch variables give you full access to all EXIF fields for an image using the syntax

{Image.EXIF.Name of the EXIF field}

For example, to access the EXIF maker note "nik Lens Data" available for Nikon digital image files, use

{Image.EXIF.nik Lens Data}

To get the names of the EXIF field and maker notes available for your images, please check the EXIF editor. Use the field names exactly as displayed there. Use Copy/Paste to copy the EXIF field names from the editor, for example. EXIF variables can be used in property windows, tooltips and the info window and tooltip in the IMatch slide show. You can also use variables in the Contact Sheet Builder, Batch Processor and Smart Renamer to retrieve and display EXIF information.

Note: When you refer to an EXIF variable using {Image.EXIF....} IMatch will always retrieve the data from the original image or off-line cache. Use the corresponding XMP variable {Image.XMP....} to load the EXIF data from the database cache. This is much faster and also works for off-line images.

Sort Presets

To sort after a specific EXIF field, use the corresponding XMP field in the sort preset. Just scroll down until you find the field you want to sort your images after. To create / edit Sort Prestes, go to Options > Sort Presets in IMatch.

Data-driven Categories

You can use the data-driven categories feature in IMatch to automatically categorize images using EXIF information. This for example enables you to group image by date and time, camera or lens used and much more. Please see the IMatch documentation for more information about data-driven categories.

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