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View Full Version : EXIF : what is it and how is it relevant to my photography?



ricktas
01-01-2014, 7:48pm
We often see posts regarding EXIF (or properly Exif)and I thought it might be worthwhile creating a thread detailing what it is, how we can access it and once we get a good amount of information in this thread, we can copy and edit it into an article for our New To Photography Library section.

So first up, what does EXIF mean?

EXIF is Exchangeable Image File Format. It is a standard that details the image format, camera settings and more for digital images. it is basically metadata (information) about the digital image. EXIF data can also be found in digital sound files (music etc)

What sort of information is contained within EXIF?

Information stored within an image file tells us more about the actual digital image. It can include information like what camera brand and model was used, what date and time the photo was taken, what mode was used (auto or manual) and more. EXIF data can contain a huge amount of information about the digital image. EXIF is created at the time the image is captured and embedded inside the image file itself.

What else can EXIF contain?

EXIF can contain a lot of information. It can contain all the setting information from the camera at the time the digital image is captured, and in some cases even GPS geolocation information and more. What EXIF contains is entirely up to what the camera manufacturer decided to allow in the camera programming. Some of the usual information, is camera make, model, date and time of image capture, camera settings used, if flash was used, what camera mode was used (auto/manual), what lens was used and what focal length it was set to, what colourspace, and a heap more.

Why is EXIF needed?

At the very base level EXIF provides us with detailed information regarding the digital image file. Understanding and knowing EXIF is not neccesary for viewing photos. We can enjoy photographs without knowing anything about them, other than the visual appeal of the photograph itself.

However EXIF becomes an interesting inclusion in our digital image files when we seek to understand more about the image file. Probably at the pinnacle of this would be police forensics. EXIF data can be used in a court of law to determine the exact time the digital image was captured, and if the camera has GPS, even the exact location it was taken. EXIF can prove the exact time a bomb exploded or that a particular person in the photo was present at a particular place on a specific date and time.

For photographers though, EXIF can provide valuable information regarding the digital image and allow others to assist solve a problem/issue that the photographer may be experiencing in their photography. It can tell us things like shutter speed, ISO and aperture. What auto-focus mode was used, if flash was fired, and more. All this information can give the viewer valuable data that can assist in helping resolve the 'problem'.

EXIF can be invaluable when providing Constructive Critique of a photo on Ausphotography or other forums, or with a photographic mentor.

So how can we 'see' EXIF data?

To view EXIF data we can use photo editing software like Photoshop, Lightroom, Aperture etc on our computers. Or to view EXIF on photographs displayed on the internet we use an internet browser 'add-on'. Add-ons are small programmes that can be added to our browser software to enhance the capability of our internet browser.

To find an add-on for your browser, simple google search 'EXIF add-on for ...." replace the dots with your browser. IE Internet explorer, Firefox, Chrome, etc. When you find one download and install it.

Once installed, most add-ons are accesible using right-click. When you find a photograph you want to find out more information about, right-click, and from the pop-up menu choose 'EXIF data' or 'view EXIF" etc and you should then be able to see the additional information.

EXIF data can be stripped or removed from a digital image file. This can be done on purpose or inadvertently. So some photographs may say 'no data available' when you try and access the EXIF data. So if you cannot view EXIF it does not mean there was not any, just that it has been removed by some means. In this instance, if possible, you can always ask the photographer for their EXIF information.

*** If any member wants to add to the above, or suggest and edit, please feel free to do so below. Once we get it tweaked, and possibly include photos with EXIF, and screen shots of their EXIF, etc. I will turn it into a Library article. ***

Sdison
02-01-2014, 6:27pm
I use Google Chrome and I use Exponator (https://chrome.google.com/webstore/detail/exponator/npdclakkbcpndnjlnajapdlbdncpijdg). It's fantastic - it allows you to fully customise the EXIF display on mouseover to show all the details you like.

Kym
02-01-2014, 6:55pm
Firefox Exif addons
http://araskin.webs.com/exif/exif.html
https://addons.mozilla.org/en-US/firefox/addon/fxif/

Jhead stand alone Exif tool (which our comp system uses) - this one can extract Exif and remove it from a JPEG yet not change the JPEG image
http://www.sentex.net/~mwandel/jhead/

ricktas
02-01-2014, 7:27pm
thanks guys. All these posts help so I can eventually build a good article in the site library about EXIF

Mary Anne
02-01-2014, 10:10pm
Using Firefox I have two Add-ons.. Exif Viewer and Exify which is a mouse over if you just want the basics.