One of the things to do before buying a camera is to check out sample photos taken by the camera and lens combination. It’s as easy as doing a Google Search these days. Come to think of it, one of the more hands-on ways to learn about the art and science of photography is by looking at photos and the data that comes with it.
The data that comes embedded (usually) with every digital photograph is called EXIF. The Exchangeable Image File Format is a bunch of meta-data (data that describes other data) or a standard format for storing information about a digital image file. It is also simply written as Exif and can be found on JPEG image files, and also on RAW and TIFF image formats. The good thing is that the data is easily viewable and understandable. Both of these give us the best ‘learning tool’ for photography.
How Does EXIF Look Like?
If you don’t know how something looks like, you won’t really understand it. Here’s how EXIF data looks like for any photograph:
How did I get this? Well, it’s as commonly available in your own computer as in any other. Click a photo (or take one that’s already clicked) — right-click on the photo to go to its Properties – click on the Summary (Win XP) or Details (Win 7) tab. In Mac OS X, you can also open the photo in Preview and choose Show Inspector (Command+I).
A single glance shows you that Exif data is nothing but a complete description of the photograph in terms of its physical characteristics – width, height, resolution, and other camera specific information like shutter speed, aperture setting, ISO setting, flash, the focal length and much more.
A site like Flickr also displays it under its Actions menu:
As each camera writes this data differently, sometimes some information may be there, sometimes not. For instance, data and time may be missing in some cases or location info if geotagging is disabled. But rest assured that the data available usually is sufficient to understand how the photo was composed.
What Are The Ways We Can Use To Look At EXIF?
In brief – more ways than I can mention here. Apart from the Properties tab of the image itself in your computer, here are some more:
- Adobe Photoshop /Adobe Lightroom
- IrfanView (with EXIF plug-in)
- Free online viewers (e.g. Jeffrey’s EXIF Viewer)
- Firefox Add-ons (Exif Viewer)
- Chrome Extensions ( )
- Google Picasa
…and the list goes on.
My fellow author Tim Brookes has also gone into the details of What EXIF Photo Data Is, How To Find It & How To Understand It .
He covers the basics of Exif data completely. Now, let’s look at how we can use it to improve our photography using Google Picasa.
Making Sense of Exif for Perfect Photos
I am going to use Google Picasa to check the data on camera settings that’s stored inside each photo…and hopefully learn a bit while ‘stealing’ from the skills of others. You can view Exif data by opening the Properties panel of a photograph as seen below. Select the photo – by default the Properties panel should be displayed – if not, click on Picture > Properties. You can also click the Show/Hide Properties Panel button to view the metadata. Plus, you can also right-click (Windows) or Control-click (Mac) a photo and select Properties (Windows) or Get Info (Mac) to open the Properties panel.
Note: You can view all the Exif data in the software. If you upload any photo, Picasa will remove any and all Exif information except for the location information.
Here’s what Exif tells us about an image:
- Camera Model & Make: The camera is a Nikon Coolpix S210.
- Date and Time when photo was taken: If this parameter is disabled from the camera, the date and time is not encoded into the photo. Some cameras also come with geotagging which adds the location too.
- Exposure settings: Learning about exposure and how one slight change in one setting affects the others is one-fourth of your camera education. The F-stop indicates the dimensions of the aperture – for instance, each decrease in F-stop is in turn a decrease of light by half of the previous intensity. The aperture is at the wide end in this case, leading to a greater depth of field.
- Shutter speed and ISO: Exposure also depends on shutter speed and ISO numbers, both of which are indicated in the Exif data. Being an automatic compact camera, the exposure time is short at 0.003 seconds. A longer exposure time in whole seconds generally indicates the use of a tripod to negate hand vibrations on the camera.
- Use of flash; Exif data also shows if flash (artificial light) was used or not.
- Focal length: The focal length of the camera is similar to that of a normal film camera. Being an auto-focus camera, the image has lesser definition in its colors.
The basic principle of photography is about composition i.e. how the picture is set up. Exif doesn’t help in that, but then that’s why the picture is open in front of you and observation gives you factors like angle of view. If you understand the angle of view, you can estimate the type of lens you will need to replicate or better the shot.
Picasa also displays a histogram – though not part of Exif data – which is a bar chart plotting how the pixels in your image are distributed between dark and light. You can adjust the colors of your image using the histogram in a full-fledged photo editor like Photoshop.
Understanding Exif data would be a bit too much to expect from these brief points. Let it suffice as an introduction to the Picasa way to read Exif data of your photos. The one true benefit of knowing the bits and pieces of Exif is that it will give you the confidence to move away from automatic scene modes of your camera and experiment with manual options.
Are you exploiting at Exif data as a free photography lesson? Or are you leaving the figures alone and going by gut feel and a good eye? Show us your thoughts.