Software
Some software does not utilize the orientation tag written by the camera. If you suspect this is the case, don't rotate the photos, but try viewing them straight out of the camera with an up-to-date free program such as Picasa, XnView, or FastStone Image Viewer. I have personally verified that these programs display photos according to the embedded orientation flag. If these programs display the photo at the proper orientation, then your original software is at fault and you should consider updating or replacing it.Ideally, you want a program that will utilize the orientation tag for display only, and not alter the actual data of the file. However, if you want to ensure that your image is always shown at the correct orientation, no matter what software you use, the best way is to use a program that will rotate the actual content losslessly based on the orientation tag, then update the orientation tag to reflect the new orientation. (Microsoft's free Windows Live Photo Gallery does this.) This will ensure that programs which do use the orientation tag will display the image properly, as well as those that do not utilize the orientation tag.
Here are some of my findings on some popular programs, and how they handle rotation issues.
- Windows Explorer does not utilize the orientation flag to show thumbnails, even in Windows 7.
- Windows Picture and Fax Viewer (included with Windows XP) is one program that is notorious for not honoring the orientation flag. Additionally, it will remove any existing orientation flag, along with other metadata, as soon as you rotate a photo using this software. [reference]
- Windows Live Photo Gallery will re-orient your pictures based on the orientation flag in the file, but only when importing photos directly from the camera. This is an import option which is enabled by default. Windows Live Photo Gallery does not utilize the orientation flag stored in the image file to display photos properly when they are already on your computer. Additionally, if you rotate a photo, the actual content is rotated and a new orientation tag is saved into the file by Windows Live Photo Gallery.
Older Cameras
If your camera is older, it might not have an orientation sensor. If you suspect this is the case, you can use a program to view the EXIF data of the photos before doing any editing in another program. You want to be sure that the program you use is showing ALL the EXIF information and not just the fields it thinks are important. You can use a dedicated EXIF viewer for this, but XnView works well, is free, and is good to have for many different things.• How to View EXIF Data with XnView
Once you have established that your camera is NOT writing the orientation tag, you can safely rotate the pictures in your preferred photo software. If the software is current, it should add the proper orientation tag to the metadata and you won't need to worry about the picture displaying sideways if you edit in another (current) program later or if you post the photos online.


