So I've been spending a lot of time trying to get my photos all organized in Flickr. One thing I found really annoying is that the windows preview program doesn't auto-rotate your pics when you view them if they're vertically oriented, which can make it awkward to really see how good a photo is (especially compared to a horizontal shot of the same thing).
Of course most online sites rotate them automatically. I found a pretty good summary of the orientation flag here:
http://www.impulseadventure.com/phot...ientation.html
It seems like rotating is a really minor little detail but it actually turns out some programs will screw up your photos if you rotate with them.
Here's the cliff's notes:
1) Window's Picture Viewer will wipe out your EXIF data if you rotate a picture. It immediately saves over the old photo when you rotate rather than just rotating it on your screen and giving you the option to save later, and for some reason it doesn't bother to keep the metadata on the picture (like the timestamp when you took it, the orientation flag, camera and exposure info, etc). So be really careful when using Windows Picture Viewer, or just avoid it!
2) Irfanview is a nice viewer for photos, with more options than Windows Picture Viewer. There's an option in the properties to auto-rotate based on the orientation flag. Its also completely free.
3) You can get simple little programs that will rotate your images so they're all the right orientation by default. You just point them at a folder of files and it looks for anything that isn't right side up by default and rotates it (or you can use them when initially copying from your camera to your computer to do it at that time)
4) Not every program can rotate without losing some image detail...so check before you use a program to rotate an image to make sure it can do lossless JPEG rotation.
Photo orientations
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