Jpeg export is low quality

Question

For some reason, when i export a jpeg, it seems low quality, even if i go up to 12 quality (and make the image 3 times the size of the original)
here's an example, an image that was TAKEN as a jpeg originally, imported to aperture, and then exported after some editing.
the one on the right is the exported jpeg, and it seems ..not sharp at all
http://i24.photobucket.com/albums/c44/funk11963/Picture1.png
I'm not the only one with this issue, check out this post where other people have the same problem.
http://www.apertureprofessional.com/showthread.php?t=15206&highlight=resolutiononexport

Answer 1

FUNK1196 wrote:
For some reason, when i export a jpeg, it seems low quality, even if i go up to 12 quality (and make the image 3 times the size of the original)
here's an example, an image that was TAKEN as a jpeg originally, imported to aperture, and then exported after some editing.
the one on the right is the exported jpeg, and it seems ..not sharp at all
http://i24.photobucket.com/albums/c44/funk11963/Picture1.png
You've got a couple of problems here:
1. JPEG is not a very good format for editing then re-saving as a JPEG. It's a lossy compression, and one of the cruelest ironies is that compression artifacts compress poorly. It can get especially bad if you open an edited JPEG and re-save it to a third JPEG. Obviously, at the higher quality settings, you lose less in each step, but you'll still lose something.
The best strategy is to shoot your pictures using Camera raw, which should be either uncompressed or compresses with a lossless scheme, or in an uncompressed format like TIFF. Then, edit them and do all your work with the TIFFs or the raw files. Once you're happy with your edits, then the last step is to export a JPEG. If you want to make a new version of the picture, just go back to the original, make a new version (either from the master or your previously edited version), edit that, and re-export when you're done.
2. Exporting at a size larger than the original will always result in some image degradation. Think about it this way: if you printed your JPEG on a sheet of rubber and stretched it to three times its size, your picture would get blurrier the more the sheet stretched. The same kind of thing happens in your computer. You're always better off to work on a picture at a bigger size than you'll eventually need it, then make it smaller when you're done editing.
I'm not the only one with this issue, check out this post where other people have the same problem.
http://www.apertureprofessional.com/showthread.php?t=15206&highlight=resolutiononexport
What they're talking about in those posts is different. They're talking about a resolution setting for printing. For example, suppose you have a picture that's 1500 by 1500 pixels. If you print that at 300 pixels per inch, you can print that picture 5 inches by 5 inches. If you change the resolution to 150 pixels per inch, the same 1500x1500 pixel picture will print out 10 inches by 10 inches. But if you look at the picture at 100% zoom level on screen it should look the same, since the screen has a fixed resolution.
This article might explain it a bit better:
http://www.ransen.com/Articles/DPI/Default.htm
charlie