Hi!
I have been able to upsize jpg files quite well using Camera Raw -- but as Conrad said below it is a little tricky to find. If you open a jpg using Filter>Camera Raw, the Enhance option is not even visible in the menu, but here is a trick that I learned.
In your Open dialog box, select the image you want to enhance. Once you click on the file name, such as xxx.jpg, down at the bottom of the panel you will see that in the Format drop down menu, it says jpg. Change that to Camera Raw, and click ok. Once the jpg opens in Camera Raw, right click on the image, and the Enhance Feature will be available. Then you can use it on that specific jpg.
I find that it has worked well for images I needed to enlarge.
The key is to remember to change the Format dropdown menu and not the Enable drop down.
Michelle
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