where to download images to ?

That's true - if you need to be viewable from the browser you'd either have to:

1. create a controller/method to load the file and send it to the browser. This has the benefit of allowing security checks, URL rewriting, etc, if needed, but at the cost of another full page hit on your application for all of those images, which may be too steep of a drawback.
2. Create a symlink to the writable/uploads folder on your server. This also may or may not be ideal for your uses.

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