download full resolution photos from iCloud

Hey there jixiong,

Follow the steps below to help with downloading full resolution images from iCloud:

On your Mac or PC

1. On iCloud.com, click Photos and select a photo or video. Hold the command key on your Mac or control key on your PC to select multiple photos or videos. 

2. Click and hold the download button  in the upper corner of the window. If you want to download your photo or video as it was originally captured or imported, choose Unmodified Original. For JPEG or H.264 format — including edits, and even if it was originally in HEIF or HEVC format — choose Most Compatible.*

3. Click Download.

If your photos download as a ZIP archive, learn how to uncompress the folder on your Mac or your PC. 

For more details: Download iCloud photos and videos - Apple Support

Take care!