Photo quality when saving to usb flash drive

Myselfhello wrote:

I have an iPhone 13. If I copy photos and videos from my iPhone to a usb flash drive after saving them to files will the quality be the same as the original in the photos app? Do I need to click on anything to ensure they stay the original quality? I don’t want them of lower quality to save space.

That's a really good question, and rather complicated. I just used "Save to Files" and that produced an image that had the same resolution as the original and was, I think, indistinguishable from the original. Bu the saved file was a smaller file size, so that might add some confusion. Picture files can be compressed. A picture of a Blue Sky may have just as many pixels as a picture of Aunt Ethel at the Grand Canyon, but the blue sky doesn't have much information in it, and it can be compressed into a smaller file. So the file size isn't necessarily a measure of quality. HEIC files, for instance, are compressed into smaller sizes for the same quality as a jpg. I'd say that, for all practical purposes, the saved file is the same quality as the original.

That said, it is also true that Photos Library itself has way more information in it (like faces, for instance) than is exported.

Myselfhello wrote: … The problem I am having now is when I plug the flash drive into the laptop the videos only play sound no picture.

Videos are their own problems. I just "Saved to Files" an iPhone video to a disk drive and then played it on my computer, and it was just fine, sound and all. But movie files aren't entirely standard, so if you're not running a recent OS, there might be trouble. I played my video on my Mac with Quicktime Player and also with VLC, and both apps worked equally well.

If you are using iCloud Photos and "Optimize iPhone Storage", that might raise a question.

Suppose that your phone is currently storing a photo in a reduced-quality, "space saving" format, and you go to export the photo to Files. Would that cause the phone to download the full-size copy from iCloud before doing the export? Or would it export the "space saving" version?

iCloud Photos always stores full-size copies of photos in iCloud itself, and there is an iCloud Web interface. Thus, if you were to log into iCloud from a Web browser, and download copies of photos from there, you would get full-size copies. (I think you would have to choose between downloading the original copy or downloading the edited one – Photos likes to keep original and edited copies together, which adds a little wrinkle to exporting.