I just went and looked at photos I’ve taken recently and couldn’t find one over 2 MB. Granted I’m only on the 11 (fellow PWM sufferer). Do you think I could have something jacked up in settings? I only use the default camera app.
Not at all. 800kb to 10MB is completely normal.
A photos file size that is transcoded using a lossy compression format will be determined by the original size of the file, the type and efficiency of the compression being used and that files overall complexity (its resistance to be compressed).
Since we are using lossy compression (HEIC and JPG in this example) for a photo the balance is going to be file size vs image quality. In photo editing software you can set the quality of the transcode yourself to your preferences like this....
Notice the lack of return on investment when comparing the quality settings from quality = 0 to quality = 80. The file size the same. Increasing passed 80 is just decreasing the quality of the compression without gaining too much when it comes to visual quality and its possible to make it even worse, especially since this file has already been through lossy compression.
Apple leans toward favoring quality over concerning themselves with file size. There original photo was 2.7MB. So just over that 2.5MB from above..
Anyway I said all that too say this.... Nothing useful can be gained from just comparing a photos files size. File size doesn't not directly reflect anything other statistic of the photo aside from tis file size....
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For your specific example of "sharing a trip" and assuming when you say "best way" you mean highest quality. Then I would probably just use an iCloud link send it too them however is convenient and let them figure it out.
If you never did it, just goto the share menu and click copy iCloud link and then paste it in a text, email, whatever. This link is too the original photo and it can transfer without any lossy compression.
I wouldn't totally throw out the idea of using a Shared Photo Album. The Shared Photo Albums aren't for photo and image processing and transferring, its a place that allows you, friends, family, coworkers, etc to share images with each other as a group.
So if you are trying to share trip photos with someone that doesn't care about JPG, HEIC, color space, etc its much easier for you to put the photos in an album on their phone vs expect them to goto iCloud. download HEIC files and then important them, etc....