Icloud photo storage compression
I have pictures taken last year with iphone6,. Stored on icloud photo library they have 300k size (small) every way I've tried to view them (eg using my pc, ipad etc ). A new test picture taken shows up as 3 meg, the size i expected. I want to get to the full sized files of old pictures on icloud for printing. How do I do this? What is causing the old pictures to be small? Apples documentation says it is storing the pictures on icloud at full size.
thanks for any input
iPhone 6, iOS 10.3.2