Maybe where you live it's easy to operate a 'just in time' buying strategy, but over where @Barking Mat is [and up here for that matter] opportunities are likely to be thin on the ground, so you sometimes have no option but to dive in when a chance comes along.
Welcome aboard, Fraser :waving:. A good place this with plenty of help and advice available, as @Mr Roo has demonstrated above. Quite a few Members in your neck of the woods, I'll let them introduce themselves. :thumbup:
I transfer the photos to the desktop, that way I can use Photoshop to change the image size to make the file more 'user friendly' and faster to upload - I can also correct the levels if necessary, to fix high contrast images.