That's sorted it thanks guys.
Files were just over 2MG.
Those phone cameras just get better and better eh?
The resolution of modern phone camera's and certainly of any decent digital camera is very high (let's say 6000 by 4000 pixels). Even with JPEG compression this leads to files of several Mb in size.
Our computer screens these days usually have a resolution of about 1980 by 1080 pixels. Even the newest 4K standard (still a bit uncommon in real life) only has 4096 x 2160 pixels, far less than what digital camera's produce.
Comparing those two shows that uploading full size pictures does not seem to make much sense. Even when viewing the pictures full screen will never deliver the full quality of the picture.
However, it is spoiling a lot of resources in bandwidth to upload the pictures, to store these on the kitmaker server, in bandwidth to download these again for each individual page view, and on the computer of the viewer that has to convert the large file into the local screen resolution. Basically, it slows down the site.
Hence, I use a simple tool (microsoft paint) to resize the pictures to something more appropriate for screen viewing such as a picture width of 1200 points. The 2+ MB a picture then becomes 400KB a picture or less.
An automated tool in the gallery doing just that(while storing also the original picture as backup and to regenerate pictures once the screen resolutions improve) would be better of course.
It would save the users some boring manual work and by reducing the size of all already uploaded full size pictures, would likely have a positive influence on the bandwidth and running costs of the site.