Compression of picture or print is done with LOSSY COMPRESSION. Given your requirements you have no choice but to stick with your current setup.
If you ever relax your specifications you can try IRFANVIEW and use that to compress the images to some dozen other formats. This is not an offer to teach how to use IRFANVIEW or discuss the merits of 20 compression formats. All that has been discussed before so we always leverage what we can find on the web.
You're right. Can't be done without loss.
I am trying to export projects from Print Shop 2 to print on to A3 photo paper.
The company i use to print tells me my files are way too big, but i can;t figure out how to reduce the size without compromising the quality.
I am printing these as JPEGS 1200 DPI , they end up being around 150 MEG each.
Can anyone shed some light on this for me?