Robin, this is the original image.

It's almost 700k, which is enormous and will use up
your file space quickly while loading quite slowly
on some DSL machines and will take 3 minutes to load
on a dial-up modem. Probably saved at max-12.

Saving at max-10 or 11 or even high-9 is good enough
for 800x600 and barely different.

There's very little contrast seen via my monitor.