A smaller vse video size please

Hello
as a musician, I like to make video clips with a 3-4 Mb audio file illustrated with some 5-10 photographs/pictures of about 4-5 Mb each photo.
In VSE, the ending .mp4 video yields a 60-80 Mb video file and I would like to reduce the size.
I tried to change the frame rate to one frame per second, and also tried to change image x-y resolution or percentage. I also tried different encodings.
so far, all changes do not reduce resulting video file size
my next try will be compressing photographs to under 1Mb each.
Can someone tell me how to compress/reduce ouput .mp4 video file ?
thnk you

Handbrake :