You have the beginnings of a nice collection,
it may be a camera problem, but there seems to be
toning around the perforations, that could be a problem.
My advice would be to get an early Stanley Gibbons "America Asia and Africa"
catalogue, you should be able to get one off
ebay for around $5
(circa 1965)
In that will offer you the stamps designer, printer and a little about the stamp
I particularly like the 40c stamp with the snake on it.