1974 $1 Sergeant Of The Light Horse "Missing Pink"

I have 2 1974 Australian $1 Sergeant of the Light Horse stamps. One of them is normal, the other has an imperfection. There is a distinct colour difference throughout the picture. My father worked on a post office counter and, as a boy, I can distinctly remember him bringing them home for me and calling the stamp "the missing pink". I am a novice in this area, can anyone provide me with any information about this stamp?

A pic would be helpful .

The ACSC indicates that the Note Printing Branch had difficulty printing the five colours required for this stamp. This caused a wide range of colour variation and led to the misconception that a "missing pink" variety exists. Normal stamps can range from yellowish to pinkish tones.

elitarpa.... Hi, BTW did you look at centre forehead above the nose, Dad may have collected the 'bullet hole' flaw.

Will need to see the image before any identification and comment can be made.

More accurately "missing magenta"
"slight mal-registration causes tonal differences"
Sc#573 1973.

Rod, is that the correct stamp or the one with the "missing" color ?

Peter

Hi Peter,
apologies, should have indicated.
My image is the normal stamp.
I was not aware, until this thread, there was a variety.
You may see some mis-registration on my stamp, near the elbow,
but has not affected the colour in any way.

Colours used:
Yellow / Magenta / Blue (Cyan) / Charcoal / Black.
varieties: PVA Blue tint gum
Black colour omitted, "cut throat" flaw.

Source: ACSC Catalogue number #3986 Circa 1989

Sorry. I should have included a photo with my first post - rookie error.