The first copies of the new Machin definitives with Security Features are now to hand, and I've had some fun scanning them to try to reveal the security features. The 'supermarket-style' slits are not of course a problem: each stamp has 4 cuts, sort of semi-circular. These are obvious to the naked eye and can be seen more clearly on the enlargements of these images.
The 'ROYAL MAIL' overprint is in a semi-visible layer, more obvious as the stamp is slanted against the light - as with phosphor bands. The semi-visible layer is an 'all-over' print, with the words ROYAL MAIL 'reversed out' ofthe part which is over the dark background (ie negative). But on the Queen's head, the words are smaller, and are 'positive', ie there is an area over the head which has a clear background, with the words printed in it.
The £1 stamp is shown above, heavily overexposed and the text can be seen on the phosphor band area. The Large 2nd class stamp is shown below: the first scan is 'straight' - no adjustments. The two enhanced images show more clearly the background and head text respectively.
Click on any image for a large version in a new window - for the benefit of anybody who is still unsure, there is NO green stamp. Images II & III have been digitally adapted to show the Security overprint!
Printing dates seen
1st class - 03/12/08
2nd class - 04/12/08
50p & £1 - 08/12/08
1st Large - 09/12/08
2nd Large - 10/12/08