Mexico 1950 definitives - Architecture

[Rein]

The 1p (el Atlante de Tula) printed on the WIFAG has (at least) 2 (two) DIES!!


Die I:

[Rein]

Die II:

[jorgesurcl]

Hi Rein!

Differences between the left upper corners...also have to do with these 2 dies?

Die-I

die1mex.jpg

Die-II

die2mex.jpg

Saludos!

[Rein]

Jorge,

maybe, but in these stamps you have how does the side I showed look like???

saludos, Rein

[jorgesurcl]

Rein

The images that I showed are taken from the stamps you posted previously (your stamps)
Only I cut them and adapted to reduce the size, but the stamps are the same

Saludos

[Rein]

Rein

The images that I showed are taken from the stamps you posted previously (your stamps)
Only I cut them and adapted to reduce the size, but the stamps are the same

Saludos

Jorge,

Great!

There is a third die - or rather a defective way of moletting - that causes both the left hand side AND the right hand site to be hardly visible!

This cannot be a matter of wear! The moletting / rocking was done horizontally matching the circumference of the WIFAG cylinder, but the pressure was only placed upon the centre part of the design!

I will post this later today!

saludos, Rein

[Rein]

As said above - a very defective way of rocking form left to right or from right to left WITHOUT enough pressure all the way so only the middle part gets done properly!

[Rein]

[filatemusico]

Rein I found this damaged pair of stamps...

[Rein]

José,

moletting with two different dies????

The TIEV is very progressive and advanced .....

saludos, Rein

P.S.

any explanation for the "closed screen" photogravure?

[filatemusico]

José,

moletting with two different dies????

The TIEV is very progressive and advanced .....

saludos, Rein

P.S.

any explanation for the "closed screen" photogravure?

Rein, I have a theory but I 'm not sure.
When dots with size variation are used in photogravure, the dots as soon they are growing they get touch the another dots and then it look like a wire.
If you review the commemorative stamps of México very carefully, you are going to see that many stamps have dots with deep and size variation.

[Rein]

José,

the constant size of the dots was an effect of the glass screens used; in order to have a variable sized dot they needed to use an autotypical "screen" which was done in a completely different way.... and used in typography and offset-litho! The black "screen" you showed is such autotypical one!





saludos, Rein

[Rein]

Two glass plates - each having thousands of parallel lines - are fixed upon each other after turning one 90 degrees! In such way they used to get - an invention by George Meisenbach in 1881 - a cross-screen under 45 degrees.

In traditonally photogravure the glass plates were "touching" the plate/film which should receive the images, the dots even equally large as to surface; what Meisenbach did in order to reach an autypical screen on the plate was to keep a distance between the glass plates and the plate/film so by a diaphragma effect depending on the intensity of the light the dot would be smaller or larger.

[filatemusico]

About this souvenir sheet, catalogue Scott (896a) say that this is photogravure, which is not, because this do not have variation in tone, it is offset and it have the normal screen for offset.

[filatemusico]

Traditional photogravure have the same size dots, if a line for example is little bigger than a dot a part of other dot is added and if it is smaller, it only use a part of a dot but there are some stamps from Mexico that seem to have dots with variation in size. Please see the air coated papers 5 and 10 pesos in 1950-1975 series.