Austria, Franz Joseph 1876, Multiple Perforations - Why?

According to StampWorld, these stamps had various perforations.
Why? Were they printed in various post offices instead of centralized printing?
If so, I would have expected to find varieties in the image as well, for using different plates, like the bowknot in the 1859 issues.

A situation that was happening in more countries.

Stamp series from that era were in use for a long period of time. Many things could happen.

The perforation machine could be broken or not work properly, so they used another machine which happens to have a different setup.

The postal services asked for a different perforation to see if it made seperating stamps easier.

Demand made the use of more than 1 perforation machine neccesary.

Austria was a big country back then, which produced a lot of stamps for Austria itself and various areas of its empire, a mixup is easily possible.

Or it was simple lazyness and/or no one cared.(it happened)

Just a few reasons. There are more. Other members will follow up i'm sure.

Kind regards, Johan.

I don't have a catalogue to hand, but, from memory, some Austrian stamps from this period received unusual perforations by favour for well-placed stamp collectors.

Johan, all these are logical options, but which of them is/are the actual reason/s?
As for "A situation that was happening in more countries", the first country I would look at is Hungary, being part of the Austro-Hungarian empire, but I couldn't find a similar situation there.
Geoff, if collectors conspired to have artificially a variety of perforations, they would have wanted to have those changes acknowledged and add to the value, but in most catalogs, that assign a separate number to every hiccup and smear in a stamp, they bundle all the perf differences under one cat number, at least so I saw in Scott. How come?

If you look at an old Gibbons Europe, or recent/current Austria catalogue, you'll find that the different perforations are given different numbers and values. I'm not sure if this applies to your stamps, as I don't have a catalogue handy.

Scott catalogs are general ones for the whole world. Their editorial position is to give general information about those stamps that they deem legitimate. They do not try to give detailed information on all stamps. This is true of all catalogs. Someone has to decide what is going in and what can be left out. To find more details, one needs to look at country specific or specialist catalogs.

For the 1874-1880 issues my Scott catalog shows 4 main perf varieties
9 1/2 (the most common)
9
10 1/2
12
13

I found an article online that mostly addresses the fine print vs. coarse print but briefly mentions the perfs, saying that the different varieties were due to demand. But demand from whom? Collectors? People throughout the empire, which stretched from Poland and Ukraine to Croatia and northern Italy?

http://bigblue1840-1940.blogspot.co...hiskers.html

For those new readers here ,to understand which stamps are being discussed here ,I just put up my page on this issue . It is listed on the 5TH page of the Piece de resistance chapter .